View Full Version : New arrival - Shuguang I-series integrated mini tube amp - everyone can afford them


GrantFidelity
02-05-2011, 06:20 PM
If the Shuguang 845T super monoblocks are too big for your house, too big for your wallet and too heavy for your back, these mini tube amps will fit all :)

Newly released to North America by Grant Fidelity, sub-$800, free shipping to all in North America (surcharge applies to Hawaii and Alaska).

Shuguang I-12 EL84 tube amp w/ headphone output and MP3 input

http://grantfidelity.com/site/files/I-12stockpicture.jpg

http://grantfidelity.com/site/files/I12coveroff.jpg

http://grantfidelity.com/site/files/I12rearview.jpg

http://grantfidelity.com/site/files/I12%20inside%20picture.jpg

Details link here: http://grantfidelity.com/site/shuguang_I12_integrated_tube_amp_headphone_amp

Shuguang I-25 EL34 integrated tube amp w/ MP3 input, loaded with Treasure tubes

http://grantfidelity.com/site/files/I-25%20front%20view.jpg

http://grantfidelity.com/site/files/I-25topview.jpg

http://grantfidelity.com/site/files/i25topview.jpg

http://grantfidelity.com/site/files/i25detail3.jpg

http://grantfidelity.com/site/files/i25inside.jpg

Details link here: http://grantfidelity.com/site/shuguang_I25_tube_amp

Sound Dragon
02-06-2011, 01:18 PM
I will await the official Ian Grant review....LOL. I looks really good to me and I am sooooo tempted to go this route. Just unsure if this amp will fit the bill for what I am looking for. I also however wonder if it is I-pod compatible using the I-pod's USB connection? Also would it pair well with the Dac 09 as a way of getting more inputs. For that matter will it work well with a P 307? speakers would most likely be either Klipsch Heresy or fortes.
Awaiting your impressions since I cant do a home demo from Georgia.

iGrant
02-06-2011, 01:35 PM
I've only got about 2 hours on the EL84 (I-12) after about 20 minutes I heard it open up. I am quite surprised by the sound and power already, I can fill my (19w x27 x8) room to loud rock level with my tiny 84DB GF LS3/5A speakers, I have heard enough new tubes amp to now that I am at best only hearing about 80% of what this amp can do after around 100 hours, then there is the Pavanes to roll in which I am sure will take it to a whole new level.

I guess my most relevant statement on them was I still had a smile on my face after almost crying watching the watching the Pavane 845-T monoblocks go out the doors, not of course the same, but these little amps are great sounding.

I had maybe 50 hours on the I-25 (EL34) amp before Rachel sold it, it too was a wonderful sounding amp, that meatier midrange EL34 sound, I'd lean towards the I-12 for your Klipsch's if you don't need lots of power.

Oh a friend brought over his Scott 22 EL84 (I think, it is the sought after one) which is in perfect condition with expesive tubes, it of course sounds great being 50 years old, but I think the Shuguang will be better after a few hundred hours.

Cheers,
ian

Pen Name
02-21-2011, 08:59 AM
I just got one of these, and will try to post some impressions soon. I am still breaking it in, and also braking in a pair of GF LS3/5As. If memory serves, the least efficient Klipsch is 91Db efficient, so at least 4 times as loud as the LS3/5As. Based on that, the I-12 should be loud enough to be uncomfortable in a medium-size toom.

Pen Name
02-26-2011, 02:26 AM
I now have about 25 hours on the tubes, that would make it about 65 hours on the rest of the amp. Using an old CPD as a transport through the TubeDAC-09 works nicely with the I-12. 89Db Definitive Technology oldies make Dark Side of the Moon sound very loud at 75% power in my 14x14X9 carpeted BR. No clipping or distortion noted. Pink Floyd never sounded better to my ears.
At this level of burn in the I-12 sounds better to me than the I-25 with about 22 hours on the whole thing. Frequency range is more extended than the I-25, more dynamic as well at this point.

eclein
03-29-2011, 06:53 PM
So which one sounds best to you Pen Name?? I'm going to jump on one soon, don't think about the Watts I already worked that out...

Pen Name
03-30-2011, 11:46 PM
So which one sounds best to you Pen Name?? I'm going to jump on one soon, don't think about the Watts I already worked that out...

I am afraid I only have a cop-out answer: it depends... on my mood, on the album, on the speakers I have connected for a given CD. Both amps are very musical, great soundstage, imaging, air, dynamics.
These are my first tube amps, so I can only compare them to solid state and each other. If I had to describe the sound:
The I-12 sounds like the general descriptions of EL84 tubes, and the I-25 sounds like the general descriptions of EL34 sound.
If I may make an analogy: The EL34 sounds more like German baroque, e.g. Pachelbel. The EL84 reminds me of Italian baroque, e.g. Vivaldi. The I-25 is more restrained and controlled, the I-12 more exuberant but perhaps less profound.
If I had to pick only one I would pick the I-12 - even though the I-25 comes with $280 of black bottle EL34s, the I-12 can be upgraded to black bottle EL84s for $160. I have not done that yet, so I think the I-12 can sound better than it already does. EL84s are a lot cheaper to replace than EL34s.
In addition, the I-12 has a headphone jack driven by the tubes, and it sounds sweet. The I-25 does not have that. So in my view the I-12 is a better value at $575 than the I-25 at $785, even though the I-25 comes with $240 worth of output tubes, and the I-12 with about $40 of output tubes.
To my ears the difference in volume produced by the two amps is minimal, as you would expect with a mere doubling in output watts. The I-25 seems to have marginally better bass control, but lacks the sparkling highs of the I-12.
I am quite addicted to each amp.
I hope this helps.

