Question for QLS 1 owners?

R

Robmag

Active Member
Once I got my Kappa 8's up and running in my workout room, I knew I needed to replace my speakers in my main listening area. I love the Kappa Sound. So smooth and Bold!
I have been looking for a set of Kappa 9's and come across a beautiful set of QLS 1's. These speakers look great from the photos I have seen and I have been told the drivers are all functioning. The only thing the owner said they might need is the corssover's recapped.
I have never heard the QLS 1 and based on what i have read, the QLS is like a rolls royce and the kappa 9 is like a porche. I am hoping some of the QLS owners can give me a direct comparison of the two?
I listen to all music but I particularly like music from the 70's, Bob Segar and the Eagles for example.

The other concern is having enough power for the QLS? Would my two Classe DR-8's have enough power to drive them? Here is the specs:

8 OHMS- 280 Watts
4 ohms 560 Watts.

Thanks
Rob
 
Robmag said:
I listen to all music but I particularly like music from the 70's, Bob Segar and the Eagles for example.

The other concern is having enough power for the QLS? Would my two Classe DR-8's have enough power to drive them? Here is the specs:

8 OHMS- 280 Watts
4 ohms 560 Watts.

Thanks
Rob
Click to expand...

Important to note those power specs are in bridged mode and the amps are stable at 2 Ohms and 750 watts. High current amps. Looks to me like you made a good choice to be driving old, large Infinity.

Curious to know how good the QLS1 are as hard rock speakers. When you listen to a lot of hard rock from well before the loudness wars you want speakers with very good dynamics under volume. Seems like the QLS1 should perform well for all kinds of music. You may find they have better dynamics than your 8 Kappa.

You bring up an interesting question for the group. If given the opportunity to choose between the two in good working order and you didn't have to worry about amps, 9 Kappa or QLS1?
 
Both good performers with the Kappas being a bit more sporty, but are much more temperamental about amplification as they cause amps to be bit unstable pushing maximum speed on the straight a way, keeping the the car analogy:)
The QLS-Is sound lovely and I don't think much of car analogies.
 
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I have found the QLS1 sound great for classical, bluegrass, jazz, vocal, and other acoustic type music. They are very smooth, detailed and accurate. They have a kind of dark sound to them, with nothing in the background.

However when I want to ROCK some Allman Brothers, Neil Young or Gov't Mule, I pull out my good old ESS Heil AMT3 Rock Monitors, they are super bright and "West Coast" sounding.

I've never had the pleasure of hearing the big Kappa's, They are known to dip to almost one ohm at two specific frequencies.

Your amplification is certainly up to the task either way. The other thing the big QLS1's need is space, my room is on the small side at 19' X 22' X 8.5'! It can really take a while to get them dialed into your room. They have attenuators on the EMITs, domes, and "mid-bass coupler", switchable rear tweeters and a three way adjustable crossover point between the EMITs and domes. You need to be patient and experiment a lot.

Any of these old Infinity speakers will need their electrolytic caps replaced, the ones in my QLS1's were ALL leaking. The film caps on the domes and EMITs should be OK though, If you do replace them, use film caps, they really effect the "Infinity sound".

There are a few things to watch out for:

There are four different types of woofers, 40 oz. magnet with a 2" vc and a 30 oz magnet with a 1 1/2" vc. Either type was built with paper or poly cones. They all sound about the same but they should be matching.

There are (at least) two different crosovers, the early type with 1600 uF on the Watkins 2 ohm vc and the later one with 1,100 uF. Check inside before you buy parts (Ask me how I know!) The construction quality on my crossovers was not at the level you might expect for speakers which cost as much as a small car when they were new! Check for enough solder, I had to reflow a few of the joints in there.

The pots in the crossover are known to corrode, but they were made to be easy to disassemble and will clean up nicely. Which is a good thing because it's hard to find replacements which are small enough to fit in the crossovers.
 
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That's an extraordinary collection. When I see someone selling off like that I have to wonder what happened to make it necessary. There are a couple of AKers with similar forum names (one is exact) to the seller's name but neither have ever posted.

