Advice on best resistor and capacitor brands?

[Ken Moon]

Keith is that your Talon 30 amp? Nice looking layout.

Mark

yep. that was the only one I've built with a single turret board - it's more of a heavy metal amp than most of my Talons, designed specifically to not poop out in Drop-C tuning.

I'm hoping to finish a 50W design by Christmas - should be interesting

[ToneMerc]

Ken, I noticed that you are using what looks like Mojo Vitamin T PIO caps. What do u think of them? I'm using the same Brazil based PIO cap (branded as MOD )in a couple of SE harp amp builds.

Also, I've had a couple of 5.6uf Solens for awhile. At what location would you recommend using them?

Mike

[JamesHealey]

Vishay mkt1813 for coupling
Vishay bc components for electrolytics
Cde silver Mica
Multicomp carbon films
And what ever metal oxide for power

All available at farnell which is just on my door step.

[Cliff Schecht]

My tip of the week to folks is don't write off good quality Tantalum caps as a replacement for low uF value electrolytics in cathode bypass applications.

Tants explode when subjected to over-voltage. Not the kind of caps I use in MI applications...

Some elcos are really good for bypass or even coupling apps, check for instance the Nichicon Muse ES BP series (OK, they are radials).

Try connecting a 35V electrolytic to 450V. Molten metal, smoke and lots of powder. Whats the difference?
Some of the guys on this board regularly use ancient NOS electrolytics. Now thats dicing with a potential explosion.
The Tants I use fail by splitting in half when subjected to extremely high voltages. Known fail states of internal components are critical for compliance in some markets.
Like everything there are many different types, qualities and ratings.

Using NOS electrolytics isn't dangerous if you know how to test them properly. I've never had an old electrolytic go bad on me after I tested it and verified it safe.

[FYL]

Try connecting a 35V electrolytic to 450V. Molten metal, smoke and lots of powder. Whats the difference?

Well, subject a 25 V-rated generic tant to 30 V, then to 35 V, and see what happens...

Some of the guys on this board regularly use ancient NOS electrolytics.

NOS 'lytics can be fine if properly tested and reformed. Even new caps should be tested and formed before being used.

The Tants I use fail by splitting in half when subjected to extremely high voltages.

That's how well behaved high end gel tants should fail. But el cheapo models using liquid electrolyte just burst/explode. And applying say, 2 V reverse voltage leads to the same messy result.

Known fail states of internal components are critical for compliance in some markets.
Like everything there are many different types, qualities and ratings.

Agreed.

['67_Plexi]

Tants explode when subjected to over-voltage. Not the kind of caps I use in MI applications...

Some elcos are really good for bypass or even coupling apps, check for instance the Nichicon Muse ES BP series (OK, they are radials).

Try connecting a 35V electrolytic to 450V. Molten metal, smoke and lots of powder. Whats the difference?
Some of the guys on this board regularly use ancient NOS electrolytics. Now thats dicing with a potential explosion.
The Tants I use fail by splitting in half when subjected to extremely high voltages. Known fail states of internal components are critical for compliance in some markets.
Like everything there are many different types, qualities and ratings.

Using NOS electrolytics isn't dangerous if you know how to test them properly. I've never had an old electrolytic go bad on me after I tested it and verified it safe.

That can be true or you are lucky. I'm sure you must have witnessed an exploded cap or had one do a dump on the chassis ?
Anyway, I would assume far fewer hobbyists especially newbies test them or have the equipment to test and reform them than those that will just put them in and flip the switch.

In new equipment sold to the public the accepted shelf life of a dry cap would not normally exceed 3 years . After 5 to 10 years the oxide layer becomes pretty depleted and even if you reform them they will not meet the original ratings.

Bottom line reformed NOS caps are not be as effective as a new cap. of the same value or of a cap thats the same age thats been used regularly.

So apart from aesthetic reasons, I ca't think of a single compelling reason to use them over a new cap and it's certainly not something I would recommend to a beginner.

Paper/Oil caps. are even worse. The way they are all stored also affects their life too. Airtight bag in a warm dry environment will be much better than sitting in a box in a garage.

['67_Plexi]

Try connecting a 35V electrolytic to 450V. Molten metal, smoke and lots of powder. Whats the difference?

Well, subject a 25 V-rated generic tant to 30 V, then to 35 V, and see what happens...

Some of the guys on this board regularly use ancient NOS electrolytics.

NOS 'lytics can be fine if properly tested and reformed. Even new caps should be tested and formed before being used.

The Tants I use fail by splitting in half when subjected to extremely high voltages.

That's how well behaved high end gel tants should fail. But el cheapo models using liquid electrolyte just burst/explode. And applying say, 2 V reverse voltage leads to the same messy result.

Known fail states of internal components are critical for compliance in some markets.
Like everything there are many different types, qualities and ratings.

Agreed.