Pen Name
04-01-2011, 12:29 AM
Tonight I listened to Vivaldi string concertoes on the I-25, and in addition to the fabulous soundstage, imaging and air, there was an astounding amount of resolution and nuance, and I thought: it would be stupid to buy anything other than the I-25.
BTW - it seems to take about an hour of warm-up before these amps sound their best, after break-in.
I find that my system with LS3/5As sounds better than the LS3/5As sounded with the new Shuguang 300B amp in the GF showroom. That has probably more to do with the acoustics in my room and the quietness of living out of town compared to the noise in the GF showroom, and less with the amp - but I think it is also an indicator of how good these amps are.

wwb6001
04-03-2011, 12:45 AM
Hi Pen Name!
It seemed you were kind of preferring the I-12 in a previous post. Have any new impressions to share? I am getting ready to order one of these and reviews are proving hard to come by because they are so new! I don't have the most efficent speakers in the world so was leaning towards the I-25. My ears are so burned out on the shrill from SS and digital stuff the "sparkle" you described with the I-12 almost scares me. ;) I do love a strong mid range and good bass, so again, leaning towards the I-25. Just want to make the right decision. :) Thanks!

Pen Name
04-03-2011, 04:06 AM
Hi Pen Name!
It seemed you were kind of preferring the I-12 in a previous post. Have any new impressions to share? I am getting ready to order one of these and reviews are proving hard to come by because they are so new! I don't have the most efficent speakers in the world so was leaning towards the I-25. My ears are so burned out on the shrill from SS and digital stuff the "sparkle" you described with the I-12 almost scares me. ;) I do love a strong mid range and good bass, so again, leaning towards the I-25. Just want to make the right decision. :) Thanks!

My initial impressions were based on the sound before burn in. The black bottles in the I-25 have become very sweet.
Based on your descriptions of your preferences, you may prefer the I-25.
The treble on the I-12 is never harsh or shrill. It is brilliant and grain-free.
The I-12 may sound even more refined with the Psvane tubes.
If you do not yet have a GF TubeDAC-09: it is a wonderful little device that will allow you to plug in 5 sources, and a choice of Tube or SS out to the single RCA input if the I-12 and I-25.
I was in a similar position as you were with these amps - so I decided to get both, for less $$ than 1 amp anywhere else. Each of them is a joy to listen to, and I can hardly peel myself away from them.

