I have considere that, but when I turn the volume up so will my loudspeakers- and my wife. I am trying to avoid introducing a on/off switch in the loudspeaker circuit. But that may not be possible.
Folks, has someone done a BOM for this so that we don't need to wait until the kit is available again?
My mistake - I thought you were referring to a replacing the buffers in the B1K circuit from this thread with bi-polar supply versions. I misunderstood your post. Sorry.
Here is a Mouser project list for V1R1 board w/ JFETS. Parts are in stock today, consisting of PCB components and power supply only.
Mouser Electronics
“Folks, has someone done a BOM for this so that we don't need to wait until the kit is available again?”
I think he means the rest of the kit, no? I so wish the kit would appear.
I think he means the rest of the kit, no? I so wish the kit would appear.
I have built the B1 with a remote controlled relay attenuator... it is quite nice.
Although, I do have microphonic ringing when changing volume.... I didn't think the movement of relays would affect the Nutube that much but it does. It is VERY audible, even with music playing.
I mounted the Nutube with 2 layers of double sided tape.... what are other approaches that can be used?
Are there any good isolating grommets to put between the standoff and chassis that could help?
Note: The empty space is intended to add the remote controlled input switch, and then 5V battery pack to isolate the volume control from the screen/controller.
Although, I do have microphonic ringing when changing volume.... I didn't think the movement of relays would affect the Nutube that much but it does. It is VERY audible, even with music playing.
I mounted the Nutube with 2 layers of double sided tape.... what are other approaches that can be used?
Are there any good isolating grommets to put between the standoff and chassis that could help?
Note: The empty space is intended to add the remote controlled input switch, and then 5V battery pack to isolate the volume control from the screen/controller.
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When play music test your chassis cover and all around the box is closed ?
It's a help for avoid microphonic 🙂 Nice build btw.
It's a help for avoid microphonic 🙂 Nice build btw.
6L6 recommends a specific eraser taped to the top of the NuTube:
https://amazon.com/gp/product/B005ENNEJW/ref=ox_sc_act_title_1?smid=AY2ANYVC1YIBT&psc=1
I have used this product, which has good self adhesion:
https://amazon.com/gp/product/B000BQMFEC/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
https://amazon.com/gp/product/B005ENNEJW/ref=ox_sc_act_title_1?smid=AY2ANYVC1YIBT&psc=1
I have used this product, which has good self adhesion:
https://amazon.com/gp/product/B000BQMFEC/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Thanks! Actually the chassis was open... I'll try it closed.
avdesignguru, I'll take a look at those as well
You might also try "floating" the relay board on some type of isolation standoffs, in case the relays are transmitting vibration directly PCB to PCB via the standoffs.
Yea, I think thats the issue. I put rubber grommets under the Korg PCB and it isn't enough. I think I'll try grommets under both PCB's.
What do you do with the putty ? 🙂
The tube is already mounted with double-sided tape under it BTW..
What do you do with the putty ? 🙂
The tube is already mounted with double-sided tape under it BTW..
Putty goes on the top side glass to reduce airborne pickup from the top. You could try completely letting the relay board "float" temporarily with a bit of loose foam or something under it to keep it off the chassis - total isolation, nothing passing through the mounting screws. See if that works and if so, figure out something more permanent. You can also try damping the relay cases somehow, similar to the top of the NuTube.
Also, NuTubes vary in their microphonics. A good one will exhibit little or no ringing that dies out immediately when tapped lightly with a fingernail. A bad one will ring either a long time or continuously when tapped. This is typically caused by the filament vibrating, usually somewhere around 5KHz.
Thanks, will try both the putty and floating the board.
I'll try to see how it behaves with the tap. When changing volume via the remote, the ringing lists ~3-5 seconds, gradually fading away.
It's a kit a friend from Russia bought for me ... it's pretty great actually. It comes with IO board, volume control, and display/controller. I'll posts pics of my build once I've fully integrated it.
I actually couldn't find a place to buy this online anywhere, but send me a PM and I'll send you an email you can inquiry at (if you're interested).
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