Old VSPS
Hello
You probably haven't seen a VSPS this old for a while.
I found myself disappointed with my vinyl setup, and remembered this old half-finished build. I need to order a pair of OPA314 anyway, and I have a 50VA 20+20v transformer, so I'll might as well use a pair of 18v brides for perhaps slightly better performance? I'll also use some high grade output caps.
Anyway, my question is this, this uses the old RIAA values of 1nf and 330p and corresponding resistor values. Are the current values somehow better, or should I just - "let it be"?
Thanks!
Hello
You probably haven't seen a VSPS this old for a while.
I found myself disappointed with my vinyl setup, and remembered this old half-finished build. I need to order a pair of OPA314 anyway, and I have a 50VA 20+20v transformer, so I'll might as well use a pair of 18v brides for perhaps slightly better performance? I'll also use some high grade output caps.
Anyway, my question is this, this uses the old RIAA values of 1nf and 330p and corresponding resistor values. Are the current values somehow better, or should I just - "let it be"?
Thanks!
Yeah, that's from so far back I can't remember. Did I originally use 1 nF and 330 pF? It must have been for only a brief period.
Essentially, that puts the RIAA network at 3x the impedance of the current one. I don't expect it would make much difference. I changed it to try to achieve lower noise.
Note that much more recently the RIAA network was changed again to remove the 50k time constant. This change does improve the sound slightly.
So you could modernize your build use the current values, but honestly I can't really say it would be worth the trouble now you have everything soldered. If you want to remove the 50k time constant but keep the same 330 pF and 1nF caps you have, let me know the resistance values you have and I can tell you the revised values you need to substitute.
/R
Essentially, that puts the RIAA network at 3x the impedance of the current one. I don't expect it would make much difference. I changed it to try to achieve lower noise.
Note that much more recently the RIAA network was changed again to remove the 50k time constant. This change does improve the sound slightly.
So you could modernize your build use the current values, but honestly I can't really say it would be worth the trouble now you have everything soldered. If you want to remove the 50k time constant but keep the same 330 pF and 1nF caps you have, let me know the resistance values you have and I can tell you the revised values you need to substitute.
/R
According to my mailbox, I bought it from you in 2006.
It's strange I never bothered to test it back then when it was pretty much done (and I was constantly tweaking my vinyl setup... Currently I have toddlers, so it is usually stowed away) but I'll go ahead now!The original instruction with the values I currently have is here (hi-Z values 330k, 2.2M, 330p, 1n + Allen Wright): The VSPS
Don't bother recalculating, I'll just to simply replace it with the current parts, but I guess it could be troublesome to fit three parallel 1nf on this board... I suppose I could put the two extra ones underneath the board. Thanks for the offer even though this must be way out of warranty.
The rest of my system is extremely revealing these days, so I might as well put those extra minutes and cents in and try to get the most out of it. I will be replacing the LM7x12s (with 7x18s, mainly not to just waste the spare voltage as heat) and the output caps anyway - I assume going to 18v doesn't change the feedback loop/ riaa correction? The rest of the vinyl system is a Denon DL160 high output MC pickup (on a heavily tweaked Rega planar 2) so I think 47k should be the right input impedance.
Thanks for your support!
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Hi Richard,
I built one of your phonoclones using just matrix board and 4 x ALW superegs for the PSU. It is totally silent and sounds quite superb. So thanks for all your work in the design. However, I was wondering what possibilities there are for improvements I read this thread My take on the phonoclone which details the use of a DC servo, alternative op-amps and class A bias. Can you point me in the direction of worthwhile mods (I started going through this thread but at 400+pages its tough going)?
Thanks in advance
Ian
I built one of your phonoclones using just matrix board and 4 x ALW superegs for the PSU. It is totally silent and sounds quite superb. So thanks for all your work in the design. However, I was wondering what possibilities there are for improvements I read this thread My take on the phonoclone which details the use of a DC servo, alternative op-amps and class A bias. Can you point me in the direction of worthwhile mods (I started going through this thread but at 400+pages its tough going)?
Thanks in advance
Ian
I recently purchased a Rega Aria as the Apheta 2 did not like the 0Ω input impedance of the Phonoclone.
If anyone wants a set of fully populated PCB's, PM me. This is the PCB's ONLY not the case and PS.
