Stereomour Teething Pains!
- Thread starter M42
- Start date
Grainger49
New member
Jeff,
You are in luck, you have two 2A3s in your amp. Try swapping them from left to right.
The likelihood of you having two bad 2A3s is slim.
You are in luck, you have two 2A3s in your amp. Try swapping them from left to right.
The likelihood of you having two bad 2A3s is slim.
Grainger49
New member
Jeff,
I suppose you have determined the hum is in both channels. Also that you have tweaked the hum pots down (after swapping tubes) to a minimum AC reading.
So if it is in both channels swapping and starting with one out doesn't make sense... to me.
Nearfield listening you can hear hum that isn't obvious at 5-6 feet. But with inefficient speakers it should be very low.
I think there are other Bottleheads in Ottawa. But you need to start a new thread in the General folder asking for local help.
Just to check, move all components apart. The turntable the farthest away from the Stereomour, the Reduction at the full length of the interconnect from the Stereomour and the Crack unplugged and not connected to the system at all.
We are trying to eliminate all variables. Eliminate the Crack all together, move the transformers, and motor as far away from each other as possible.
I admit, I am grasping at straws. You have followed all other instructions to the letter and this is baffling.
I suppose you have determined the hum is in both channels. Also that you have tweaked the hum pots down (after swapping tubes) to a minimum AC reading.
So if it is in both channels swapping and starting with one out doesn't make sense... to me.
Nearfield listening you can hear hum that isn't obvious at 5-6 feet. But with inefficient speakers it should be very low.
I think there are other Bottleheads in Ottawa. But you need to start a new thread in the General folder asking for local help.
Just to check, move all components apart. The turntable the farthest away from the Stereomour, the Reduction at the full length of the interconnect from the Stereomour and the Crack unplugged and not connected to the system at all.
We are trying to eliminate all variables. Eliminate the Crack all together, move the transformers, and motor as far away from each other as possible.
I admit, I am grasping at straws. You have followed all other instructions to the letter and this is baffling.
Just a question : is it a hum or some hiss ? I have no hum, except the around 1.4 mV I can here when I put my ears against the speakers. But I have clearly some audible hiss, a white noise, that I can't get rid of and that is audible in the whole room, especially at night when there isn't another noise around.
Grainger has a FAQ post about the difference between hiss and hum.
I tried changing my 12AT7 tube without any luck. Reading around, here is some information with a workaround with hiss, by PJ : http://www.bottlehead.com/smf/index.php?topic=4521.0
Best wishes.
Grainger has a FAQ post about the difference between hiss and hum.
I tried changing my 12AT7 tube without any luck. Reading around, here is some information with a workaround with hiss, by PJ : http://www.bottlehead.com/smf/index.php?topic=4521.0
Best wishes.
Once I have a little more time I will move the components as you have suggested Grainger and report back. Thank you for your continued input, it's much appreciated. Fabian, in answer to your question....I have both, hiss and hum even with the volume control at minimum settings. As far as I can remember, the amp was dead silent (at the speakers) at lower volume settings. The hum/hiss seemed to become audible at the speakers at about the 100 hour mark or so. The amp has just under 200 hours on it now. What perplexes me most at this point is the continued hum at the transformer, which disappears when you touch the transformer bell (not the transformer laminations). Nothing is loose. Additionally on startup a humming noise is heard through the speakers for about six to eight seconds then abruptly drops to a much lower level. I've obviously stuffed something up on the build...I'm determined to find it and fix it.
Jeff
Jeff
Hi Jeff, M42
You asked the question who lives in Ottawa. There are a couple of us. I live in Stittsville and I believe a member mchurch does too, although I haven't heard from him in awhile.
I am a junior Bottleheader. I have built and upgraded a Crack along with a upgraded Quickie. If you need a second set of eyes or other components to try to narrow down your focus I would be willing to help.
As you can see in your thread, this forum is wonderful and the people hear will get you up and running. You don't have to worry about that. I am also thinking of getting either a Sex or Stereomour. I would love to hear yours.
Send me a PM if you would like.
Take care....Dave
You asked the question who lives in Ottawa. There are a couple of us. I live in Stittsville and I believe a member mchurch does too, although I haven't heard from him in awhile.
I am a junior Bottleheader. I have built and upgraded a Crack along with a upgraded Quickie. If you need a second set of eyes or other components to try to narrow down your focus I would be willing to help.
As you can see in your thread, this forum is wonderful and the people hear will get you up and running. You don't have to worry about that. I am also thinking of getting either a Sex or Stereomour. I would love to hear yours.
Send me a PM if you would like.
Take care....Dave
Hi Dave,
I have to agree, the forum and its members are a wonderful resource indeed. Where else can you get, in many instances, almost real time responses to your questions...and often from the designers themselves! It's nice to hear there are at least a few of us here in the Ottawa area. You're more than welcome to have a listen to my amp...despite my perceived shortcomings with my build, the thing still sounds amazing! Thanks for your offer to help...I'll send you a pm.
Jeff
I have to agree, the forum and its members are a wonderful resource indeed. Where else can you get, in many instances, almost real time responses to your questions...and often from the designers themselves! It's nice to hear there are at least a few of us here in the Ottawa area. You're more than welcome to have a listen to my amp...despite my perceived shortcomings with my build, the thing still sounds amazing! Thanks for your offer to help...I'll send you a pm.
Jeff
