I just completed restoring one of my MK 3 amps with VTA board and SDS PS. I was making adjustments on the bench and noticed a very slight hum/buzzing noise coming from the speaker. After checking grounds, tubes, etc, I noticed that the noise disappears once an rca plug is inserted into the input jack. Does anyone know if this is normal?
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Hum/Buzzing Noise
Bob Latino- Admin
- Posts : 3276
Join date : 2008-11-26
Location : Massachusetts
rudes wrote:I just completed restoring one of my MK 3 amps with VTA board and SDS PS. I was making adjustments on the bench and noticed a very slight hum/buzzing noise coming from the speaker. After checking grounds, tubes, etc, I noticed that the noise disappears once an rca plug is inserted into the input jack. Does anyone know if this is normal?
This is normal ... If the RCA input jacks are left open and not terminated with RCA interconnects connected to your preamp on the other end, your Mark III will give you a little hum/buzz through the speakers.
Bob
Last edited by Bob Latino on Fri Dec 07, 2012 10:51 am; edited 1 time in total
rudes- Posts : 63
Join date : 2012-03-07
Thanks Bob!