vintageHIWATTconvention.com

They are bulging like this:

Hello, my name is Biagio and I am italian.
I have several Hywatt amps and I see that caps have problems like this one.
I am trying to find some new caps for my babies, but it looks soooooo hard!
I'd like to find some Mundorf or RS (the first ones look to be the best, the second ones are Hywatt's first choice), but I am not able to do that...
Is there anyone who can tell me where I can find those items?
Thank you very much.
Brainstorm

Hi Biagio,

I don't think that RS makes this type anymore.

Being in Italy, you should have access to F&T from Germany or TAD marketed by Tube Amp Doctor.

Good Luck!

Thanks for your answer.
I'll try and find them and will let you know...
Bye.

Gad zooks! Now those caps are BULGING!

Mike

Mike B. wrote:Gad zooks! Now those caps are BULGING!

They must be from Czechoslovakia... trying to "swing successfully."

mikhailwatt wrote:

Mike B. wrote:Gad zooks! Now those caps are BULGING!

They must be from Czechoslovakia... trying to "swing successfully."

Heh, good one! I am digging this place. Mucho to learn!

hello all

so I just got my new to me 1974 DR-103 and with the exception to a couple of tubes it all original. the caps do look like the above listed ones. should I not even play the amp till I get it repaired? i went to VHR and saw the cap kits and there are 3 different ones which one is the one for my head? is there anything else i should look into changing on it? played it for 15 Minutes and it sounded amazing and quiet with little to none of tube noise. any help you guys could offer would be greatly appreciated.

thanks,
Bill Z

here are some pics for your viewing pleasure

Nice Rig!!!

It is due for a recap. For a direct replacement of the exact values in your amp you would want the 16+32 kit. However the 32+32 kit will work perfectly well, with little effect on the tone.

Do you see the leaking bulge on the 50+50 cap? It is one of the center caps in the row of four mounted along the midline of the amp.

Recapping is just maintainance that should be done every 12-15 years if the amp is going to be gigged regularly. You might be fine to leave it as is for a while, but you don't want it to fail at an inopportune time.

Dr.HIWATT wrote:Nice Rig!!!

It is due for a recap. For a direct replacement of the exact values in your amp you would want the 16+32 kit. However the 32+32 kit will work perfectly well, with little effect on the tone.

Do you see the leaking bulge on the 50+50 cap? It is one of the center caps in the row of four mounted along the midline of the amp.

Recapping is just maintainance that should be done every 12-15 years if the amp is going to be gigged regularly. You might be fine to leave it as is for a while, but you don't want it to fail at an inopportune time.

thank you so much DR. HiWATT! I think I'm going to order the 16+32 kit to keep it all original.

Hm, at least one of my caps looks very similar. Do you think i need recap too? My amp is dead quiet, no problems at all.

It depends...

If you're gigging with the amp and need it 100% reliable, I'd say yes.

If you play it once in a while, and it more of a collector's piece, I'd say only if you want to.

IME, those caps still seem to work fine when they start "bulging." However, the place where that is happening is a relief vent, and the bubble indicates the cap is starting to generate gas. This only happens when the aluminum oxide/electrolyte start to break down, and as this deterioration progresses, the cap becomes less and less effective. In an extreme case, the bubble will burst and leave some cap guts in your chassis interior.

--mark

hi guys your the resident gurus ---so heres the deal -a tech sawpix of my amp my amp, its a 74 dr103 , yeah they have the bubble on top of em.. this amp sounds killer[heaven magic mojo as is!! my guy said im cooking the partridges by leaving dead caps in there , ill do the job , but am wondering if its gonna sound ..even better ? or omg not as good .. cause i think thats asking to much , and should i use the stock 16 +32 or go for the 32 +32 kit ? also im a novice , i can solder question is can a novice do this correctly and safely? also someone told me that hiwatts auto drain the caps at shutdown , is that true..., dont wanna find out in the er that the answer was no thanks guys

> my guy said im cooking the partridges by leaving dead caps in there ,
BS

> ill do the job , but am wondering if its gonna sound ..even better ?
> or omg not as good .. cause i think thats asking to much ,
Actually, yes. If you notice any change at all, it'll be tighter and stronger.

> and should i use the stock 16 +32 or go for the 32 +32 kit ?
I prefer the 32+32, but you'll never hear a difference between the two.

> also im a novice , i can solder question is can a novice do this correctly and safely?
Yes, but it is very difficult to do it neatly (without melting the wire insulation, etc.) if you're a novice.
Perhaps the good Doctor could put up a pictorial/tutorial as he has a clever method and has done a few.

> also someone told me that hiwatts auto drain the caps at shutdown , is that true.
Yes, that is true. The caps are normally discharged to safe levels in less time than it takes to remove the chassis from the cabinet.

--mark

I will have to see if I have any that need cap jobs.
I would be glad to do something like this if I have a patient and spare time.