DIY phono stages... help me straighten them out.

The number of tempting DIY phono stages seems to be growing every day. I'm having a hard time keeping it all straight and as I get closer to launch I'm more confused than ever. To be honest I wasn't sure if I should post here or in DIY. But, I chose this forum as it's more about matching the system than the actual build.

SO, I am focused mainly on the scratch builds (with access to PCB boards and build threads) than full fledged kits. I like the idea of parts selection and custom enclosures at this point. I'm also sticking with SS over tubes to keep it simple.

What I have so far is....

-Boozehound, cheap and simple. MM, but has optional additional MC board available. Adjustable gain? Can be operated on batteries or can build PS. Seems to be well liked.

-Phonoclone? I'm totally confused about this. I take it that this started as a knock off of the Phonocube? How many iterations have there been? Is this what started the Hypnotoad projects?

-AD797 based builds, not sure if these are stand alone projects or if they are takes on the other ones.

-Hypnotoad phono stages. I think there are now a couple of them? I know about the HTMCPS (HypnoToadMovingCoilPhonoStage). Is there a MM version? How many phono stages has this guy brought to the table?

I'm sure there are others. Yes, yes, I know about Bottlehead and Hagerman's among others. Again, I am looking at scratch builds either P2P or with boards (even though the Boozehound comes with parts I'm still counting it...)

What other ones would you add to the list?
Which ones have you built?
Impressions?
Comparisons?
Historical progression?
Great ones that have been forgotten?

I know this is a tall order. But, it would be nice to have a comprehensive thread. Would this make a good sticky?

Thanks,
Dogwan

I have the boozehound jFet stage for MM and Hypnotoads stage for MM. I don't think you can go wrong with either of them. I like the jFet stage but I've been running Hypno's for quite a while and am quite happy with it.

Really this is a question on which stage you will build first. DIY is addictive and these are relatively inexpensive. :yes:

I have the CNC MM of Hypnotoads. I've been using it with batteries. Really works well.

In my opinion, the CNC phono stage is a fantastic phono section. You can get the PCB by sending a PM to Sach888. It's not a kit -just a bare board, so you can pick and choose the components. He will provide a BOM which is very good - you may not want to change anything. It was originally built to operate on 2 9V batteries but many are using SLA batteries or the OPS (Omishra Power Supply). The OPS board is also available from Sachin. I think (but am not sure) that the CNC is loosely based on the Phonoclone.

The Boozehound Labs phono section is also very nice - it's a kit but has some excellent caps.

The Hypnotoad HTMCPS is an early version of what's now called the HQMC (high quality moving coil) - but obviously for MM. I have the HQMC and it's fantastic. I think the AD797builds you are referring to is the HQMC - it uses that opamp along with LM49990.

I think the best answer is to build them all - you won't have very much invested and it's a great amount of fun. There's lots of help available on AK for the CNC and HQMC. Good luck and have fun.

Don't forget the Pass Labs DIY phone stage... The Pearl 2.

Regards
Mister Pig

If you haven't, the TI/National app note here is a good read.

I use a fairly conventional active eq stage using the LME79410, but I run it inverting, and buffer the cartridge with a X3 non-inverting gain stage first. It's as good as any preamp I've heard. Not too tough to wire up, though I etched a board, but you could easily wire it up with perfboard.

I would not build a phono stage today without buying Doug Self's low level signal book first. I didn't have it when I built mine. He offers some very interesting techniques for reducing noise and does the numbers to show why passive networks can't offer the performance of active eq. (yes, flameproof undies are on, as I know how popular passive networks are)

I've heard a Pass Pearl. Sounds quite nice indeed.

I am in the same boat as the OP. I spent a week straight trying to read about DIY stages and I am not sure which one to pick.

One that's not on the list that I keep reading about is the ESP P06 with it's split active/passive EQ. Sounds interesting.

Also how would any of these compare to the Rega Fono or Fono mini? I keep reading the Rega is warm, I think I might need warmth in my system.

I really like my CNC. Made mine not too long ago: http://www.audiokarma.org/forums/showthread.php?t=600096. Listening to it with a Sansui AU-717 and it sounds really good. Also sounds great with tube amps.

Before the tube stage I have now, I had a Boozehound fet stage, I used Silmic ll filter caps....a mix of Takman REX and Shinkoh resistors, Vishay caps in the RIAA and Hovland Musicaps coupling with Duelund VSF output caps........and ETI RCA sockets, wiring was Neotech 7N.
Run off two 12v SLA batteries in series for 24v it sounded very nice indeed

Mister Pig said:

Don't forget the Pass Labs DIY phone stage... The Pearl 2.

Regards
Mister Pig

Click to expand...

Is that one still available? How's it compare to the others mentioned by the OP?

Just get the Hagerman Bugle 2 and live happily ever after.

fredjones said:

Just get the Hagerman Bugle 2 and live happily ever after.

Click to expand...