Pen Name
04-10-2011, 03:30 PM
Since no reviews of these amps have been posted at the website, I have tried to write something more complete that may assist people contemplating one of these units to be a bit more informed in their decisions.
Here are a bunch of caveats:
1. I am not an audiophile – but I have read enough crap on the internet to be able to sound like one. So don’t trust my judgement or my words.:bs:
2. My room, my associated equipment, my ears. Not much hi-end here. Room is 14x14x9 carpeted BR with a bunch of junk in it. Current equipment: Sources: Sony CPD CE245 and Pioneer HDD/DVD recorderDVR-460H (both used as transport only); Motorola Satellite receiver routed through Pioneer. DAC: GF TubeDAC-09 (Straight DAC); GF TubeDAC-09 (preamp); Amplifiers: Shuguang I-12; Shuguang I-25; Harman Kardon 3490 (used as power amp). Speakers: Definitive Technology DR-7 floorstanders; GF LS3/5A. Interconnects: various generic RCA (and 1 GF brand), generic USB, generic optical and digital audio. Speaker wire: 1 GF, 1 generic ‘Mammoth super flex oxygen free copper’. Beauty eh!? Cut to about 7’ long. Power cords: GF power cords for the Schuguangs and the DAC, original cords for everything else. Everything plugged into a GF power conditioner. My ears: pretty ancient, can’t hear treble like I used to...
3. Preferences: The way I like my music may not be the way you like yours. How do you like your steak prepared?
4. And to add to the complexity: I am not a skilled listener; I am in the beginning phases of training my ears and my brain. This limits what I am able to hear, and flaws that may be obvious to others may not be noticed by me.
I have been unable to discern differences in sound between GF interconnects and the cheap generics. The GFs look much better, though.
I have been unable to discern audible differences between the butch GF power cord and the original power cord supplied with the DAC. I have not tried swapping GF and stock power cords on the Amps.
I have been unable to discern audible differences between the GF and Mammoth speaker cables.
HK 3490 receiver vs. Shuguang Tube amps: the HK benefitted significantly from using a TubeDAC-09 as preamp, bypassing the built-in HK preamp. A veil was lifted. From what I read on the ‘net, this should be audio nirvana: the sweetness of a tube preamp with the low distortion, dynamics, power and bass control of 120 WPC SS power. No nirvana noted: the HK is able to play loud with power to spare, but there is a lack of refinement in comparison to the tube amps. The HK adds artefacts to the sound. The HK lacks refinement and precision. The HK makes an absolute mess of classical and baroque music. On the plus side: the HK runs cool and quiet. My younger son prefers the HK to the tube amps, because the HK is louder.
I-12 vs. I-25. The amps share their looks, the single RCA inputs, and the built-in MP3 player that plays at such a low level that it is virtually useless for serious listening. The sound quality of the MP3 is not bad, the quantity is. The smaller I-12 has a headphone jack that the I-25 does not have. I have swapped speakers between the two amps, and the amps sound different from each other with each speaker. The amps are neatly packed in foam in a double cardboard box. The tubes are inserted into the amp, and held in place neatly by the foam packaging.
Value: The I-12 has 12 WCP of EL84 power. The 4 EL84s are generic Shuguang tubes. I have not upgraded the tubes, and there are many possible upgrades, including the Psvanes. The I-25 has 25 WPC through 4 EL34 Shuguang black bottle Treasure Tubes. My estimated replacement costs for the 4 EL84s is about $40, the 4 EL34 about $280. For the $240 difference you could replace the I-12’s EL84s and two 12AX7s and have an amp that should sound better than stock and keep the spare tubes. The only problem is that once you add $240 to the price of the I-12 it is actually more expensive than the I-25 for half the WPC.
Build quality: identical for the two amps. Both are heavy, solid, thick aluminum face plate. Both are smaller than the HK, but weigh 2 – 3 times as much. These amps are more expensively built than your Denons, HKs, etc. All parts to fit together well. The I-25 is only a little bigger than the I-12, but considerably heavier. Switches, volume control, binding posts all have a high quality feel to them. The only problem I have encountered with the amps is with the headphone jack of the I-12. (I should mention that Ian Grant is determined to resolve this issue!) Sometimes it mutes the speaker outputs, and sometime it does not. In addition, the channels on the headphone jack are reversed. None of this is a big deal to me, because I use the RCA tube outputs on a TubeDAC-09 preamp for cans.
Sound quality: first the bad – the headphone outputs in the I-12 are quite noisy even when it works as well as it can. There is a noticeable amount of hum that is not increased by turning up the volume on the amp. I can adequately deal with the hum in the headphone output by turning the volume of the amp to `noon` and lowering the volume on my cans. But if I turn up the volume on the amp beyond `noon` other noises start to appear – not sure how to describe these noises... Variable frequency wobbling hiss?
Sound quality: The good: the sound through the speakers. Both amps are very well-behaved and sort out the input signals nicely. Both amps are very quiet, just a faint hum with full output is noticeable when you are very close to the speakers. So no worries about sounds that I should not be hearing – there are none. This is important to me. I live out of town, and my listening environment is very quiet. And anything that intrudes as noise on my music is a real annoyance to me. Both amps present a bigger 3D soundstage though the tube output than the SS output of the TubeDAC-09. I have the inner edges of the speakers at about 5` from each other, my ears are about 6` from the tweeters (and at ear level). The soundstage presentation depends a lot on the recording of a particular disc. At times the soundstage has been too wide for my little brain to comprehend, and I have needed to move away from the speakers to make the music more manageable for me to comprehend. There was never a gap in the centre, the music has just been too spread out for my brain to comfortably put it together – and there are times when I just do not want to work that hard. (This is challenge only with classical and baroque. Modern music may have detail, but to me that detail is more ornamental than meaningful, so it does not require much effort to integrate.) Anyway – any lack in soundstage width has nothing to do with these amps. Soundstage height is less huge. Depth is impressive. All of this is probably also affected by my listening room. Imaging is absolutely stable with both amps. With a decent quality recording each instrument and voice is in its own place in a 3D sound image, and stays there – unless the performer moves (e.g. Opera), or the recording engineer plays tricks (e.g. classic rock studio recordings.) Anyway, I used to listen to classical and baroque music almost exclusively through cans because the sound coming from various Yamaha and HK receivers through the DefTech speakers was so confused and muddled. Now I prefer listening through the speakers because of superior soundstage and dynamics. I had expected the tube amps to sound sweet with acoustic instruments and voice, and they do. An additional pleasant surprise is who they smooth out electronic instruments. In my set-up I can hear a lot more detail with a bit more volume with each amp.
How the amps differ: This is where things get difficult for me. The I-12 sounds ‘lighter’ and leaner to me than the I-25, but the I-25 is no less agile. Initially the I-12 seemed to have more sparkling treble than the I-25, and also more base, but this changed as the I-25’s tubes burned in more. The I-25 changed its character much more than the I-12 during burn in. I am not sure that the amps are completely done burning in, but I think their characters are now fairly clear: The I-25 is everything that the I-12 is and more: more and better controlled bass, more mids, and more treble. More detail, more ‘density’, more everything. That would be my A/B comparison. In terms of extended listening, I find the I-12 to be an absolute joy. It works great with the TubeDAC-09 and both sets of speakers in producing a musical and organized soundscape. Yesterday I enjoyed every minute of a 14 hour listening session with it. The I-25`s sound changed a lot since it first arrived. At first there was not much sound at all, and what was there did not really sound like music. It took about 20 hours for bass to introduce itself, and welcome though it was, it was uncontrolled at first. It was a lot of fun to hear the amp get better and better - probably mostly the tubes that kept improving.
Bach Brandenburg concerto 6, 3rd movement test: I-12: lots of viola notes in left channel, backed up by orchestra. I-25: 2 distinct violas playing their lines in left channel, backed up by orchestra. Variables: I-12 was hooked up with GF interconnects to GF speakers; I-25 hooked up to DefTechs through cheap generic RCAs. I-25 wins this test!
Final notes: Grant Fidelity ships their products free of additional charge in North America, I believe. Ian and Rachel kindly arranged to open up their showroom on a Sunday when I had a chance to be in Calgary on a Sunday, and meeting them allowed me to have confidence in them and their company. Over the last year I have made several purchases from them, and the orders have always shipped immediately, and been packaged very well. Ian and Rachel are committed to customer support. In dealing with Ian and Rachel I feel treated like a person rather than a credit card number, and that is very reassuring.

jimfet
04-10-2011, 10:07 PM
I bet that sounds nice. Sure looks nice. I do wish there was a bigger selection of power amps though. Tube integrated amps seem to be more popular.

