IRC 0.1% metal films in a Aleph 1.7 preamp?

[darkmoebius]

Has anyone tried IRC's precision resistors in signal, feedback, or gain sections of an amp?

I'm assuming that the 0.1% tolerence would be good in a fully balanced circuit, but what about the sonics?

The price doesn't seem too bad($30-40 for everything), so I was thinking of using these everywhere and then slowly swapping in better resistors for each specific section if need be.

[kilowattski]

Dark,

I got your emails and will send you a spreadsheet of all the parts I used, their cost and where to order from. I will send it to you torrorrow. To answer your question, if they are metal film they will be ok. Wirewound resistors are not a good choice IMHO. I used Holco H8 resistors from Parts Connection.

[illusionxx]

kilowattski,

am i right assuming that the spreadsheet is about the parts you used in your Aleph P? If that`s the case, could you please send me the spreadsheet too(Forum E-Mail is enabled)? Im going to start gathering the parts for my Aleph P in january and i think this would be a great help.

Thx, illusionxx.

[kilowattski]

No problem. I don't know if I can attach a file to an email sent from the forum. Why not send me an email with your email address so I can use outlook.

[darkmoebius]

Originally posted by kilowattski
Dark,I got your emails and will send you a spreadsheet of all the parts I used, their cost and where to order from. I will send it to you torrorrow. To answer your question, if they are metal film they will be ok. Wirewound resistors are not a good choice IMHO. I used Holco H8 resistors from Parts Connection.

Thanks for the help, I definetly can use it.

The only thing that was making second-guess the Holco's was posts that I had read around here saying that the quality of that brand had changed drastically in the last few years. Mainly that they were no longer non-inductive or non-magnetic. But, it still seems that a lot of people are using them with terrific results.

So, I was simply wondering if the tighter tolerence IRC's might be better.

But, I think it would be best for me to go with parts that are known to work well first and then experiment later. Your Aleph turned out great , so I'll follow your lead.

Can't wait to order up everything, I've got a new TDA1541A parallel dac kit from another thread on DiyAudio that is dying for a preamp up to it's caliber. The same goes for the "Zeus" amp I'm building.

[kilowattski]

I can tell you for sure that they are both Non-Inductive and Non Magnetic. Holco is still used by quite a few high end companies for both attenuators and general audio circuitry. After looking at the IRC specs, they are not bad either. As a matter of fact the IRC's look pretty good. If you can get a good deal on them, use them. There would be no reason to change.

[darkmoebius]

I thought I would be the only person lurking about here today.

Originally posted by kilowattski
I can tell you for sure that they are both Non-Inductive and Non Magnetic.

That was my big worry because IRC's spec sheet doesn't specifically say that.

Holco is still used by quite a few high end companies for both attenuators and general audio circuitry.

That's why I was leaning towards Holco. There are a lot of companies and DIY'ers that have gotten excellent results with them. I can only find a couple of posts regarding IRC's and they were mostly used in one or two specific places - never throughout an amp or signal path.

After looking at the IRC specs, they are not bad either. As a matter of fact the IRC's look pretty good. If you can get a good deal on them, use them. There would be no reason to change.

Mouser carries the 0.1% metal films for >$1 ea. Sounds expensive, but that's really >$35 for the whole preamp.

Then again, Parts Connexion has Holco's for 1/2 that. Perhaps, I'll get both and swap parts in different positions to see if it makes a difference.

[darkmoebius]

Originally posted by darkmoebius
Mouser carries the 0.1% metal films for >$1 ea. Sounds expensive, but that's really >$35 for the whole preamp.

Whoops, I meant <$1 ea. and <$35 for the whole preamp.