The Phonoclone and VSPS PCB Help Desk

[rjm]

Originally Posted by kor952

The sound difference between PC one with X-reg and PC two with 78/7912 supply both with the same 50VA 12+12V Triad toroid was very small.

Get rid of the regulators. The X-reg, which is on board, is all you need. Send the rectified, unfiltered voltage to the boards directly. Then, redo all your tests.

[kor952]

Originally Posted by rjm

Get rid of the regulators. The X-reg, which is on board, is all you need. Send the rectified, unfiltered voltage to the boards directly. Then, redo all your tests.

Maybe i was not clear or i misunderstood your answer but I disabled X-reg on the second Phonoclone because I wanted to hear the difference between X-reg and 78/79xx regulation. So the 78/79xx are not in front of the X-reg.

@ Dimkasta, I removed the Mystic Mat and lowered the arm, first impression is that it solved the problem but for real critical listning I have to wait till it's after 0.00 o'clock then there will be much less distrurbing surrounding sound.

[dimkasta]

VTA is a usual suspect when it comes to harshness. Just make sure that you did not lower it too much because your bass will suffer (will sound fuller but muddy if you go too low)

[kor952]

I am back at my original VTA and also the Mystic Mat is on the platter again. PC1 sounds realy mellow now. I am sure the harshness had to do with breaking in. I had to extend the PC1s supply wires to the outside of the case cause I could not implement a second XLR-inlet on the case for the second PSU. I think these extension wires needed a break in, can't think of anything else except for the ground wires, wich are the only wires connecting the left and right channel.
Further on I started to read this thread at page one, after reading the first 50 pages I got the impression I was reinventing the wheel with my tests as described above.....many of my findings were already written in the first 50 pages. Such as 12V supply sounds better as 15 V and ...... OPA627 sounds softer as OP27G.

Ronald.

[woodturner-fran]

Very interesting to hear your thoughts Ronald. Yes, there are many good ideas in the thread - its hard to find the info some times. I think the special "kit" offered by rjm prior to the x-reg is an excellent summary of the best parts for each position.

I have long wondered about a dual rail supply, fantastic to hear impressions from both side by side.

Fran

[dimkasta]

Damn... you both made me start reading again...

Ronald, about the second XLR socket, you can use a 6pin one. I just received mine to keep the psu cable a single one. Now I just have to find some nice 7wire olflex...

[kor952]

Originally Posted by dimkasta

Damn... you both made me start reading again...

Ronald, about the second XLR socket, you can use a 6pin one. I just received mine to keep the psu cable a single one. Now I just have to find some nice 7wire olflex...

Yes i realized that but I did not want to wait with testing, now i have two 3-p XLR male connectors dangling outside the case.....

It is a nice read (but lenghty) how the Phonoclone did devellop till what it is today.

Ronald.

[woodturner-fran]

There's 2 threads too!


Fran

[rjm]

Originally Posted by dimkasta

Now I just have to find some nice 7wire olflex...

That's where I always get stuck! I found it easier to just have two 3 pin XLRs, and use regular 3-wire power cord...

[rjm]

Originally Posted by kor952

I am back at my original VTA and also the Mystic Mat is on the platter again. PC1 sounds realy mellow now. I am sure the harshness had to do with breaking in. I had to extend the PC1s supply wires to the outside of the case cause I could not implement a second XLR-inlet on the case for the second PSU. I think these extension wires needed a break in, can't think of anything else except for the ground wires, wich are the only wires connecting the left and right channel.

Trying to do precision evaluations like this with vinyl is tough, but it does give you that extra dimension of flexibility: cartridge alignment can compensate for, or be adjusted with reference to, the phono preamplifier.

I'd have to doubt the break in of the wires as being the culprit here, but remember the coupling caps break in with hours played, not hours powered up, and need at least 100 of the former.