GrantFidelity
04-11-2011, 07:29 PM
the built-in MP3 player that plays at such a low level that it is virtually useless for serious listening. The sound quality of the MP3 is not bad, the quantity is.
 
Try press and hold 'next track' button beside the MP3 port, it should increase the volume - then adjust the amp's main volume control to get to where you want... this may help to get the MP3 playback volume right.

Thank you so much for taking time to write your feedback - it is greatly appreciated. Your comments about I-25 is everything of I-12 but more confirm the magic of the Treasure tubes. You may have to change your regular EL84 to Psvane EL84-T to keep up with the I-25. I somewhat feel the headphone noise is related to the generic tubes as well. These amp are of great structure in stock form - some tube upgrade will bring more of the inner beauty out of them.

Did you see our new Demonstrator map on Google map? (http://shop.grantfidelity.com/Audition-and-Demonstration.html) If you are interested in claiming your spot on the map, just send me an email I will have you set up :) I am behind on paperwork so any past customers see this thread and would like to join the map, email me through our website. It will take a while for me to send out all invitations one by one.

Rachel

Pen Name
04-12-2011, 09:04 AM
 
Try press and hold 'next track' button beside the MP3 port, it should increase the volume - then adjust the amp's main volume control to get to where you want... this may help to get the MP3 playback volume right.

Thank you so much for taking time to write your feedback - it is greatly appreciated. Your comments about I-25 is everything of I-12 but more confirm the magic of the Treasure tubes. You may have to change your regular EL84 to Psvane EL84-T to keep up with the I-25. I somewhat feel the headphone noise is related to the generic tubes as well. These amp are of great structure in stock form - some tube upgrade will bring more of the inner beauty out of them.

Did you see our new Demonstrator map on Google map? (http://shop.grantfidelity.com/Audition-and-Demonstration.html) If you are interested in claiming your spot on the map, just send me an email I will have you set up :) I am behind on paperwork so any past customers see this thread and would like to join the map, email me through our website. It will take a while for me to send out all invitations one by one.

Thanks Ian, I was indeed able to increase the MP3 output. Problem solved!
I also suspect the tubes as being the source of the hiss in the headphone output. One of these days I may upgrade to the Psvane EL84s, and then :music:

iGrant
04-12-2011, 09:29 AM
Interesting review. I think you are having way too much fun by going the two amps instead of the S300MK route :), which you still will have to hear again someday. I listened to the I-12 for about an hour with the stock tubes and quite enjoyed, Put in the Pavanes and was a dramatic improvement. I did all 8 tubes with the Pavanes. I'd say you are hearing about 60% of the I-12 and until you do the pre and driver Pavanes in the I-25 you are hearing about 80%.

Are you adjusting your GF LS3/5As with amp rolls?, did you notice in our showroom the clear plastic markers on the floor, they represent where certain speakers sound their best (to my ears) as you roll in different amps, I suggest you try different speaker positioning, if the soundstage is getting too wide for you, toe in a bit.

That was Rachel answering you. I didn't hear any hiss on your I-12 with Sennheizer HD 540s. Most have heard this story before, guess who Rachel sold my I-12 to :)

Cheers,
Ian

Pen Name
04-13-2011, 08:58 AM
Interesting review. I think you are having way too much fun by going the two amps instead of the S300MK route :), which you still will have to hear again someday. I listened to the I-12 for about an hour with the stock tubes and quite enjoyed, Put in the Pavanes and was a dramatic improvement. I did all 8 tubes with the Pavanes. I'd say you are hearing about 60% of the I-12 and until you do the pre and driver Pavanes in the I-25 you are hearing about 80%.

Are you adjusting your GF LS3/5As with amp rolls?, did you notice in our showroom the clear plastic markers on the floor, they represent where certain speakers sound their best (to my ears) as you roll in different amps, I suggest you try different speaker positioning, if the soundstage is getting too wide for you, toe in a bit.

