Amp repair cost — is this right?

I speak with some knowledge since i’ve designed many commercial amps, and recently re-capped, mostly as a favor, a dozen or so ~30 year old units that i know the owners of and were sold under my own label(s). Its a total PITA.

Just an aside, i received some bogus (Chinese counterfeit) caps and had to do 2 a 2nd time!

Some caps can be very expensive, large, high voltage computer grade caps can be $30-70 each. Fortunately it looks like that unit (per the pic provided above) has more common snap-in radial ’lytics that are vastly cheaper. (like 1/4 or less of that, "depending")


Georgehifi, with a pic, paints a reasonable story. I think the price *may* be a little high, but here’s the thing. every amp is different to work on - some come apart easily, some less so. There are several hours on each end of this job before caps are removed or replaced.

Without the specifics answers are meaningless. I would guess, nothing more, 6-10 hours total and $100-250 in parts. I didn’t bother to look for and count the smaller caps.

So was the price high? Likely somewhat. Was it crazy? not really. Its a messy job. What do you pay your tech, or at a small firm, maybe an engineer?

G

@teo_audio:
$100 to take it apart, remove the PCB, remove all the caps, buy new ones, put them in, pre-test, re-assemble, final test?
If so I will hire you as a tech tomorrow :-)
G

In Australia a "reputable repair shop" charges $115-$130aud per hr that $80-$90usd.
Like I said it would take a tech that "cares" about a day to do this properly heat soaked and biased back up. And then there’s the "quality" parts 16 x large power supply caps
https://www.newark.com/cornell-dubilier/381ll682m063a052/cap-6800uf-63v-alu-elec-snap-in/dp/54AH2158...
and around 20 smaller electrolytic caps.
THE PRICE SEEMS FAIR!!!!!!!!!!!!!!!!!

Cheers George

Now George, there you go bringing data in... can't have that.:-)
Surprised how costly those caps are.  I buy them quite a bit "better" but yea, they cost!  And to the above folks talking about "better" caps - by virtue of being new the large 'lytics will work much better.  But we are  talking about electrolytic capacitors. These are not audiophile pretty much by definition - they will be paralleled with much better film type caps (i hope!).  So will it be better?  Than B4, yes.  better than new?  Likely not much, although we can buy larger caps in the same package today, so maybe in that respect. Will it last 20 years?  The ones i did already were 30 years old.
CDE are very good caps.
G

Building my own I am free to use polypropylene power supply capacitors instead which have an unlimited shelf life and do not wear out. For the 1kV power supply to my final stage of SET amplification I use polypropylene capacitors rated at 2400 Volts. It costs little to use overrated components which will not go bad in the future.

Uh, so how much does it cost you and what's the size, using polypropylene film caps, for a modest power supply (remember the OP's amp is solid state) of maybe 2400uF at 600V (for your tube unit). Now think, 50,000uF at 63V (total) for his solid state amp.
I believe some ROM data points will show the impacticaility of this path especially in an existing form factor.
Just some quick estimates - among the most affordable PP caps are Wima.  A 1uF/100V cap is roughly a buck.  Maybe $0.50 in large quantity. (e.g.MKP-10 series).  x 50,000. Math seems simple to me!
Oh they would also be the size of a carry-on suitcase.
G

It's the ones that go off on a tangent with esoteric replacement parts that make me pause.

Yes, missed the point of re-capping 'lytics whcih are without doubt already bypassed with poly-something film :-)