Pricing seems a little high. Perhaps the seller will haggle? The RS4.5 have an unusually steep price. They're in good shape except for the gouge and scratches in one speaker, and the foam padding on the upper face of the speakers looks as if it may be on the way out. It degrades over time and falls apart, a poke may easily take a chunk out of it, may be due for replacement. They have the newest generation black poly Watkins woofers, obviously replaced somewhere down the line (currently $750 for a new pair) and the set comes with the active crossover. The RS4.5 need proper placement for the EMIM rear wave to reflect from a back wall and a fairly large room. Maybe acoustical room treatments to get everything balanced properly... It's a serious high end speaker that got high end consideration in its day. Stereophile used it as their reference speaker in their test system for a while, albeit after suffering through Infinity higher-ups popping in after complaints to make a number of revisions to the crossovers. Owners can love them or hate perceived shortcomings of the RS4.5, possibly if they aren't set up properly. I was certainly discouraged with mine but not willing to give up on them. Mine had huge bass presence that some owners have found lacking.

I think Infinity models with EMIMs are probably not a good first choice for someone who listens mostly to classic rock. EMIMs image like a champ but the excursion is too limited for loud rock music and won't get as loud as the Kappa or (I expect) RSII, if that's important to the way you listen to classic rock music. I expect the RSII to be excellent for rock, have very good dynamics and great midrange presence because of all the poly cone drivers. The RSII may have better perceived dynamics for rock music than the Kappa, even at moderate listening levels. Considering the RSII while having a set of 8 Kappa may be something of a lateral move when you're looking for an upgrade to put in the main listening room. I know from experience that the 8 Kappa will get very loud and perform very well at high volume with proper amps pushing them. I've never seen comment that the RSII was available in black as some of the other classic models were occasionally available.

The 9 Kappa have Vifa or Scan Speak substitutes in place of the Polydomes. I haven't heard them but I consider them a compromise or a poor choice for solving a Polydome problem. Those drivers don't spec like the Kappa Polydome but there are quite a few people who were happy with them. Not a value added modification, IMO.

The QLS1 look awesome. Surely shouldn't disregard the RSII, especially if you want to save money. You're very lucky to have the opportunity to choose from this nice collection of classic Infinity speakers.
 
Good point! The RSII might be great for "classic rock". They are also the only one of your four choices which doesn't have any "unreplacable" parts.

The RSII is the Rodney Dangerfield of the high end Infinitys, they don't get no respect, ya know what I mean?

I think those poly cone mids were really a stop-gap measure until the EMIMs came on line. Are they just a poly cone version of the old Philips mids?
 
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Newk_Yuler said:
That's an extraordinary collection. When I see someone selling off like that I have to wonder what happened to make it necessary. There are a couple of AKers with similar forum names (one is exact) to the seller's name but neither have ever posted.

Pricing seems a little high. Perhaps the seller will haggle? The RS4.5 have an unusually steep price. They're in good shape except for the gouge and scratches in one speaker, and the foam padding on the upper face of the speakers looks as if it may be on the way out. It degrades over time and falls apart, a poke may easily take a chunk out of it, may be due for replacement. They have the newest generation black poly Watkins woofers, obviously replaced somewhere down the line (currently $750 for a new pair) and the set comes with the active crossover. The RS4.5 need proper placement for the EMIM rear wave to reflect from a back wall and a fairly large room. Maybe acoustical room treatments to get everything balanced properly... It's a serious high end speaker that got high end consideration in its day. Stereophile used it as their reference speaker in their test system for a while, albeit after suffering through Infinity higher-ups popping in after complaints to make a number of revisions to the crossovers. Owners can love them or hate perceived shortcomings of the RS4.5, possibly if they aren't set up properly. I was certainly discouraged with mine but not willing to give up on them. Mine had huge bass presence that some owners have found lacking.

I think Infinity models with EMIMs are probably not a good first choice for someone who listens mostly to classic rock. EMIMs image like a champ but the excursion is too limited for loud rock music and won't get as loud as the Kappa or (I expect) RSII, if that's important to the way you listen to classic rock music. I expect the RSII to be excellent for rock, have very good dynamics and great midrange presence because of all the poly cone drivers. The RSII may have better perceived dynamics for rock music than the Kappa, even at moderate listening levels. Considering the RSII while having a set of 8 Kappa may be something of a lateral move when you're looking for an upgrade to put in the main listening room. I know from experience that the 8 Kappa will get very loud and perform very well at high volume with proper amps pushing them. I've never seen comment that the RSII was available in black as some of the other classic models were occasionally available.