That was Rachel answering you. I didn't hear any hiss on your I-12 with Sennheizer HD 540s. Most have heard this story before, guess who Rachel sold my I-12 to :)

Cheers,
Ian

Sorry Rachel, I should not post anything before I wake up... And thanks to both of you.
I've had the speakers pointing in pretty much every direction from anywhere in the room, experimented with playing pink noise while moving through the room, etc. Hard work, but somebody had to do it... Anyway, this is still a temporary set up, and there are only so many (one) places where I can leave speakers lying around in the bedroom. No fault of the speakers or system if the soundstage is wider then I can comfortably put together in my brain. It is a function of a lack of familiarity with the music and its presentation. By moving away from the speakers I can change my virtual listening position from Front Row Centre to mid hall. Nice.
I picked the 2 'lesser' amps over the 300 to create a learning opportunity for myself. There is only so much I can do in a showroom.... And I had scoured the 'net for years like a pirate and realized that the I-xx amps are great values. There is nothing close to this price with these specs unless you are willing to go the DIY route and provide your own chassis. The S300 MK is next, after the kids have completed post-secondary education and after the I-xx amps are upgraded fully with Psvane tubes. I may not live that long - but I don't feel I am missing much with these amps. They may be cheap, but they are well-built, cute, and really nice sounding. And at least nobody sells them on me while I am not looking!
Cheers, P.

volks
04-21-2011, 07:51 PM
My Shuguang I-25......i have over 150 hours on it now and it has really opened up and is playing very sweet with good bass control as well......i have KEF IQ 10's hooked up to it in my second system.
Like most tube amps it needed time to "Break In" to sound its best.....not only that,but my Kefs were brand new and also needed at least 100 hours to break in as well....otherwise making an opinion the day i got the amp or the day after i got the amp is kinda pointless.
For an amp of this price the midrange is actually smooth and on CD's so far it has not colored the sound in any way.
I actually hooked it up to my Reference system with my KEF Reference 207'2s and the Grant Fidelity CD-1000 Impression II Tube CD Player .....i was surprised the little amp powered the KEF 207's so well.......i must say i am very pleased thus far :)......as always of course Ian and Rachel are top notch in every way! :thmbsp::banana:

Thanks Ian&Rachel.......keep up the great Customer Service!:music:

MP

Pen Name
05-27-2011, 03:47 PM
Added the Psvane 12AU7 and 12AX7 tubes. I don't believe they are quite broken in yet, but the I-25 alread sounds more refined - improvement on a high standard. A bit more air, more organised soundstage, some more depth and detail. A very addictive amp.

volks
06-05-2011, 12:12 PM
Pen Name how's the sound comming out of the Psvanes now?Must sound even better now ! :)

Pen Name
06-08-2011, 12:10 AM
Sorry volks, I really have not had an opportunity to do any listening lately - so no further breaking in. Once I have more time on the tubes, I'll let you know. As you know, the I-25 is pretty fabulous stock, and I did not hear dramatic differences on the new tubes. That said, I also suspect that my speakers have become the limiting factor in my sound system.

Pen Name
06-14-2011, 12:13 AM
I dug out the Harman Kardon 3490 and compared it to the I-25. The Harman Kardon had some distinct advantages:
1. It’s cheaper.
2. It has more power (120WPC@8Ohms vs. 25WPC) and plays loud effortlessly.
3. It gets less warm.
The HK produces a decently wide soundstage, but it is 2 dimensional. There is no depth to it. The I-25 does not really produce a soundstage. It produces music in a venue. It allows me to hear the dimensions of the hall/room/church in which the music was recorded – on good recordings. The various instruments are in their own space. This has permitted me to follow musical lines in counterpoint baroque and classical music with much greater ease, helping me understand the music better. I used to use headphones to get the detail from the recordings, now I use speakers in super near field (I can touch the speakers from my listening position) far away from any walls. On modern music I can only guess how the ambient effects were achieved – but on good recordings (I Robot, The Wall, Dark Side of the Moon) the effects are stunning.
Some thoughts on the sound of the I-25: I am not sure if it is accurate. It is beautiful, possibly more beautiful than a real concert. The HK sounds more rolled off than the I-25 in the treble range. That was unexpected, after all I had read about tubes. HK bass is drier than I-25, but I’ll take the bass of the I-25 on a double bass, cello, bassoon, any time over the HK. HK may have an edge on base guitar. Midrange is no contest. Attack and decay and everything in between are so much sweeter on the I-25.
Another difference is the ‘sound shape’ of the reproduced instrument. Acoustic instruments sound like spheres or orbs on the I-25, there is a volume to the instrument or group of instruments. The HK produces a stripe or at best a sheet of sound. The I-25 sounds alive and makes music, the HK makes sound. The I-25 also does not produce any grain that I can hear.
I think the speakers are now the greatest limiting factor in my sound system. I do not feel much need to upgrade from what I am hearing now. But there are a few ‘issues’: I hear more glare on massed voices (especially loud passages) through the speakers than through my headphones. I am not sure where the origin of this issue is – amps, speakers or my ears. I have upgraded my ears as much as possible... And there is some congestion on loud complex classical music. So I may just be forced to come up with more efficient speakers – could there be Zu in my Zukunft? But then again, why get efficient speakers first while there are some perfectly fine 845 monoblocks that come with free shipping...

guystp
06-14-2011, 09:44 PM
Hi Pen Name, if you ever get the opportunity to listen to Grant's RBS-1, I think you'd be impressed. I'm using the A-348 amp with Treasure tubes, and when I auditioned the RBS-1's, I was blown away. I wound up buying the MBS-1's but only because my room is simply too small for the RBS-1's. I've really enjoyed reading your review on the I-25. It very nice to read articles from actual users in the real world.

Pen Name
06-15-2011, 04:05 AM
Hi Pen Name, if you ever get the opportunity to listen to Grant's RBS-1, I think you'd be impressed. I'm using the A-348 amp with Treasure tubes, and when I auditioned the RBS-1's, I was blown away. I wound up buying the MBS-1's but only because my room is simply too small for the RBS-1's. I've really enjoyed reading your review on the I-25. It very nice to read articles from actual users in the real world.

