Bottlehead Forum

Bottlehead Kits => Legacy Kit Products => Topic started by: ptlud on June 13, 2018, 08:09:58 AM

Title: 5 Seconds of Hum When Stereomour is Powered On
Post by: ptlud on June 13, 2018, 08:09:58 AM
I have a Stereomour amp running with 2A3 tubes and driving 100 dB/m speakers.

When I turn on the amp, hum is noticed from both speakers for approximately 5 seconds.  After that, dead silence.

Any suggestions on the cause of this issue and how to "fix" it?

Thanks!
Title: Re: 5 Seconds of Hum When Stereomour is Powered On
Post by: Paul Birkeland on June 13, 2018, 08:18:51 AM
There's nothing to fix here, there will be some noise between when you power the amp on and the 2A3s start conducting.

One measure to reduce the level of the noise is to rewire the output transformers for a lower impedance setting. 
Title: Re: 5 Seconds of Hum When Stereomour is Powered On
Post by: ptlud on June 13, 2018, 09:21:48 AM
Great.  Thanks for the information.

I love the amp.