Recapping my anthem amp and found this

Tonyr1084

Joined Sep 24, 2015
9,744
Capacitors are rated for voltage as well as capacitance. In the case of voltage, say you're running a 12 volt circuit. In that case a 16 volt cap will do just fine. But if you're running a 15 volt circuit then a 16 volt cap doesn't have enough head room and MIGHT NOT be suitable. It may work, it might not survive. In that case you'll want the next higher rated cap, which might be 35 volts. But that doesn't mean the circuit is running at 35 volts, it just means the cap is considered safe up to that voltage. So 15 volts on a 16 volt cap might be safe, there's a chance it might not be. A good engineer will allow himself (or herself) head room for those unforeseen circumstances like voltage spikes and such. Like @MisterBill2 said, it's the actual voltage that matters.
 

Thread Starter

ssmokeyy

Joined Jun 7, 2023
24
Mister i have looked can't find a build or repair spec sheet. Anthem has only given it to a couple repair places and those places won't talk about it.
 

wraujr

Joined Jun 28, 2022
260
Looks like the "USP" series that according to the current Rubycon catalog was discontinued at the end of 1999. So these could be over 20 years old... Replaced by USG series and here is current offering:
1687444647474.png

1687444741849.png
 

wraujr

Joined Jun 28, 2022
260
Mister i have looked can't find a build or repair spec sheet. Anthem has only given it to a couple repair places and those places won't talk about it.
I think what he is asking is that since we don't have schematic, have you measured the DC voltage across the power supply caps with the power on? A typical derating is that the cap rated voltage should be 25% over the actual designed/operating voltage. So if you measured 75VDC then the cap should be rated 1.25 * 75 = 94V (hence the 100V rating the manufacturer used).
 

BobTPH

Joined Jun 5, 2013
11,557
From an ad:
Power output: 180 watts per channel into 8Ω (x 5 channels)
That would require 54V peak + a couple of volts extra, so maybe 60V. 80V is probably a reasonable voltage rating for the caps.
 

MisterBill2

Joined Jan 23, 2018
27,679
Mister i have looked can't find a build or repair spec sheet. Anthem has only given it to a couple repair places and those places won't talk about it.
If no information is available then you will need to apply power and measure the applied voltage at the capacitor. That should not require operation, but only powering the amplifier. But with all of the components connected.
 

MisterBill2

Joined Jan 23, 2018
27,679
It is common to list the power output of lower price amplifiers at 10% distortion because that is a larger number. That does not make it a useful number for those wanting listening quality sound, though. Giving that specification indicates the anticipated type of users, and is a negative reflection on the producer. At least that is my take on it. My Maramtz 2235 only lists the 0.1% distortion at 35 watts out.
 

BobTPH

Joined Jun 5, 2013
11,557
Um, did anyone read the specs? It says 180W at <1.0% distortion.

And I donn’t know why you are calling a $4000 amp cheap.
 

Thread Starter

ssmokeyy

Joined Jun 7, 2023
24
If I only hook up 3 of the 5 modules would that lower the main rail cap voltage? Just wondering if there is ways to listen what these 80v caps would see? I'm sure there is part of this I don't know that controls the voltage the caps get.
 

MisterBill2

Joined Jan 23, 2018
27,679
If I only hook up 3 of the 5 modules would that lower the main rail cap voltage? Just wondering if there is ways to listen what these 80v caps would see? I'm sure there is part of this I don't know that controls the voltage the caps get.
For a nonregulated power supply, the voltage falls as the load rises. So with only three of the amplifier modules connected it might be a bit higher. But it should be close enough to know if the 80 volt rating is adequate. There is no simple way to "listen" to a voltage level that I am aware of. You will need a voltmeter with an adequate range.
 

Audioguru again

Joined Oct 21, 2019
6,826
The voltage on the large capacitors is directly related to the electricity voltage that could be higher than normal if you are close to an electricity distribution transformer and at times when people are not using much electricity.
My "115VAC" measures 123VAC because my home is near a distribution transformer.
 
Top