Thanks for the feedback, nice to hear.
I did have a chance to hear the RSB-1. They certainly are a nice speaker - but I think I may be looking for something a little less neutral. I have come to the conclusions that I am not really looking for realism - I am looking for better than realism, just like the old kodachrome slides made colours more vibrant than in actual life, especially the reds. Some of the Focal speakers have that French romantic presentation, as opposed to the British reserve of my GF LS3/5A. But before I go there I want to listen to some crossover-less speakers, like the Zus or the Omegas. I also would like to hear some electrostatic panels/ribbons before making any commitment, although I fear that those kinds of speakers will not be a good match for a low-powered tube amp. Ian / Rachel: any comments on that?
BTW, had the privilege to hear some aboriginal music live yesterday. Four men singing and each beating one drum. There is no way that my little system comes anywhere near the macrodynamics of the drum. Also a couple of ladies singing and each beating a hand-held drum. My system would not be able to even reproduce those drums accurately. But it could come very close to the voices.
Cheers,
PN

Pen Name
08-03-2011, 01:26 AM
and then I had the opportunity to hear the RFS-1 floorstanders at the Grant Fidelity showroom - and they lacked the glare on choral works that I have heard on every other speaker. So I had to get them. I am happy to report that they work very well with the I-25, I think I really have some synergy going now. I believe they may be a bit easier to drive than the GS LS3/5S, and they have a more exciting presentation as well. Treble is clearer, bass is deeper, and the mid range is still all there. LS3/5As will beat the RFS-1s in depth of soundstage in my room. But I am still fiddling with the placement of the speakers.

iGrant
08-03-2011, 09:06 AM
With offset mirror imaged tweeters generally they are voiced to on the inside, especially studio monitors which all of the GF speakers need to be able to double duty as.

That is how I played the RFS-1 (Reference Floor-standing Speakers) for you on your visits. You should be able to get very close to the LS3/5A's sound-staging. I have a feeling you will experiment and do let us know if you like them with the tweeters outside.

It's the Morel Drivers that are providing you with the almost glare free performance and thanks for educating me on this one, seems this very important classical voice and opera fans.

Cheers,
Ian

Pen Name
08-05-2011, 12:48 AM
You are too modest Ian - you are the one who educated me. And you brought this speaker to my attention in response to my described tastes.
I will indeed continue to experiment with placement. A really cheap audio tweek! The bass response of the speakers relating to their distance from the front wall is enormous - I suspect at least in part to the rear transmission line output. These speakers can really energize the room. It is also nice to be able to 'add' some bass when turning down the volume by moving the speakers closer to the front wall.
I am still seeking for the perfect placement, and hope to have some more time to do so this weekend. One of my problems is that these speakers are so darn musical that I tend to listen to the music more than to the speakers - a good thing!
I think you are correct about these speakers being very compatible with classical music but they also to classic rock nicely.
Finally - in addition to voices, glare tends to be very noticeable on flutes and recorders - probably because of the way the tone is formed - splitting air.
Thanks again for your help and expertise!

Pen Name
08-09-2011, 12:39 PM
I tried listening to the speakers with the tweeters towards the outside for about8 hours straight. It sounded a little confused to me, despite my anticipation that time allignment would be improved. Eventually my ears / brain adjusted for much of the confusion, but putting them back in the original configuration was an immediate improvement in their music presentation.
My preference is to still listen in super nearfield but with more space than with the GF LS3/5A and Def Techs. Grills off - lots of detail, treble is more pronounced than on the LS3/5A, perhaps even more than in real life (but I love it!) but without any harshness. Lots of 'air'. I have the speakers about 5' away from the front wall. Lots of music.

iGrant
08-09-2011, 02:44 PM
I tried listening to the speakers with the tweeters towards the outside for about8 hours straight. It sounded a little confused to me, despite my anticipation that time allignment would be improved. Eventually my ears / brain adjusted for much of the confusion, but putting them back in the original configuration was an immediate improvement in their music presentation.
My preference is to still listen in super nearfield but with more space than with the GF LS3/5A and Def Techs. Grills off - lots of detail, treble is more pronounced than on the LS3/5A, perhaps even more than in real life (but I love it!) but without any harshness. Lots of 'air'. I have the speakers about 5' away from the front wall. Lots of music.

Still basically Equal Triangle ? as per this:

http://grantfidelity.com/wordpress/high-end-audio-tweaks/setup-your-existing-system-first/

If so you are likely getting quite close to the typical studio near-field monitoring setup, which is a good way to emulate what the engineer heard.

Cheers,
Ian

Pen Name
08-09-2011, 06:13 PM
Still basically Equal Triangle ? as per this:

http://grantfidelity.com/wordpress/high-end-audio-tweaks/setup-your-existing-system-first/

If so you are likely getting quite close to the typical studio near-field monitoring setup, which is a good way to emulate what the engineer heard.