I am considering that and just be done with it, but some of the other DIY stages are significantly less expensive. Is the Bugle 2 that much better?

Interestingly, I wonder if anybody can chime in on the merits of design and how each benefits sound characteristics, for example the Bugle 2 with the three op amp design and passive EQ and how it sounds vs the ESP P06 with two op amps and a split active/passive EQ vs the Boozehoud discreet JFet design vs the very simple and inexpensive CNC and it's basic design of two op amps and passive EQ, etc.

Which of these designs is the most warm, the most neutral, the most detailed, the greatest soundstage??

gnuyork said:

I am considering that and just be done with it, but some of the other DIY stages are significantly less expensive. Is the Bugle 2 that much better?

Interestingly, I wonder if anybody can chime in on the merits of design and how each benefits sound characteristics, for example the Bugle 2 with the three op amp design and passive EQ and how it sounds vs the ESP P06 with two op amps and a split active/passive EQ vs the Boozehoud discreet JFet design vs the very simple and inexpensive CNC and it's basic design of two op amps and passive EQ, etc.

Which of these designs is the most warm, the most neutral, the most detailed, the greatest soundstage??

Click to expand...

As you're already aware, there are many different ways to make a phonostage. If you compare one design with passive eq to another with active eq it would be tempting to ascribe any difference you hear to the active/passive elements of the design, but you would probably be wrong - there are likely to be enough differences elsewhere to make a direct comparison meaningless. Even two identical designs can perform differently if their physical circuit layouts are different. This applies particularly to the way earth tracks are routed on the PCB.

In short, it's difficult to make any definitive claims about active vs. passive eq, or one op-amp vs. another op-amp, or bipolar transistors vs. JFETs, or anything else. But the beauty of DIY is you can experiment and learn for yourself.

Oh, here I go again. Phono preamps either adhere precisely to the RIAA curve, offer low distortion and negligible noise and don't overload with the actual signals present, or they don't. They offer the correct load to the cartridge, hopefully adjustable. Preamps that accomplish that task don't have a sound and should be indistinguishable. They aren't warm, cold, detailed, muddy or grapefruit. Not that it's a trivial task, but you can deduce quite a lot by looking at the schematics and running some numbers and simulations.

ConradH said:

Oh, here I go again. Phono preamps either adhere precisely to the RIAA curve, offer low distortion and negligible noise and don't overload with the actual signals present, or they don't. They offer the correct load to the cartridge, hopefully adjustable. Preamps that accomplish that task don't have a sound and should be indistinguishable. They aren't warm, cold, detailed, muddy or grapefruit. Not that it's a trivial task, but you can deduce quite a lot by looking at the schematics and running some numbers and simulations.

Click to expand...

Yes, that makes a lot of sense, but it seems to fly in the face of so many people's experience. I think you touched on something when you said "offer low distortion". Distortion comes in many different forms and two pre-amps with quoted distortion figures of 0.01% could have very different types of distortion. At least, that's the explanation I offer to account for the differences people hear.

I use the ESP 06 with eq adjustments for 78 curves and have been extremely pleased with the sound-to-price ratio.

http://sound.westhost.com/project06.htm

http://www.mds975.co.uk/Content/vinyl05.html

rothwellaudi said:

Yes, that makes a lot of sense, but it seems to fly in the face of so many people's experience. I think you touched on something when you said "offer low distortion". Distortion comes in many different forms and two pre-amps with quoted distortion figures of 0.01% could have very different types of distortion. At least, that's the explanation I offer to account for the differences people hear.

Click to expand...

Very true. The reason I picked the very arbitrary number of 0.01% is that even a bad spectrum probably won't be very bad at that level. From another thread, it's also important that the performance be very good right down into the noise. What the thing does near full output, where it's easiest to measure, is probably far less important.

ConradH said:

Very true. The reason I picked the very arbitrary number of 0.01% is that even a bad spectrum probably won't be very bad at that level. From another thread, it's also important that the performance be very good right down into the noise. What the thing does near full output, where it's easiest to measure, is probably far less important.

Click to expand...

I agree entirely. I think - mostly speculation btw - that people find valves appealing because the distortion is low at low signal levels, and what happens near full output is, as you say, far less important.

Wow, lots of great answers and information. I think I'm a little clearer now on some of it.

Re: Hypnotoads, am I correct that there are basically 3 different stages?

-CNC for MM
-HTMCPS is the predecessor to the....
-HQMC (and this started out as the AD797 ?)http://www.audiokarma.org/forums/showthread.php?t=501186

Now, which phonostage is this related to/ or turn into?
"Another Super High End Phono Stage! No expense spared..."
http://www.audiokarma.org/forums/showthread.php?t=371889


This is great... I hope we can keep it going. My only request is we keep the subjective/objective debate out of it. The point wasn't to ask which is better, but to straighten out the "family tree". Whoever said "Just get the Hagerman Bugle 2 ..." obviously didn't get it.