News:

Hi!

Welcome to my DIY audio forum.

Cheers
Per-Anders Sjöström

Main Menu

Critical transistors in QSXM2

Started by fantast, January 06, 2012, 09:30:49 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

fantast

Well, not critical, but to have an eye at.
What do you think are the most important, where I need to use 1% metal film; R48 (I assume); R2 and R50 (I expect) and maybe R16/17 and R42/43?

For the RIAA the 2M7 might be the most critical one?

Kind regards
Claus

peranders

I think you should use metal film everywhere. The feedback resistors are the most sensitive I should think.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

fantast


peranders

I'm out in the bush so you must enlighten me. Where is the R35 in the design?
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

peranders

I'm back from the bush...  :-)

R34, R35 is not critical when it comes to tolerance. You could use other types there.
/Per-Anders Sjöström, owner of this forum

Homepage with my DIY hifi stuff

fantast

Hi P-A,

thanks. Thought about it and got to similar conclusions.

Besides: Thanks for that great sounding prepre. I use it now with my JA and a Jensen Step-Up (selfmade from JT 347). The step-up is to keep my nerves calme; the JA will be cooked quite easily by any DC which goes back into the cardridge :|).
Togetherwith the step-up it's a great combination and I feel it is much clearer, more extended and faster than my Schönhut pre, that I used before.

Today I changed R93 (OK, I soldered some tulip pins in there as basis for putting in various resistors to test; wheras R93 is quite not a favorable position for such things :|).
I put it to 56k and connected the stage directly to my power amp (MX 10000) and it seems to work better than with the preamp in between (does not come as a surprise :?)

But I doubt if the prepre will be able to drive my full bi amp configuration (I did not connect the bass now..)

Do you think it can?

Many regards
Claus

PS: Will try to integrate some THAT300p shortly