Simplistic NJFET RIAA

Member
Joined 2006
Paid Member
Some pros use severall smaller caps in parallel so they can reach good tolerances during production.

As a DIYer I do not have access to expensive measuring equipment so I will welcome any tip about a better method for measuring acurately the resistor and caps values.
 
Tolerances for teflon RIAA caps

Hello chaps-

Still s-l-o-w-l-y working on my 2nd Salas jfet RIAA...!

Good timing on this tolerance talk. I sent an email requesting some teflon caps from Marko at 33audio. The link to his web store was posted here a few times. He got back to me with some matching results.

Marko's selection of 47 & 15 nF caps is getting thin. He was able to get a 'fairly' close set for me-

47nF "J" Tol, 200V, Custom TFHT 1.2 x .55----
.0471 uF, .0473 uF

15nF "F" Tol, 200V, TexCap 43 .87 x .32----
.01501 uF, .01503 uF

Apparently he has "a $200 hand-held DVM" and "some CRC 1/4-percent caps that I use for reference".

As he's been testing/selling for a while, I am assuming his results are somewhat accurate.

The 15nF's look OK, but the 47nF's might be a problem. At $15/cap, I'd rather get something lower in value to trim up. Anyone here cross-checked his results?

Cheers- Kent
 
Member
Joined 2009
Paid Member
Hey guys,

I measured my new cart without the body & without 4 Cardas screws that I must be removed because can fit correctly the cart with them so I used ultra small headshell leads, I calculate the moded cart weight:

-1.566gr body cart
-0.856gr 4 Cardas headshell leds
+0.282gr 4 new headshell leads

Total moded cart lost 2.14gr, now I understand that can get the same sound, 1st I believe was that RIAA needs a new adjust but isn't the RIAA the real reason it's the cart lost 2.14gr & that's decrease the effective mass of the combo tonearm+cart:mad:

Now I'm looking how to add these 2.14gr because the sounds is very very different, of course I prefer with 2.14gr more;)
 

Attachments

  • DSC00069.jpg
    DSC00069.jpg
    394 KB · Views: 343
  • DSC00070.jpg
    DSC00070.jpg
    451.3 KB · Views: 339
  • DSC00071.jpg
    DSC00071.jpg
    454.4 KB · Views: 330
Member
Joined 2009
Paid Member
Hello chaps-

Still s-l-o-w-l-y working on my 2nd Salas jfet RIAA...!

Good timing on this tolerance talk. I sent an email requesting some teflon caps from Marko at 33audio. The link to his web store was posted here a few times. He got back to me with some matching results.

Marko's selection of 47 & 15 nF caps is getting thin. He was able to get a 'fairly' close set for me-

47nF "J" Tol, 200V, Custom TFHT 1.2 x .55----
.0471 uF, .0473 uF

15nF "F" Tol, 200V, TexCap 43 .87 x .32----
.01501 uF, .01503 uF

Apparently he has "a $200 hand-held DVM" and "some CRC 1/4-percent caps that I use for reference".

As he's been testing/selling for a while, I am assuming his results are somewhat accurate.

The 15nF's look OK, but the 47nF's might be a problem. At $15/cap, I'd rather get something lower in value to trim up. Anyone here cross-checked his results?

Cheers- Kent

My caps where measured OK by Mark when I checked with my LCR.
 

Attachments

  • DSC00072.jpg
    DSC00072.jpg
    518.3 KB · Views: 332
Member
Joined 2009
Paid Member
Hi Merlin, last week I've disassemble my damaged ortofon MC-X5, I have found 2 pieces of lead in the housing, small one right at front (behind label), the bigger one near head shell, I guess you can add weight, but where and how many exactly? I don't know :)

I tried with a small piece of lead (2.14gr) fixed with blu-tac, see pic.
 

Attachments

  • DSC00074.jpg
    DSC00074.jpg
    524.4 KB · Views: 278
Member
Joined 2006
Paid Member
I added some mass to the headshell of the RB300 I am using with my DL103 and it works wonderfully.

I agree with you that the DL103 needs some mass to show it´s true character.

My friend Luis Pires (the man behind the Benz LP) kept telling me the benefits of using a high mass body for the MC carts. He personally chose the special African Wood used in the LP.

Maybe it would be a good idea to build a good wood body for the DL103..... :)