Listening tests of high end capacitors...

[Lovelock]

This summer I had a holiday (shop = closed) for 3 weeks. As I was also finishing a relic tele I decided to have some fun and wind my own "boutique" paper in wax cap for just this project. Tried different foils (aluminium, tin, copper) and different papers (see tru kraft, baking paper & others) I wound a whole bunch of caps (about one hundred) & documented the procedures & resulting values. Documenting values before and after baking them to get rid of residual moisture & potting them in a Fralin style pickup potting wax mixture made a great difference!.

I also compared the home made caps with my regular vishay/sprague polyprop orange drops & collection of tropical fish style caps & wima's.

While making capacitors I got better at it, and was able to predict values and determine the most reliable construction method. I had read a lot about unreliabability in paper in wax caps on valve/tube radio forums, but hey, these guitar caps don't get large voltages! Yes these new home made caps where here to stay!

After installing my most reliable cap & best value for the guitar the whole project was intended for, it sounded great, until after about a month it shorted out! =Oops, expensive luthier relic tele with two volume controls! Luckily I hadn't sold it yet, and it was still in my shop!

I rewired the guitar with a regular polypropylene film type cap and it sounded just as good, and now, for the first time I actually dare to sell this guitar to a performing musician, who might actually need his tone control on stage..
Lesson learned.

It might sound like I am a sceptic, but devoting 3 weeks to experiment with manufacturing caps, and also trying all sorts, it may also seem I am an insane believer of mojo. However I dare conclude the following:
1: The sonic improvement of a boutique cap is by no means as important as the reliability of this given cap.
2: I found the real difference in sound between different (foil) caps quite marginal at best.

[David Schwab]

1: The sonic improvement of a boutique cap is by no means as important as the reliability of this given cap.

And when you realize there is no sonic improvement, it's all smoke and mirrors!

Thanks for sharing the story. That had to be a little fun making caps.

[Lovelock]

It certaintly was fun, but could have made a nice neck & body in the same time. I did learn however, how to make an unreliable paper in wax mojocap of a given value..
It reminds me that being able to buy the exact aged 1% Mallory mica silver sprague cap online, cost me the 3 other electronic parts shops I had nearby in the last 10 years. Only have one local parts shop left now, and it's not my favourite, but: Great to have them close by, as they always seem to stock the right value "run of the mill cap" I need for the artist in need that has a show tonight..

Dreaming: If only they stocked all top quality components in all values known and where open 24-7..

[David Schwab]

No need to worry about running out.

[12Bass]

Related thread which may be of interest: Eden Electronics Forum - Tone Capacitors and your Passive Bass Guitar

[Chuck H]

BwaaaaHahahahaaaaaa (gasp) Hooooohohohahahaheheheeeee.

[Steve Conner]

My JB sounded like a GRAND PIANO with this in it. (~$11 each)

OMG... Must run out and buy one...

Also, re the discussion on PCBs above: I don't see any reason why a PCB-made amp shouldn't be boutique quality and repairable after 50 years. There are 50 year old transistor radios built on PCBs, and those are perfectly repairable now.

As other people said, use good quality fiberglass PCB, generously-sized traces so you can replace the components several times before they wreck, avoid SMDs like the plague, and I would probably use chassis-mounting tube sockets and pots, connected to the PCB with flying leads. That would add a fair amount of labour cost to the build, though.

I said to avoid SMDs, but will through-hole components still even be available in another 50 years? Will they still make tubes? Maybe if I wanted to build a real quality amp to last 50 years, it would have to be solid-state. That's one thing I like about bassists over guitarists: they're open-minded enough that they'd pay boutique prices for something with no tubes.

[Alex R]

I want some of those booty-shaking lows.

[Alex R]

My lows are just not booty-shaking enough right now. Anyhow not enough to shake a really massive booty.

I want to thank that poster for doing more to enrich my word power than the Reader's Digest ever did. All these adjectives in just one post:

Massive
Booty-shaking
Profound
Modern
Warm
Earthy
Punchy
Organic
Flat (those disappointing little ceramics)
and... "yep that's the tone"

If I'm a bit short on "vintage warmth, organic, and versatility" I will know where to go. How glad I am not to be the kind of "player that plays with 1 tone" who is satisfied with cheap nasty insensitive untalented little ceramic discs.

