New Express build; first time post

[Structo]

Interesting.
Sometimes we forget how important the filtering is.
Since the amp basically runs off of the caps charge it makes sense that they can play an important role in the overall sound of the amp.
I was thinking when I bought the F & T caps that they were regarded as a very high quality capacitor.
Maybe I should have gone with Sprague Atoms.

Another interesting note is that that Dumble used all 6PS polyester signal caps in his amps, but when I have researched capacitor dielectrics, polyester is the worst offender.
At least in the audiophile world.
But perhaps they had the "tone" he was after in the grand scheme of things.
Terrible temperature coefficients and dielectric absorption characteristics.
Other properties including ESR were also worse in polyester.
Teflon seem to be the best dielectric ideally but the very high cost of teflon caps put it out of reach for the guitar amp camp.

But of course, we know that guitar amps violate just about every rule for high fidelity amps since we desire them to distort at a certain point.

[WhopperPlate]

But of course, we know that guitar amps violate just about every rule for high fidelity amps since we desire them to distort at a certain point.

+1000000

[M Fowler]

I remember posting that I removed my F&T caps out of my Liverpool and presto onto a great musicial tone without all the noise I had previously.

I use mostly Illinois caps now with great results and for can caps I use JJ's.

Mark

[WhopperPlate]

Down with F&T! (sarcasm)

On another note, in redsharks express clone variations thread they talk about a 470ohm resistor to ground off of the p2v4, possibly to lower the heater voltage. Mine are around 3.35vac. I'm thinking this could possibly have something to do with my issues. Would the one resistor lower the voltage on both sides of the heaters? What value R would I need to install to lower the voltage to appropriate levels?

[WhopperPlate]

Another thought, there have been comments on out of phase preamp heater wiring (like francesca) being done for noise canceling purposes. Any credibility to these remarks? I might have to try just to see.

[Structo]

I think as long as your heaters are not above 7vac you should be ok.

[rooster]

http://www.watfordvalves.com/products.asp?id=3&man=73

OK, I for one do not think that F&Ts are bad sounding caps. The only amp I have used them in exclusively is a tweed Champ, and it sounds great - certainly as good as any vintage Champ I have played. I would hope that someone would test these in a totally stable amp before passing judgement on them. Right? I mean lets be fair in our judging process.

So if somebody here has done a recording of the same amp, set up the same way, using the same guitar, and at the same volume - but swapped out only the power caps - then I would like to hear this. ?? If the bass is so much better, for example, then the recording would show this. Till then, I don't think its really helpful to dis F&T.???

Also, where it was mentioned that the 'hiss level' was reduced by replacing the F&T caps in the power supply or on the cathode of a preamp tube , well, this is very hard for me to get behind. Hiss is not a product of a power supply or a bias cap. Now if you said a coupling stage was using an electrolytic and it generated hiss, I could easily agree with this. But here again, there's that recording option. If you can show me this with a recording I might support it.

[WhopperPlate]

Rooster, Please don't misconstrue my words; when I said "down with F&T" I was most certainly being sarcastic. I didn't think anyone here was actually "dis"ing F&T, or unfairly judging (this isn't the first time I have used F&T), rather just sharing experience. Sorry, I always forgot how easily written words can be misinterpreted. I edited my post to make things clear.

I'm sorry I didn't fully record and document my tonal experiment. By no means did I expect F&T to lose business over my assessment, nor am I trying to recruit anyone to my opinion. Again, simply sharing my observations.

These are bright amps I'm talking about (super lead and express) and the F&T's seem to exaggerate the high end, so things like HF oscillations and hiss become more apparent; not that crazy of a concept really(we're not talking wire color here). Like I said, this is just what I have perceived (and apparently others). I've happily used F&T in my 18 watt and love the sound, it just depends on the build.

I don't want to derail this thread with confusion, sorry again.

[redshark]

No need to apologize whopperplate, I think we all hear diferent, like I said before caps have a break-in time in order to sound their best, and I'm sure electrolytics can't be an exception. Think about Sozo's, diferent type of cap, everybody like the sound of them but they are notorious for their long break-in time. I have read here people insisting to leave the caps in the amp for some time before making any judgements. F&T's is what I used in my express but it has been played for almost 7 months. Not as much as I would like but probably long enough for the sound to get smoother. Whatever you decide to use I hope you can make it work.
As I said in other thread....after trying to tame the beast for 7 months...

I'm so ready to build a ROCKET!!! LOL

[M Fowler]

No different than all the kats saying Illinois caps are terrible, I ignored all thoses posts and kept right on buying them and glad I did, there great caps and cost friendly.

I have some amps still using F&T and will not change those out. We all have opinions and subjective hearing so use what you got.

Mark

[Structo]

I was reading an article about power supplies and the author recommended bypassing the last cap with a .47uF cap to remove high frequency hash.
I may have to try that. I certain don't want to fork out the $$ for Spragues if I don't want to.
Didn't they have some recent QC problems?

[WhopperPlate]

Thanks for understanding, I don't want anything I said to be taken out of context.

Neat idea Structo with the 47uf bypass. I heard the same thing about the spragues.

Redshark, my sozos definitely took awhile to break in, especially the vintage caps, but when they do the amps come alive!

The Rocket sure sounds much more relaxing, definitely going to "take it easy" with one for my next project.

I spent a lot of time desoldering and tidying up leads and wiring last night. Here's to hoping I fixed something! Cheers!

[rooster]

Yeah, I understand the intent then. I just hate to see things snowball over a comment or two. Thanks for clearing this up Whopperplate.

Structo - Hm, as to the idea of the .47 poly cap, I think you will find that this will do just the opposite of what you are thinking. Yeah, it will make the cap FASTER and that will translate to brighter, not smoother in any way. Its like building an amp with Solens caps. OW!! No not for me.

[Structo]

I tried a .1uF polyprop orange drop since that was the largest value film cap I have on hand.
Actually I paralleled two .1uF caps and connected them with test leads to the last filter cap in the PS.
Subtle difference, I though it killed the sustain a little bit so I didn't end up soldering it in.
Back to the drawing board.

[ChrisM]

I would have tried it on the first filter cap, would have more affect there.