Totally agreed.

[Ken Moon]

Ken, I noticed that you are using what looks like Mojo Vitamin T PIO caps. What do u think of them? I'm using the same Brazil based PIO cap (branded as MOD )in a couple of SE harp amp builds.

Also, I've had a couple of 5.6uf Solens for awhile. At what location would you recommend using them?

Mike

They sound very nice for coupling caps between the PI and PA - I really didn't notice any difference at all in the .1uF PI cap.

I hate to try to describe tone with words, but when I test components, I mount the components on micro-alligator clips that pop right into the top of the hollow turrets (tight enough that you don't need to solder them to do the test), and have someone else switch back and forth while I play.

I did get one new one that was shorted, but Mojo was very nice and sent me 10 more good ones for free. I'll still use Mallory 150s in that position if I don't have the Vitamin T's on hand.

I only use the Solens for filter caps. If you have any RC filter stages where the dropping resistor is 10k or higher, and the original filter caps are under 50uF, you could sub those caps you have, just to see if they do anything you like.

I do use a 4.7uF Solen for the reservoir cap (I've gone as low as 3.3uF), but I can do that because I use a CLCLC filter, and there are two stages of filtering before the plates.

[Ken Moon]

Vishay mkt1813 for coupling
Vishay bc components for electrolytics
Cde silver Mica
Multicomp carbon films
And what ever metal oxide for power

All available at farnell which is just on my door step.

I'm jealous.

I love those blue Vishay BC electrolytics, but the only place I can find them here is at Newark, which I think is the same company as Farnell, and they charge a $20 surcharge per order for BC stuff from the UK

[Richie]

mouser has them.. also try digikey.

http://www.mouser.com/search/refine.asp ... =122163669

or a better price these BC
http://www.mouser.com/ProductDetail/Vis ... WUteIxg%3d


digikey has them too search capacitor, then filter vishey/bc componets

[Ken Moon]

You had me excited for a second, especially when I saw "new at Mouser" on the Vishay BC caps, but it looks like they don't have the 041-043 ASH series, which is their 450V long-life series (I still think the Nichicon PW series is superior due to its 105 degree rating, but these are the best axial caps I've found):



http://www.vishay.com/docs/28329/041043as.pdf

The popular 47uF/450V is part number MAL204317479E3, and neither Mouser or Digi-Key carry it (or Allied).

Here it is at Newark:

http://www.newark.com/vishay-bc-compone ... dp/98K6713

I've used the 138 AML series for cathode bypass caps, but they only go up to 100V.

Am I not looking in the right place?

[daydreamer]

I've built about 2 dozen p1-eXtremes, using several different layouts and various component types and brands, and they all sound about the same - it's a nice clean-to-classic-rock amp that takes pedals well.

I guess that would be the EL34 making it bright?
It was the thorough documents and entire forum dedicated to it that has lead me that way, not so much sound reviews.

It seems to be a forgiving design, component wise, if they are all similar sounding then.

I would like to make a test bed for tubes eventually, I.e what each type/ brand sounds like, build an audio library for reference. (that's one of the design challenges i have set myself to learn.) It's actually a relief to hear that the other components aren't swinging the sound vastly in this design.

I'm also following the NOS tube thread closely, great stuff!.

BTW I hope everyone has seen the videos of the french guy making old radio tubes by hand,

http://www.youtube.com/watch?v=gl-QMuUQhVM

thanks

Andy[/quote]

[Ken Moon]

Hey Andy,

That P1-eX is a very good test bed, if you have the variable bias pot.

I call mine 'the tube tester'.

All of the AX84 amps are on the bright side. I think it's just the preference of the guys who designed them, but side-by-side with any of my other amps, both the P1 and the p1-eX sound bright. But that's why there's a Treble knob - I usually keep my Treble at about 10 o'clock on the P1-eX.

[JamesHealey]

Yeah ken i just tried them as a once off cause i didn't fancy mail ordering f&t any more. And they sounded fantastic so I've never gone back. I just wish they did 6ps, mallory 150 or 225p at farnell cause the mkt1813 isn't the best sounding cap a bit bright!

Vishay mkt1813 for coupling
Vishay bc components for electrolytics
Cde silver Mica
Multicomp carbon films
And what ever metal oxide for power

All available at farnell which is just on my door step.

I'm jealous.

I love those blue Vishay BC electrolytics, but the only place I can find them here is at Newark, which I think is the same company as Farnell, and they charge a $20 surcharge per order for BC stuff from the UK

[Structo]

I always like to post this picture when I hear of guys using old caps or not replacing one that is old.

This is in a JTM 45 and is the original cap.
The owner said that he had planned on replacing the caps but put it off because the amp sounded glorious.

What a mess, the electrolyte paste is all over the interior of the chassis.

If you do insist on using NOS caps, be sure to warm them then reform them slowly.