compatibility wise - pretty much same as with B1 buffer driving (any of tried) AVC/TVC
so, underlying difference - regular pot goes in front of B1K
TVC/AVC going after
so, you must take care of B1K not being overdriven, simply because it's seeing full signal all the time
tube part is critical, not input nor output buffer
so, see article for B1K in situation of 2Vrms going in
so, underlying difference - regular pot goes in front of B1K
TVC/AVC going after
so, you must take care of B1K not being overdriven, simply because it's seeing full signal all the time
tube part is critical, not input nor output buffer
so, see article for B1K in situation of 2Vrms going in
Hi, what did Nelson mean when he said you might see a little crosstalk on the input, I looked at the photo's in the build guide and I can't see any difference. Thanks.
Exactly what Ben Mah wrote. However, I really can't hear any crosstalk.
Nevertheless, I will change the wiring soon, because I will change some other things too.
What I don't get is that this is the photo from the DIY build guide, it too shows input jacks twisted together.
View attachment 1136027
Long ago, I recommended the idea of floating the Nutube. This recommendation was based on my experience with it taped down (as originally instructed). So I finally bit the bullet and followed my own recommendation. Removing the foam tape was difficult and risky. However, it solved pretty much all microphonic problems. Floated is undoubtedly much better than taped.
Good afternoon all.
Just finished my first B1 Nutube build and was for the most part successful. I am a newbie with limited skills but was able to complete the build with few items that I am unable to correct. Following the build ran diagnostics on T1 through T8 and the are all values are within spec. 10K pots are set at 9.52V left channel and 9.54V right channel.
My first question has to do with channel imbalance. From a volume setting of zero, as I increase volume, the left channel produces sound before the right channel and plays noticeably loader. It's not terrible but noticeable. I have scoured the forum pages but have not found a clear cause for this problem. Any information would be much appreciated. Hope to hear from you all soon, for now I turning my attention to cleaning up the room I blew up during this build!
Thanks, Oliver2112
Just finished my first B1 Nutube build and was for the most part successful. I am a newbie with limited skills but was able to complete the build with few items that I am unable to correct. Following the build ran diagnostics on T1 through T8 and the are all values are within spec. 10K pots are set at 9.52V left channel and 9.54V right channel.
My first question has to do with channel imbalance. From a volume setting of zero, as I increase volume, the left channel produces sound before the right channel and plays noticeably loader. It's not terrible but noticeable. I have scoured the forum pages but have not found a clear cause for this problem. Any information would be much appreciated. Hope to hear from you all soon, for now I turning my attention to cleaning up the room I blew up during this build!
Thanks, Oliver2112
Thanks for the reply 6L6. Had to Google low throw angle, is this a condition I will just have to live with or is there a fix?
Buy a few pots until you get one that tracks well enough you are not annoyed by it, or you could change it to a stepped potentiometer, they track identically at every position by design.
Perfect! Thanks for the input. Any stepped potentiometer you can recommend?
Side note. I took my time with the build over two days. Again, I am as lost as last years Easter egg when it comes to audio DIY. I have to admit the B1 sounds amazing.
Thanks again, Oliver2112
Side note. I took my time with the build over two days. Again, I am as lost as last years Easter egg when it comes to audio DIY. I have to admit the B1 sounds amazing.
Thanks again, Oliver2112
Forgot to mention I have a lot of gain using the B1. Would reducing the K value of the potentiometer reduce the gain going to the amp?
Gain stays, pot values only change how fast you reach your max volume. Gain is what it is, if you change it on this preamp, you change it's sound signature. Pops wrote about it.
Copy that, thanks Brijac. Think I will give a stepped potentiometer a try.
Thanks again for all your help.
Thanks again for all your help.
Olive2112
There is quite a range of attenuators available. You might try one of these : https://glass-ware.stores.yahoo.net/atandsise.html
At the expensive end there are DACT and Goldpoint versions of stepped attenuator.
A more accurate search term is stepped attenuator, not stepped potentiometer.
There is quite a range of attenuators available. You might try one of these : https://glass-ware.stores.yahoo.net/atandsise.html
At the expensive end there are DACT and Goldpoint versions of stepped attenuator.
A more accurate search term is stepped attenuator, not stepped potentiometer.