2. amps-preamps
  3. 1145581104

Need help to trouble shoot the noisy amp.

Gentlemen,

Not too long ago, I bought a pair of hybrid monoblock amp. One is dead quiet and the other is noisy but still plays good music. 90% of the amp is point to point wired so very easy to compaire the two. The noisy one is also running bit hotter and vibrates bit more on my touch.

Upon careful inspection, I've noticed that the power supply wires are connected (bunched up) differently. The quiet one is joined with (thick red + brown + black) & (thick white + white + light brown) combination. The noisy one is joined with (thick white + brown + black) & (thick red + white + light brown) combination. It has one big toroidal transformer and on small one connected to the input tube.

Could this be the problem? All other wirings are same on both. I'm tempting to re-wire the noisy one to see what happen. However, I don't want to distroy the amp either.

Big TIA for your kind advise....
zt000

Showing 3 responses by metro04

metro04
222 posts
 
Zt000,

I agree with albertporter about calling the manufacturer first, as it just takes a few minutes to verify. If not obtainable, and you have even basic electronic trouble shooting skills, and can locate a cheap volt meter (Home Depot, Radio Shack, etc), at least take some measurements before swapping the wiring. Mr. Porter and Gs5556 are right about their warnings, so, at least verify and discharge any HV caps before tinkering.
metro04
222 posts
 
Zt000,

I am a tech, but in Chicago.

Before going any further, remove all interconnect and speaker cables from both amps. Plug them into the same wall outlet, one at a time, and examine/compare them again.

Next, individually swap the tubes and perform the same exam. If both act alike, connect a speaker load to one amp and note opperation. Now swap to the other speaker for comparison. Do these steps with the other amp for comparison against the first.

If both amps act similar, plug them both in while verifying performance without speakers, then with.

Still matching in performance? Start connecting them back into the source component, and swap chnls if needed, should differences be detected. It could be the amp, but making sure through deduction.

Based on these test results, I'll have more info.

Let us know...

metro04
222 posts
 

Zt000,

I'll e-mail you and we'll further this off line, due to trivial technical correspondance. It'll be your choice to post any resolvement/findings.

In touch,
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