Easy inexpensive tube buffer ideas?

[nordhaven]

Is there any simple/proven tube buffer plans out there for DIY? I like the Yaqin design that Pacific Valve & Electric has.

http://www.pacificvalve.us/YaqinTB.html

Simple single 6DJ8/6922 tube and one set of inputs.

[Karsten Sømand]

Hi nordhaven

I think this might be of interest for you?

http://eshop.diyclub.biz/product_inf...roducts_id=214

Karsten

[DougL]

This might fill the bill for you.

A Heretical Unity gain line stageA Heretical Unity gain line stage

You can eliminate or include the switching and volume controls.

HTH

Doug

[Miles Prower]

My first choice would be the White Cathode Follower. The Broskie CF doesn't look half-bad either.

[nordhaven]

Thanks for the info guys! lots of god ideas. They all use two tubes I see. I wonder if the Yaqin single tube has a negative effect on bandwidth or impedance? The white cathode follower looks interesting.

[Eli Duttman]

You can do a very good job with a single twin triode shared between the 2 channels. Use an ECC99 with its sections wired as cathode followers. CCS load the CFs. A bipolar PSU avoids the need for a cap. in the I/P circuitry.

[dshortt9]

I bought one of the Yaquin single tube units. It was running a 6922 at a very low 1 or 2 mils of current as a standard cathode follower and it made the signal sound way bloated, underdamped, and narrowed bandwidth. I replaced the cathode resistors to allow the tube to run at 4 mils and it was much improved. My purpose in buying it was to buffer the output of a passive preamp that had an 8k output impedance trying to drive a 20k input impedance to the power amp. after the changes it sounded pretty good. I would run it higher but I'm unsure of what the power transformer can deliver.