Cheers,
Ian

An equal triangle of exactly 40". I measured, just for the heck of it...
I went by sound, making sure that the speakers were aimed just behind my ear at the shoulder, being in the exact centre between the speakers. My distance from the speakers was determined by how I liked the sound best, which turned out to be the same distance as the centre of the speakers from each other. I think I could expand the sides of the triangle a bit without feeling that I am missing much.

cheers, P

Pen Name
09-27-2011, 03:18 AM
The I-12 and accompanying TubeDAC-09 are reportedly the life at the party at the residence. My son hooked up a PS3, his iPod and his laptop. Apparently gunshots from PS3 games can be heard way down the hall, and this is a good thing. Tubes a proudly displayed on facebook. Anyway, Ian and Rachel, just wanted to let you know that indeed for a dorm the I-12 is plenty powerful, and that even in residence at least some people notice that there is a difference between an iPod dock and a stereo. I do miss the I-12 though, it is a sweet little amp.

Pen Name
09-27-2011, 03:26 AM
And a final update on the I-25. It is working beautifully with the RFS-1 prototypes. And that is the reason I have not posted much - I have been way too busy listening to music! Even though the I-25 is marketed as a "mini", it is totally capable of driving these relatively inefficient 85 dB 2nd order crossover two way floorstanders. Volume know is at 11 for classical, 2 o'clock for playing rock music loudly. I suspect that there is still a level of detail that I may be missing in the I-25 that a W-30 may be able to retrieve with the EL34 tubes, but I am finally no longer in a rush to upgrade.

volks
10-05-2011, 03:58 AM
And a final update on the I-25. It is working beautifully with the RFS-1 prototypes. And that is the reason I have not posted much - I have been way too busy listening to music! Even though the I-25 is marketed as a "mini", it is totally capable of driving these relatively inefficient 85 dB 2nd order crossover two way floorstanders. Volume know is at 11 for classical, 2 o'clock for playing rock music loudly. I suspect that there is still a level of detail that I may be missing in the I-25 that a W-30 may be able to retrieve with the EL34 tubes, but I am finally no longer in a rush to upgrade.


Pen Name I agree 100% with the I-25 being able to power big gun speakers...... Whenever I hook it up to my big Kef Ref 207'2s I am always amazed at the lvl of bass authority and midrange detail and remember I have just the stock tubes!!!!!.......I think it's time for myself to do a nice tube roll and see what this little amp is really capable of:)

Pen Name
10-05-2011, 04:45 PM
Mine sounds really nice with the black bottle EL34 and Pavane 12AX7 and 12AU7 tubes. But then it sounded really nice before I rolled in the Pavane tubes... I suppose I could roll in the old tubes and listen for any differences - but I find that the I-25 takes 2 hours before it sounds its best, and by that time my memory may have faded. Being noob to toob - I have read that the tubes may require 2 hours to fully warm up. I find that hard to believe - and I do not notice that the tubes really get any warmer after about 10- -20 minues. The output transformers seem to take 2 hours before they are as warm as they get. I wonder if that may be the difference? Any answers out there!?
Most important thing to me:I seem to have real synergy going with CD transport > TubeDAC-09 > I-25 using the GF power conditioner, GF power cables, GF interconnects and GF speaker wire. When I listen to music through this system I just feel happy (OK, not the first 20 minutes when things still sound a little out of whack). But after that I get a sense of real well-being, happiness, and the illusion that life really is great. All that without a hangover :)

etocynned
10-06-2011, 05:08 PM
im new to this forum, thanks for being here!

I have just acquired, after 15yrs waiting, a pair of B&W Dm302 stand mount loudspeakers.

They're high sensitivity, 92db measured, but tough in the midrange impedance wise. I intend to use them with a turntable and my laptop in a system in a small room.

Here's a link to the Stereophile review: http://www.stereophile.com/budgetcomponents/542/

I used to sell them and fell in love with them, got these at a garage sale for $50, BAM!

Is the I-12 a good match? I don't like to headbang, but i just really want to have a tube amp!

My system is an Hitachi Turntable, Radio Shack Phono Pre, and the speakers. all dollar store interconnects. I was using a Samsung DVD home theater amp to drive them before so anythings a step up.

Ill get new interconnects as i go along.

If i can swing this purchase and it works well, ill definitely be a demonstrator! I'm in Chilliwack,BC

iGrant
10-06-2011, 08:23 PM
That's quite the impedance chart !, all over the map, I'm surprised they didn't label them 6 ohm. Fortunately you have the 4 ohm taps on the I-12 and decent transformer weight if the 8 ohm taps don't do it, and probably will be just fine on the 8ohm taps. 12 tube watts should be plenty and the I-12 is a fun tube amp, it plays way above it's rated power as the harmonic distortion of the EL-84 is quite pleasing for headroom, I think you will get lots of enjoyment from the combo.

Cheers,
Ian

etocynned
10-07-2011, 12:43 AM
Cooooool! I'm so gonna get one!

Pen Name
10-07-2011, 02:50 AM
I gave my son my I-12 as a grad gift along with a TubeDAC-09 and a pair of 90dB polk M60. To my ears the speakers are the weak part of his system, which he now has in his dorm room. Here are a couple of his comments:

"My roommate tells me you can FEEL the bass from my system in the elevator... Now that is sick. :D"
"One of the best things about having guests over is showing off the sound system!"