The 9 Kappa have Vifa or Scan Speak substitutes in place of the Polydomes. I haven't heard them but I consider them a compromise or a poor choice for solving a Polydome problem. Those drivers don't spec like the Kappa Polydome but there are quite a few people who were happy with them. Not a value added modification, IMO.

The QLS1 look awesome. Surely shouldn't disregard the RSII, especially if you want to save money. You're very lucky to have the opportunity to choose from this nice collection of classic Infinity speakers.
Click to expand...

What is a fair price for the RS 4.5?
 
chef free said:
Good point! The RSII might be great for "classic rock". They are also the only one of your four choices which doesn't have any "unreplacable" parts.

The RSII is the Rodney Dangerfield of the high end Infinitys, they don't get no respect, ya know what I mean?

I think those poly cone mids were really a stop-gap measure until the EMIMs came on line. Are they just a poly cone version of the old Philips mids?
Click to expand...

There may be people who look at the RSII and see the more conventional, or maybe less exotic, not high-end-ish drivers and immediately think less of them. I don't have the technical knowledge to explain the design intentions of the open back on a wing dipole design but there were intentional advantages beyond a simple dipole. Infinity used that design on a number of upscale classic models right up to the IRS. There's probably a proper explanation buried in the forum. This seller's RSII has foam padding added on the back of the mid drivers that's apparently there to mute the rear wave. That defeats a purpose of the speaker's design.

According to Wikipedia a disadvantage to a dipole design is a loss of sound pressure relative to a similar enclosed driver, so that may have something to do with using 3 poly mids per speaker. That also means they might not be as dynamic as I've been thinking they should be. The RS1.5 and the Infinitesimal 0.3 use one of the poly mids in sealed enclosures which is what I've based the way I've been thinking of the poly mids all along. The RSII may need 3 of them per speaker to produce similar performance. I'm just speculating out loud, though. One thing I neglected to mention earlier is the RSII is another speaker than needs proper space from a back wall, although this set has been modded to eliminate that need (whether it's good or bad). Robmag might ask the seller why the padding is there.

AFAIK without looking up the part numbers the poly cone mids are the same driver anywhere else you see them in Infinity models from that era.
 
Robmag said:
What is a fair price for the RS 4.5?
Click to expand...

I sniped $2150 in a bid war on eBay with the active crossover back in the mid oughts, all in good working condition at the time of purchase, or so I assumed because all drivers were working. Watching eBay over the years has shown similar or lower prices, sometimes much lower depending on condition. You could look it up in the Audiogon Bluebook listings but it will cost $5 for a one-off. If you do it would be cool if you let us know, please.

Michael Marks has a set of 4.5 on eBay right now with a typical MM bloated asking price and no active crossover. That is the set Chef Free is referring to. As rare as the RS4.5 are suppose to be with only 300 sets made, they turn up on eBay with some regularity and seem less rare than many other mid and upscale classic Infinity models.
 
I hate to say this, BUT MM is on the right track, you will never ever buy any Infinity model that wil out image the 4.5's. I know this for a fact, I've heard them all. I also have several of the big Apogee's and they can't touch them, nor can the Acoustats, It's a shame when people want top quality sound and want it for cheap just because it's old.
QLS for 1300 is a no brainer, buy them, thier not in the league of the 4.5 but they can bang out some pretty good sound, especially rock, the dome's will be quite noticable, as you can hear the air rushing from them, at least I can. Al
 
Newk_Yuler said:
Pricing seems a little high.
Click to expand...

If you're including the QLS-1's in that comment I beg to differ. As the owner of QLS-1's (which I totally refurbished), Altec 19, JBL L250, and Acoustat Spectra 22 I can say without hesitation that's a very, very fair price for a set of QLS-1's in that condition considering the level of performance they are capable of. Biamped with a pair of Threshold s/300's and in an acoustically treated room they aren't perfect at anything but damn near magnificent at everything.

And they are perfectly competent with hard rock. When offered conditions that enable them to shine, playing Tool's Undertow or something as edgy as Ministry through them proves this in spades.
 
InAp said:
I hate to say this, BUT MM is on the right track, you will never ever buy any Infinity model that wil out image the 4.5's. I know this for a fact, I've heard them all. I also have several of the big Apogee's and they can't touch them, nor can the Acoustats, It's a shame when people want top quality sound and want it for cheap just because it's old.
QLS for 1300 is a no brainer, buy them, thier not in the league of the 4.5 but they can bang out some pretty good sound, especially rock, the dome's will be quite noticable, as you can hear the air rushing from them, at least I can. Al
Click to expand...