[Mark Hammer]

Also, re the discussion on PCBs above: I don't see any reason why a PCB-made amp shouldn't be boutique quality and repairable after 50 years. There are 50 year old transistor radios built on PCBs, and those are perfectly repairable now.

As other people said, use good quality fiberglass PCB, generously-sized traces so you can replace the components several times before they wreck, avoid SMDs like the plague, and I would probably use chassis-mounting tube sockets and pots, connected to the PCB with flying leads. That would add a fair amount of labour cost to the build, though.

I said to avoid SMDs, but will through-hole components still even be available in another 50 years? Will they still make tubes? Maybe if I wanted to build a real quality amp to last 50 years, it would have to be solid-state. That's one thing I like about bassists over guitarists: they're open-minded enough that they'd pay boutique prices for something with no tubes.

As I keep reminding those around me at work, just because something is treated as a "best practice" in one context does not mean it will necessarily be a best, or even commendable, practice in another. It's not use of PCBs that is to be avoided, it is use of PCB qualities and techniques that were developed and tailored to low temperature/voltage contexts.

[Alex R]

I'm really not an expert having never been involved with PCB-making either at manufacturing or hobbyist level. But (I mm-might have mentioned this before) the PCB in the Chinese-made low-priced Epiphone Blues Custom 30 looks good to me - thick material, wide traces with room between them, etc. I'd be fascinated to hear an expert opinion on that PCB. As a simple repairman, my reaction on opening it up was, wow, that's a well-built amp.

Boy is that off-topic! Erm, the board has caps on it...

[David Schwab]

I want some of those booty-shaking lows.

Then learn to play bass. All the booty shaking lows you would ever want.

Otherwise turn the damn low end down on the guitar amp! Guitar players often clog up all the free audio space with too much low end. That might sound fine soloed, but not with a band.

[Chuck H]

+++

I design so that my amps have appropriate bottom end for guitar, plus a bit.

Sometime when I'm playing "solo" I do want more bottom end. But when I presented at winter '09 NAMM it seemed like every guitar amp was pushing sooo much bass that mine couldn't compare. Every player was doing the bedroom version of "metal" or "jazz" with all the bass end audio space used up. It was really telling for me. I need to design amps for ego's not players. The best recorded guitar tracks (as public opinion recognizes) aren't that bass heavy at all. But it seems to be what players want. So my choices are to either build a good sounding amp OR build what players seem to want. And the two seem mutually exclusive. Sigh.

[Steve Conner]

Or, make an amp with the POTENTIAL to push lots of bass, but a bass knob to regulate it.

That way the player can do his woofy drone thing, and when he finally grows up and realises that it's pointless in a band situation, he can turn the bass down and the midrange up. Suddenly it sounds fantastic, cuts through the mix beautifully, he has one of those "Aha" moments, and he doesn't even need to buy another amp, he has one that can grow with him...

Ugh, how new-agey, but I think it's a valid point. Why should an amp have only one good tone in it? If you have a big, powerful power amp and a hefty speaker in a closed cabinet, you can use that to make thumping bass at practice volume, or lots of midrange SPL to rip people's heads off at a gig.

You hear a lot of metal tracks that have thunderous, bass-heavy riffing, but that's probably the bassist doubling the guitar riff. If you could hear the rhythm guitar on its own, it might not be that bassy.

PS: Leo Fender himself invented the mid scoop. Magnetic pickups boost the midrange, and that's what makes an electric guitar sound "electric". Its natural tone is more like a horn than a guitar. His tonestack boosted the lows and highs to compensate: he was trying to make it sound like an acoustic guitar again.

[David Schwab]

You hear a lot of metal tracks that have thunderous, bass-heavy riffing, but that's probably the bassist doubling the guitar riff.

Unless it's Metallica, in which case you never hear the bass. (unless it's old Metallica)