I installed sockets for R1 when I was experimenting to get the unit working with the Apheta 2 and gain is set at 60db.
If anyone wants a set of fully populated PCB's, PM me. This is the PCB's ONLY not the case and PS.
I installed sockets for R1 when I was experimenting to get the unit working with the Apheta 2 and gain is set at 60db.
Attachments
@IDM The power supply and regulation matter more than the op amps, in my opinion. The coupling capacitor also makes a big difference. Finding the combination you like though can only be achieved by experimentation.
@warrjon I feel I should point out for people reading your post that those are Phonoclone 3 boards, not the Phonoclone 4 revision with the (much better sounding) S-Reg regulators.
@warrjon I feel I should point out for people reading your post that those are Phonoclone 3 boards, not the Phonoclone 4 revision with the (much better sounding) S-Reg regulators.
They still sounded excellent with my LP12/Ittok/Troika and RP8 - pre Apheta 2.
BTW they are much quieter than the Rega Aria, I am very disappointed that the Apheta 2 does not like them.
I'm not worried if no one wants them I'll hang onto them you never know I may change the Ahpeta 2 for something else
Hi
I have read through the first 100 pages of the thread or so. The main thing I have gained is that R2 can affect the sound. I had it down at 240r to work with my kontrapunkt b. I have just increased it to 490R. Gain has obviously increased which is no bad thing as the output was a little low before. I will give it a day or so before critical listening.
I agree about the psu. I have twin mono using Schottky diodes and 10000uf of smoothing. I then have 4 vbe gyrators (2 positive and 2 negative). The idea was taken from Teddy Pardo. These feed the 4 super regs, two positive and 2 negative. The result is that the phonostage is totally silent no hum or anything. Infact it’s unnerving as I keep think it’s not working until I put a record on.
Many thanks for sharing your design.
Ian
I have read through the first 100 pages of the thread or so. The main thing I have gained is that R2 can affect the sound. I had it down at 240r to work with my kontrapunkt b. I have just increased it to 490R. Gain has obviously increased which is no bad thing as the output was a little low before. I will give it a day or so before critical listening.
I agree about the psu. I have twin mono using Schottky diodes and 10000uf of smoothing. I then have 4 vbe gyrators (2 positive and 2 negative). The idea was taken from Teddy Pardo. These feed the 4 super regs, two positive and 2 negative. The result is that the phonostage is totally silent no hum or anything. Infact it’s unnerving as I keep think it’s not working until I put a record on.
Many thanks for sharing your design.
Ian
Great
I have one more doubt about caps. I've noticed you recommend Nichicon FW for C4,C5,C6 and C7 in the VSPS. Wouldn't been more appropriate the Panasonic FC for that kind of purpose? I thought the Nichicon FW were more audio grade than voltage stuff. But like I said, I'm not an expert. Just learning a little bit!
Thank you
I have one more doubt about caps. I've noticed you recommend Nichicon FW for C4,C5,C6 and C7 in the VSPS. Wouldn't been more appropriate the Panasonic FC for that kind of purpose? I thought the Nichicon FW were more audio grade than voltage stuff. But like I said, I'm not an expert. Just learning a little bit!
Thank you
The Nichicon audio series are intended for power supplies in audio gear as well as coupling use. The FG/KZ series sound better in that application than KW/FW but as a balance of size/cost I went with the latter in the VSPS.
I will not dip my toe into the "why do power supply capacitors sound different" waters as to be honest I don't really know what in the KZ design makes it so much larger, or what that might achieve.
I will not dip my toe into the "why do power supply capacitors sound different" waters as to be honest I don't really know what in the KZ design makes it so much larger, or what that might achieve.
Great! I didn't know that. I thought the Nichicon audio weren't supposed to do well with power supply stuff. That's the reason I've used Panasonic FC. That are good news since the Nichicon KA and FW series that I can get are much smaller than the Panasonic FC.
BTW, Can the RIAA resistor + cap in series be swapped between them? I've done this trick before but not sure if in this specific scenario is possible without changing the behaviour.
Thank you. I keep learning!
BTW, Can the RIAA resistor + cap in series be swapped between them? I've done this trick before but not sure if in this specific scenario is possible without changing the behaviour.
Thank you. I keep learning!
