Calrec EQ resistor choices?

[unqlenol]

Hi folks,

Long time lurker, first time poster and, I'm afraid, a pretty Noob DIYer.

I am trying to build a Calrec EQ, 2 channels and I have hit my first question:

Do I need to be concerned that some of my resistors are Carbon Film as opposed to Metal Film?

The BOM did not specify MF or CF  and I never thought about it. The components supplier has supplied some resistors as MF and some as CF. I know I have read that metal film is generally the better choice for audio signals. Do I need to be worried about the Carbon Film resistors?

Thanks in advance for any help.

Best,

Nolan

 

[plumsolly]

No. You do not. If someone tells you resistors sound different (with the exception of how noisy they can be), slowly back away.

Best,

Ben

 

[unqlenol]

Many thanks, Ben.  I like that kind of approach. Otherwise I'll spend my whole life fussing too much. 

But hold on...:

What about these things I read about Carbon Film Resistors changing over time  and being influenced by heat and humidity?  Do any practical folk care about this? If this is true, does using CF resistors reduce my chances of trying to make a very roughly 'stereo matched' pair of channels?  I am trying to measure and match resistors for each position on each of the respective PCB's for the two channels. So  I am also concerned that CF resistors may suffer greater fluctuations in performance over time, thus potentially sabotaging my attempts at a basic stereo match.

Is this thought process and concern over CF resistors also in the realm of 'not worth fussing over'?

Thanks again.

Nolan

PS: I realise that my pursuit of a stereo match may be naive in the first palece given my limited knowledge.

 

[plumsolly]

There are a number of reasons for you not to worry about this, but at the top of that list is the fact 1% metal film resistors are cheap (~.10$ in small quantities in the U.S.).  This is what I use for most things. Where are you located?

Best,

Ben

 

[unqlenol]

Hi Ben,

Thanks very much, Ben, for taking the time...

To clarify, I am not worried about spending the money on a new batch of resistors. I am in South Africa and the cost is negligible. I am trying to work out whether it is worth the time and effort of re-ordering or sourcing MF resistors elsewhere as about 75% of the resistors I ordered were Carbon Film. I have no idea why the supplier gave some as MF and some as CF. I will ask them. 

If they can give me all as MF, I will/can make the order. I did however want to check in here to see if the effort is worth the fuss...

What I am getting from you is that any difference in sound is negligible, but you generally stick with MF....right?

Thanks again,

Best,

Nolan

 

[hymentoptera]

...

But hold on...:

What about these things I read about Carbon Film Resistors changing over time  and being influenced by heat and humidity?

...

You might be thinking of carbon composition. They're the older style, bigger, brown, cylindrical things, mostly associated with tube amps these days. They were pretty much completely phased out in the early 1970's.

Agreed with the comments above, metal films are cheap enough now that there's little reason to bother with carbon film, but if you do get struck with them, well there's tons of great gear out there that used nothing but, so they can't be all that bad

 

[unqlenol]

Thanks , Hymentoptera.

I had read that Carbon Film (not 'Composition') resistors can have *slightly* fluctuating properties over time. But your point is well taken and I now know not to worry too much if I end up needing to use them.

So thanks to all for the help!

Best,

Nolan