@ - three-easy-payments
I believe the hum IS being created by my amps. I am hoping there is a solution available. The hum is only audible when the music is not playing, even at low levels.
Thank you,
Jose |
MBL 111f speakers are not powered. The hum i am hearing is coming out of the speakers once i power on the amplifiers. Therefore, it is the wall outlets or amplifiers that are generating/transferring the hum into the speakers. Can someone recommend me a product to minimize the hum? One (product/solution) they have personally used to good effect? Thank you in advance. These amps require (necessary) 20A power supply lines. I had 2 dedicated lines installed, one for each monoblock since my room only had one 15A line.
@millercarbon - the intent of my query was never meant to be confusing. Thank you for pointing that out.
Best,
Jose |
Update, I unplugged the 6m long XLR from each amp. Then, I powered on both amps. There was no hum at all.
@jea48
All instruments are plugged into a Silver Circle audio, "pure power one 5.0, which is plugged into an existing outlet.
Pre = ARC Ref 3
Phono = DSA
Tuner = McIntosh MR 67
Transport = ML No31
Dac = ML 36s
TT = Final audio VTT-1
Tonearms = Talea and Kuzma 4pt
Best,
Jose |
All was unplugged from the back of the pre, I still have "hum".
I ran a ground wire from the pre power cord (plugged into the back of the power distributor) to the ground of wall outlet the power distributor is plugged into; the hum remains...??
Many thanks for all advice given,
Jose |
Update - the pre is plugged into a common 15A outlet; the amps are plugged into a dedicated 20A outlet and ALL else is unplugged. I still hear the same amount of hum.
I installed a "cheater plug" between the pre and wall outlet, I hear less hum than before, about 70% less. I cannot hear hum from my listening position (10ft) away.
The "common" 15A leg has 7 outlets, 3 of which are being used. 1 outlet in particular has my humidor plugged into it. Unplugging everything from this 15A leg yields no change.
Thank you,
Jose |
@jea48 - the cable line plug is a wall-wart and does not have a ground pin. It is not tied (a part of) the sound system. I'm not sure when i first heard it...you see, I'm alternating amplifiers (also use ML 33H) and did not pay it much attention. I will certainly try what you are suggesting and report back. Thank you for contributing.
Respectfully,
Jose |
Thank you all for taking the time. After my first failed attempt last night, I decided to plug all "in" and listen to music instead :-)
Tonight, I will try what has been recommended. Something else I forgot to mention; I have a cable line and box in this room. The cable line runs parallel to the XLR (they do not touch) and is also plugged into the same 15A outlet the power distributor is plugged into...
with kind regards,
Jose |
Al, thank you for such a lengthy explanation.
I plugged EVERYTHING as before, with one exception, there is a "ground cheater " between the pre and power distributor. The hum is 50% less than first posted.
I tried both amps on the same outlet - no change.
The pre uses a 6L6 tube.
Maybe, I will try some of the grounding devices suggested. Funny thing is, I've been wanting to upgrade my pre...😀
Respectfully,
Jose
|
When I get home, I will look for the Krell manual and see if it states the input impedance. Additionally, I will unplug the tuner.
Come to think of it, prior to experiencing the hum issue, I was using my Sansui TUX-1 tuner, so it may be the introduction of the McIntosh, (I'm always alternating gear)...
Those Jensen look to be the ticket.
with best regards,
Jose |
Gentlemen, please allow me to be COMPLETELY off-topic.
I am humbled by all the thought processes and the suggestions you have provided. Audiogon is filled with back and forth banter, so much so, that there are many recent posts about it...However, you prove that this is a site where help and assistance is given/provided, Thank you.
@jea48 - Yes, everything was was reinstalled as before. The one exception was the ground plug installed between the pre and power distributor (hum was reduced to 50% less of when i first posted). It would be easy to plug the 5.0 into one of the unused 20A outlet, as would be to move the Pre. Having to Move everything would require MUCH work. Could I use a long heavy-duty power cord plugged into one of the 20A outlet to power the 5.0 distributor where it sits without moving it?
I have a Coda 02b preamp, I will try it tonight and check for hum.
Respectfully,
Jose |
Update:
1. All was left as initially, I only powered up the amp; very low hum from the speakers (ear against the speaker). Could not be heard from 1 ft. away.
2. Unplugged pre from back of distributor and turned ON the distributor. No change from above.
3. Plugged in Pre, the hum increased significantly.
4. Unplugged distributor from common 15A outlet. Ran a 10ft cord from unused 20A dedicated outlet to the distributor and powered on. Same outcome as noted above; maybe...slightly less hum.
I will try another Pre and report back. I have to take my son to pitching lessons. 😀
Regards,
Jose |
Update:
I replaced the 6L6 tube and left all else the same; the hum can only be heard from 18inches away, without any music. Also, the hum is of a lower frequency. I can tolerate this for the time being.
I am going to replace the ARC Ref3. I haven't made up my mind as to my next preamp choice.
Thank you all for helping.
Happy Holidays,
Jose |