It sounds clear, cheerful, musical, and well beyond its price. It does need to burn in for 100 hrs or more before it settles into what it can do. All of this with the stock tubes. I still miss this amp. Still thinking about getting another one! :)

Pen Name
10-07-2011, 03:03 AM
Pen Name I agree 100% with the I-25 being able to power big gun speakers...... Whenever I hook it up to my big Kef Ref 207'2s I am always amazed at the lvl of bass authority and midrange detail and remember I have just the stock tubes!!!!!.......I think it's time for myself to do a nice tube roll and see what this little amp is really capable of:)

volks, those are some really big ass speakers, costing real $$. Nice! I know how good the I-25 is - but don't you get the sense that your speakers could go a level higher with a 300B or RITA?:scratch2:
The lack of money is the root of all evil...:drool:
I would love to find out if an amp upgrade would enhance my sense of happiness listening to my current system, or mess it up...

volks
10-07-2011, 03:59 AM
volks, those are some really big ass speakers, costing real $$. Nice! I know how good the I-25 is - but don't you get the sense that your speakers could go a level higher with a 300B or RITA?:scratch2:
The lack of money is the root of all evil...:drool:
I would love to find out if an amp upgrade would enhance my sense of happiness listening to my current system, or mess it up...



I agree Pen Name and thats why i have the big Kefs hooked up to my Mcintosh MC 601 Mono Blocs..........but for fun i do love to hook the I-25 up to them from time to time...........i have the I-25 hooked up to my bedroom system Kef IQ10's.:)

Pen Name
10-09-2011, 12:23 AM
I agree Pen Name and thats why i have the big Kefs hooked up to my Mcintosh MC 601 Mono Blocs..........but for fun i do love to hook the I-25 up to them from time to time...........i have the I-25 hooked up to my bedroom system Kef IQ10's.:)

:jawdrop:
Well, volks, I am afraid that you will just have to make do with the 601s until you can save up for something better! Nice system!

volks
10-10-2011, 12:48 AM
:jawdrop:
Well, volks, I am afraid that you will just have to make do with the 601s until you can save up for something better! Nice system!



Thank You Pen Name :)

Pen Name
08-10-2012, 06:52 PM
I rolled the top of the line Psvane 6ca7 tubes into the I-25 amp yesterday. After about 18 months of pretty heavy use I had to up the volume from 11 to noon on the original Shuguang treasure tubes, so I figured it was time to replace them. Even without burn in the Psvane tubes are superior. More tone and texture, detail, better soundstage, more deep base. Volume is back down to 11. This little amp is well worth $360 in power tubes, the difference is not subtle. I do not remember the Shuguang treasure tubes ever sounding this good.

Pen Name
08-10-2012, 06:54 PM
Oh, one caveat: the Psvanes are taller than the Shuguang treasure tubes, and I had to modify the tube cage so it would not hit the top of the tubes. A 2 minute job with some electrical tape :)

etocynned
09-12-2012, 12:08 AM
Sadly my i25 now sits in the pawn with my dm302's. Anyone near Chilliwack can buy it, the tag is at $450. They have the Dm302's at 200.

Im definitly getting another GF sourced amp, considering the w30 or a SET and DAC11.

ill never get over the glow, the beautiful glow!

I must say the service from Ian and Rachel, the care the display, even from hundereds of km away, WOW!

A customer for life!

Sword86
09-18-2012, 03:59 PM
What will it cost you to get them out of pawn? Hate to see someone lose their 'stuff'.
Let me know......maybe I can help you out. I'm in downtown Vancouver.

86

etocynned
09-18-2012, 04:09 PM
They want450 for the amp and 200 for the speakers.

Sword86
09-18-2012, 04:21 PM
Sent you a PM.

86

BluesDaddy
02-16-2013, 06:10 PM
Can anyone speak to whether the noisy headphone jack for the Shuguang I-12 referenced by Pen Name in post 11 can definitively be resolved by using different tubes? I'm interested in this amp, but headphone listening is very important to me and I don't want to invest in even a modestly priced amp that doesn't perform well in this area. Any thoughts or observations by owners would be most appreciated!

etocynned
02-17-2013, 10:07 AM
I found the headphone output adequate through hd201s. I did notice a small amount of him but it wasn't distracting. I had trouble intermittently with the speakers not muting when the headphon jack was inserted. It was an on again off again thing.

On the whole I'm converted and won't be buying anything else without tubesEVER again. Thinking of a SET amp through some high sensitivity full rangers.

Pen Name
02-17-2013, 05:26 PM
I gave the I-12 to my son as a grad present, so I have been unable to play with it more. The Hum may perhaps be remedied by using higher impedance headphones, I suppose. It was definitely possible to reduce the hum by using less output on the amp and more on my cordless headphones.
The intermittent muting of the speakers was traced to using the 4 Ohm speaker connects instead of the 8 Ohms. I cannot remember if it was the 8 Ohm or 4 Ohm tab that did not mute the speakers. Definitely some odd wiring though.
I still miss the little thing, and would buy it again if I could find a space for it. Space is taken up by the 300B Shuguang, which to my ears sounds even nicer. But at $1000, it should sound nicer... And I never upgraded the tubes in the I-12...

BluesDaddy
02-17-2013, 07:36 PM
Thanks for the responses. You both are making it hard for me not to pull the trigger on one! :scratch2:

Pen Name
02-18-2013, 02:27 PM
Thanks for the responses. You both are making it hard for me not to pull the trigger on one! :scratch2:

I have never tried shooting an amplifier to reduce its hum. Let me know how that works out...:lmao: