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DIY High or Low Ouput Moving Coil Phono Stage

I have built two of these so far one for my main system and one for the bedroom system, both using Benz Micro Ace's, the one in my main system is the latest S medium output version and in the bedroom is the high output earlier one with the Van Den Hull stylus.

Both systems now sound fantastic, so much so I have been listening to all my vinyl again, it's like having a whole new collection.

I have ordered a pair of AD797's as per Jim Reeves findings, Jim is the Op Amp king, and some LME49710's to try out as well.

As far as other phono stages I have compared it's like Goldilock's said, "This one is just right".:D
 
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Grainger is a gracious and generous host. Treated me to one killer burger! :thmbsp:
His Bottlehead amps sounded fantastic! The Hypno-clone was running 4 Opa134's for op-amps and still sits in it's unassuming cardboard box. Dire Straits, Love Over Gold sounded delicious. I now look forward to more work trips to Knoxville.

Thank you, Grainger! :music:
 
HypnoToad said:
I have built two of these so far one for my main system and one for the bedroom system, both using Benz Micro Ace's, the one in my main system is the latest S medium output version and in the bedroom is the high output earlier one with the Van Den Hull stylus.
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Interesting. Are you talking about the phonoclone or the VSPS? I thought the phonoclone was for low output moving coils only. I have a medium output Ace and was going to try instead the VSPS. Maybe I better go for the phonoclone?

Jeff
 
jmathers said:
Interesting. Are you talking about the phonoclone or the VSPS? I thought the phonoclone was for low output moving coils only. I have a medium output Ace and was going to try instead the VSPS. Maybe I better go for the phonoclone?

Jeff
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If you have a medium output Ace which is 0.8mv's it's fine with the phonoclone, you couldn't use the VSPS with it, not enough gain. I even use my high output Ace with it and it's 2.4mv's.
 
HypnoToad said:
Good to hear that you are safe.

Those Polyesters may be too revealing, if they are try these 667-ECW-F2105JA 1UF's and these 667-ECW-F2104JAQ 0.1uf in parallel as a bypass, that's what I am using now, both revealing and smooth.
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Mr. HypnoToad,

I have my PhonoClone boards in and am just now getting ready to order parts. Sorry for the lame question but how many of each (of your recommended P/Ns) are required per board and at what board location? Thanks in advance...

Can't tell you how jazzed I am about this. I don't even have this built and I ordered up an Ortofon Salsa. Can't wait...
 
Grainger49 said:
I also haven't found the "formula" to calculate the feedback resistor that sets the gain for the first stage. There is a note on one of the RJM Audio pages stating it should be 180 times the internal resistance of the MC cartridge. But that doesn't take into account the output level of the cartridge. Can someone point me to the equation for Rf for the first stage taking the output and source resistance into account?
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Grainger-

I followed this for a total gain of 60db-

"It has not been possible to get the high gain version of the phonoclone to work, though. Also, personally, I prefer to lower the first stage gain to 30 dB or thereabouts ( R2 = 30 x Rs ). Most people should have no problem just using the recommended R2 value of 1.5 kohms."

33x 30= 990. I went with a 1K resistor.
 
Bluespower said:
Mr. HypnoToad,

I have my PhonoClone boards in and am just now getting ready to order parts. Sorry for the lame question but how many of each (of your recommended P/Ns) are required per board and at what board location? Thanks in advance...

Can't tell you how jazzed I am about this. I don't even have this built and I ordered up an Ortofon Salsa. Can't wait...
Click to expand...

You have the boards from RJM Audio I take it, there is a BOM with part numbers for Mouser I got from the DiyAudio site that I can't find now as the thread is so long. You need that as your building on Richards boards.

Let me know your email address and I will send it to you.

The gain calculator is here if anyone needs it, I just found that again:

http://www.diyaudio.com/forums/analogue-source/57398-phonoclone-vsps-pcb-help-desk-105.html#post1726608
 
Fasterdamnit said:
Grainger-

I followed this for a total gain of 60db-

"It has not been possible to get the high gain version of the phonoclone to work, though. Also, personally, I prefer to lower the first stage gain to 30 dB or thereabouts ( R2 = 30 x Rs ). Most people should have no problem just using the recommended R2 value of 1.5 kohms."

33x 30= 990. I went with a 1K resistor.
Click to expand...

I have some 1k scavenged that are awfully nice. I used the spreadsheet HT sent me and got 1740. Since there is so much gain there either would do fine in my system. I have been using the info from Vinyl Engine to make the calculations. I really am going to dig out the Denon info today so I can verify the source impedance and output. I know I have it in a box... somewhere....
 
Grainger49 said:
I have some 1k scavenged that are awfully nice. I used the spreadsheet HT sent me and got 1740. Since there is so much gain there either would do fine in my system. I have been using the info from Vinyl Engine to make the calculations. I really am going to dig out the Denon info today so I can verify the source impedance and output. I know I have it in a box... somewhere....
Click to expand...

It all goes on the resistance of the cart, I tried my homc which is 2.4mv and 90 ohms on the same stage as the medium output one which is 0.8mv and 24 ohms. I get more volume from the medium output than the high output.

Denon DL-103's that are sold now are 40ohms and 0.3mv's and should have R1 40ohms and R2 1.3k. That's what I get anyway.
 
I just found the manual that came with the cartridge and SUT. Back in 1986 the output was 0.3mV at 40 ohms impedance, the same as HT just posted. Glad to see some things don't change. I am concerned that the stated impedance is what the cartridge wants to "see" rather than the source impedance.

Well, I'm still reading and there is the chart showing impedance versus frequency, it is 40 ohms across the audible band (to 30k Hz). I will check using the spread sheet after getting back from a doctor's appt.

HT, thanks yet another time!
 
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Listening to some old albums and it's amazing how much more it extracts from the grooves, I used to wonder what those phono stages that cost thousands sound like. And if there worth it, now I know.:banana:

Oops gotta go, Goodbye Yellow Brick Road is calling me.:music:
 
HT,

"Bread and Dripping?"

I'm looking forward to my own. I am collecting parts and I'll soon get to it. Maybe I will make a long run at the local supplier. I'd prefer better resistors in the crucial signal path positions but I'm itching to get it running.
 
Grainger49 said:
HT,

"Bread and Dripping?"

I'm looking forward to my own. I am collecting parts and I'll soon get to it. Maybe I will make a long run at the local supplier. I'd prefer better resistors in the crucial signal path positions but I'm itching to get it running.
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Dripping is just another name for fat, the stuff left in the pan after cooking beef or pork and some poor folks in Great Britain used to spread it on bread like peanut butter.

I have used Vishay Dale resistors in mine but wonder if they really make any difference. Some people use carbon composition for the 47 ohm ones.
 
Ah, Ha! Even though I have lived my whole life in the South I hadn't heard that phrase. I like it! I was aware of using grease instead of butter.

I'm convinced that film resistors are better than carbon comp. I'm not trying to start an argument, that is just my opinion. The CC resistors drift with time and heat. That wouldn't be the case here but it was in tubed electronics. The less material that the signal travels through the better IMHO. That is why I have bookmarked lower power rated resistors for the final edition of this board for me.
 
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I couldn't bring myself to use the CC resistors even though they were recommended, I think the Panasonic Metal Films are as good as any.

The Wima FKP2 is what I used for the RIAA caps, they sound a little closed in at first but quickly open up.

I also like the Panasonic ECW as well for the DC blocking output caps.

Other than that I am going to try Jim Reeves suggestion of AD797's in the output section. And will try some LME49710's in the input section. But I really can't see it getting a whole lot better than what it is, it's at the pinnacle now IMO, but you never know until you try.

Some people spend a fortune on exotic parts but being a cheap @ss I find it hard to open my wallet that wide:D
 
I've been running AD797's out and LME49710's in for a few days, although I haven't had enough time with them yet. I really like the difference the AD797's made, but as expected the LME's may be a bit drier than the OPA27's. There really wasn't a very big difference on the input side that I could hear (aside from the fact that the AD797's won't function there). Does that seem logical?
Anyway, I didn't notice a obvious difference in gain with the swaps.
Hope to have more time this weekend to try combinations:
AD797
LME49710
AD711
AD8031
and my 3 cell LiPo packs
Should there be a sonic difference with more DC voltage?
Is there a 'best' voltage for this circuit?
 
jimreeves said:
I've been running AD797's out and LME49710's in for a few days, although I haven't had enough time with them yet. I really like the difference the AD797's made, but as expected the LME's may be a bit drier than the OPA27's. There really wasn't a very big difference on the input side that I could hear (aside from the fact that the AD797's won't function there). Does that seem logical?
Anyway, I didn't notice a obvious difference in gain with the swaps.
Hope to have more time this weekend to try combinations:
AD797
LME49710
AD711
AD8031
and my 3 cell LiPo packs
Should there be a sonic difference with more DC voltage?
Is there a 'best' voltage for this circuit?
Click to expand...

Don't worry that you couldn't get the AD797's to work, Richard the brains behind this couldn't get them to work either, he said he initially intended to use them. But the dc offset, high bandwidth and other problems couldn't be sorted out.

Higher voltage around 12v per side is about all I think you need, and more current in reserve is always a good thing. Let us know how it sounds.
 
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