NOS caps vs New caps

[calis]

Hi guys.

I kinda browsed things over and did some searches but I wasn't really able to find the answer to this question. If this has already been discussed ('cause it seems like it should have been), I apologize in advance and please just point me in the direction of that/those thread(s).

I am planning my second amp build. My first build was a Tweed Champ (5F1) clone. I purchased a kit from Ceriatone to do that build. That was a pretty easy build and I ran into no real troubles along the way. For my second build, I'm planning a Tweed Deluxe (5E3). This time, I don't wanna use a kit. I'm planning to use this schematic:

http://www.ampwares.com/schematics/deluxe_5e3.pdf

And I'll just collect the parts myself. I've read a little bit about NOS caps and I wonder how necessary they are. Do I really need to get NOS caps to build a good Tweed Deluxe? Or can I just go to someplace like hoffmanamps.com and just buy new caps from there? Please let me know what you guys think.

Thanks very much.

Justin

[Mandopicker]

Using NOS caps...why not just drift the parts values?

I my opinion, using NOS caps is a dice roll. After a certain number of years, even on the shelf, caps can and do dry out.

Here is something worth discussing...

If you are trying to get the best vintage tone possible and are fortunate enough to know someone with a really great sounding vintage amp, is it possible that one could measure each part...and by using those drifted values (common in old amps) in a new build, get closer to a vintage tone
as opposed to going the NOS path from the beginning?

Could this get you in the ball park of the tone of a vintage amp - but with all new parts? (not talking about the further impact of NOS transformers or tubes)

After all...most old amps sound great because of how the parts have drifted...or settled in opver time.

Just my 2 cents.

[calis]

Thanks, Mandopicker, for your very good reply.

So, in short, if I want to end up with something similar to what a brand new Fender Deluxe would have sounded like in 1956, then using new caps (bought from an electronics supplier) will get me pretty close. However, if I wanna get closer to the sound of how a well-cared-for 1956 Deluxe sounds today, then I could find caps with similar values to those of the drifted values of the old caps in that amp. Right? Feel free to correct me if I misinterpreted your response.

That poses a new question if you don't mind. If I use new modern caps in my 5E3 build, will they drift like the caps put into amplifiers that were built in the 50s?

Thanks again. This is a big help to me.

[soundmasterg]

Going NOS for coupling caps is ok if the caps are polyester, polypropylene, mylar, etc. Essentially plastic caps are ok.

If they are paper, electrolytic, ceramic....it is not a good idea to use them.

New cap manufacture is much closer tolerance these days than 40 years ago, so newer caps will not drift as much as older caps.

If you had an original amp that sounded cool with drifted caps, you could measure each resistor and cap and recreate that somewhat with newer caps, but the hard part of this is that caps are made in standard values and you would have trouble finding in between values.

Greg

[calis]

Thank you for your response, soundmasterg.

I think that pretty much covers what I was hoping to learn. I really appreciate you guys taking the time to offer your advice. Thank you again.

[Mandopicker]

Glad I could help.

Remember...never pass up a chance to take a vintage amp home for some playing enjoyment and indepth investigation.

Be sure the owner is cool with the idea and could gain value from the experiment as well.

* Measure what you can and take note of any other peculiarities that may play a role in creating the tone of the amp. Assuming you like it.

Have fun!

[stokes]

Stay away from NOS electrolytics.They dry out sitting on a shelf with no voltage applied and should not be used.

[calis]

Okay. That is good to know. Thank you, stokes.

[cminor9]

Aren't most modern electrolytics still about 10/20% tolerance? The ones I have seen are. I'd say you'll still get a lot of variation among new ones.