I've read from more than few different sources that the 4.5's ask a lot from those EMIMs (perhaps too much if higher output levels are attempted) by having them reach down to mate with the Watkins drivers. It's no big secret the EMIMs aren't exactly champs down there where a bit of excursion is necessary for impressive dynamics in that region of content. I've never heard 4.5's, but I can see where such an observation could have some validity since Infinity came out with the L-EMIM after the 4.5's.
 
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Regarding the foam on the back of the RSII, the original set up was another grill with a foam insert in it. All the foam inserts have long turned to dust but many still have the grills. Mine have the grills. They are a wonderful speaker and will embarrass many of those slim puny speakers selling for thousands these days...

If you are tight on space and cash they don't get much better for the size or price.
Jim
 
InAp said:
I hate to say this, BUT MM is on the right track, you will never ever buy any Infinity model that wil out image the 4.5's.
Click to expand...

I'm not disputing that but for Robmag's sake, he's mostly a rocker and the expense of a finer speaker for rock music isn't necessarily a proper direction when pursuing classic Infinity. If he had said he listened mostly to classical binaural or otherwise very precise stereo recordings then models that excel at imaging are much more important.
 
tomlinmgt said:
If you're including the QLS-1's in that comment I beg to differ. As the owner of QLS-1's (which I totally refurbished), Altec 19, JBL L250, and Acoustat Spectra 22 I can say without hesitation that's a very, very fair price for a set of QLS-1's in that condition considering the level of performance they are capable of. Biamped with a pair of Threshold s/300's and in an acoustically treated room they aren't perfect at anything but damn near magnificent at everything.

And they are perfectly competent with hard rock. When offered conditions that enable them to shine, playing Tool's Undertow or something as edgy as Ministry through them proves this in spades.
Click to expand...

I speculated that the cost was a little high because I've seen QLS1 go for significantly less on eBay, in various condition. There was a set that briefly appeared on eBay a couple of years ago in as good condition as these before Robmag with a bin of $700. They were local to me, too and the darn things instantly disappeared. I must agree that a set of QLS1 in excellent shape are likely worth what this seller is asking for them. I'll also agree that they should be right at the top of the list for what to consider grabbing from what's available. I'll suggest that if Robmag was thinking of getting the RS4.5 at the asking price that he might consider getting the QLS1 and the RSII. Excellent opportunities like this are rare and become more rare as time passes.
 
slimpikkins said:
Regarding the foam on the back of the RSII, the original set up was another grill with a foam insert in it. All the foam inserts have long turned to dust but many still have the grills. Mine have the grills. They are a wonderful speaker and will embarrass many of those slim puny speakers selling for thousands these days...

If you are tight on space and cash they don't get much better for the size or price.
Jim
Click to expand...

I wasn't aware of the rear grill. Thanks for the information on the RSII. First hand testimony is exactly what Robmag needs. He's living what many of us can only dream.
 
tomlinmgt said:
I've read from more than few different sources that the 4.5's ask a lot from those EMIMs (perhaps too much if higher output levels are attempted) by having them reach down to mate with the Watkins drivers. It's no big secret the EMIMs aren't exactly champs down there where a bit of excursion is necessary for impressive dynamics in that region of content. I've never heard 4.5's, but I can see where such an observation could have some validity since Infinity came out with the L-EMIM after the 4.5's.
Click to expand...

That describes my experience but I'm reasonably certain there were issues outside the 4.5 that were causing problems. That's also why I think of them as not a particularly good choice for rock music. When Stereophile was using the RS4.5 as their reference speaker one of their early problems was a big absence of mid bass. They apparently got past it, though. There are more RS4.5 owners who love them than there are those who are frustrated by their performance. When I pull mine out of moth balls one of the first things I'll do is determine the crossover version. If it turns out to be an early version then I'll know what was most of the problem.

I expect models using many more EMIMs (like the IRS) didn't suffer the mid bass excursion issue because there are so many more of them moving air. If any of you visit Colorado, go out of the way to drop by the PS Audio facility and bother Paul McGowan to audition his IRSV for you. I'm sure it's an unforgettable experience.
 
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