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Output test on amp

Is there a way to test frequency response vs dB output with a test record and multimeter?

im trying to determine if both channels are outputting all frequencies at equal outputs. 
If not is there another way to achieve this at home. 
last_lemming
erik_squires
16,892 posts
 
No.

The problem with multimeters is they tend to be limited to a few hundred hertz.

Your easiest/cheapest solution is to use a cell phone with a calibrated mic:

https://amzn.to/2V3ahik

and appropriate software.  I use Audio Tools on android.

To see if a problem is an amp or a speaker, swap speakers.

Of course, you can also get really fancy and go with Room EQ Wizard or OmniMic.
roberjerman
4,319 posts
 
All power amps (and preamps) have linear (flat) response out to their upper and lower limits, where they roll-off in the ultra-sonic and sub-sonic regions. So no need to worry! 
looscannon
60 posts
 
Many amps actually go right down to DC. The upper limit is peculiar to that am and it's design but I no of no amp that does not pass by 20 kHz gracefully. What is it exactly that you are worried about and why?
looscannon
60 posts
 
I would get a digital test album like this one  https://www.hdtracks.com/#/album/5ddb5ef3848da9f501f6db95
Then you will need a broad bandwidth multimeter. This will check everything but your turntable. For that get the Hi Fi News Test Record. 
last_lemming OP
639 posts
 
I have a 30 year old ARC CL 60 that appears to be a few decibels down in the higher frequencies in the right channel.  But it’s subtle; so I’m not 100% sure. 
I have eliminated all of he other variables including,  it not limited to, cables, tubes, flip flopping speakers - and tubes and sources. So I figured I do an empirical test before sending it in. 
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