SixAPre

[Paul Joppa]

Just to be clear, the BeePre was designed and "tuned" around the EH 300B. It is a fortuitous accident that a 6A3 will also work.

[Chris65]

As Paul said, it is just fortuitous that the 6A3 will work in the BeePre. I would concentrate on the 300B & think of the 6A3 as a different 'flavour' you can try at some point.
It's a while since I had 6A3's in the BeePre, but I don't recall any noticeable difference in gain & no 'improvement' in sound, just a slightly different presentation.
Buying NOS tubes on Ebay is a crapshoot at the best of times. There are plenty of NOS tube dealers who know what they're doing & usually cost less than what you'll pay on Ebay. Just checked a few sites and NOS 6A3 go for $25-40 each.

[kip.duff]

Chris65:

What are you running in your Beepre?  Any favorites?

I'm always interested to find better tube sources- if you have a moment, I'd appreciate it if you could direct me to some of the quality tube vendors you mentioned. 

Of course, there's always this option:

http://www.ebay.com/itm/MP-of-Western-Electric-300B-Tube-Double-Square-Getter-NOS-NIB-Date-code-6539-/301635864396?hash=item463ae6074c:g:IfIAAOSw0vBUcAM5

WOW!

Thanks for your time, Kip..........

[STURMJ]

I have been using Sylvania NOS 6A3s and have been very happy with them. They are not as tall as 300Bs and fit better in my rack. I do have a pair of JJs and EHs for it, but they barely touch the bottom of the shelf above the amp.

[kip.duff]

I have been using Sylvania NOS 6A3s and have been very happy with them. They are not as tall as 300Bs and fit better in my rack. I do have a pair of JJs and EHs for it, but they barely touch the bottom of the shelf above the amp.

Other than the rack issue, do you have a favorite- or all pretty close?

[RPMac]

I use 6A3's as my "everyday" tubes because of $$$$. ( Raytheons right now ) l've had good luck from eBay.

As Doc said, the BeePre was developed and voiced with EH 300B's...probably the best place to start.

I agree with Chris, it's a matter of "flavor". Depends on speakers and room effects, then what amp, and then what you like.

I believe the design and using a DHT makes it a great preamp. Thanks PJ!!

Would be interesting if PJ could come up with a mod to use 10Y family of tubes.

[Paul Birkeland]

Would be interesting if PJ could come up with a mod to use 10Y family of tubes.

The 10Y needs a lot more plate voltage than is available in the BeePre to run in class A1, which makes it not such a suitable choice.


I was commissioned not that long ago to build a preamp using the 12A/112A.  The microphony was very difficult to deal with, and required a significant redesign to the circuit that ultimately undermined the compatibility of the preamp significantly. 

In the simplest terms, the 12A can only run 10% of the current and will have 10x the output impedance with more microphony...

[Chris65]

Chris65:What are you running in your Beepre?  Any favorites?
I'm always interested to find better tube sources- if you have a moment, I'd appreciate it if you could direct me to some of the quality tube vendors you mentioned.

No particular favorite, usually running 300B, sometimes 6A3. I enjoy both. And a 6B4G with adapter works too.

If you search 'NOS tube suppliers' you'll find plenty of dealers. Also try vintage radio parts or similar.
I've had, or heard of good experiences from these but there are many others (guess it's ok to post links? )
https://vacuumtubesinc.com
http://www.findatube.com
http://www.vacuumtubes.net

[STURMJ]

Other than the rack issue, do you have a favorite- or all pretty close?

Pretty close, 300b is slightly more detailed.

[kip.duff]

Chris65:

I also found The Tube Center in Orlando.

http://www.thetubecenter.com/

I think the reason I might not have paid much attention when I stumbled across a site like these is that there is not a lot of detail or specific info like photos, possible matching, written description, etc.  Guess that's because you're getting a better price and they don't have time for the advertising and presentation.  Also, I believe they do not  sort or match as much- if at all.  Just missed getting some 6A3's for $35 each at The Tube Center.

[scotth]

Chris65:

I also found The Tube Center in Orlando.

I don't get it. Do you have to call to see what is in stock or what brands/types of each tube are available? Seems weird that they have 1 price listed for each tube type. Some of which seem very very low.

[kip.duff]

scotth:

I called the guy at the Tube Center, and he was real approachable.  The website says they have 3.5 million tubes under one roof.  He described the tubes, and said someone bought all six.  Asked me to email him with info on tubes I was looking for, and he would call me when some more came in.  Does not offer matching, but he said he felt that if the tubes were in a lot, might be close enough anyway.

I'm starting to wonder how important matching is in this application- does C4S reduce the importance of matching?  Is it important at all?  I get the impression that many people may be using unmatched tubes in their BottleHead equipment, but don't really know.

[Chris65]

I also found The Tube Center in Orlando.
I think the reason I might not have paid much attention when I stumbled across a site like these is that there is not a lot of detail or specific info like photos, possible matching, written description, etc. 

Yes, as I said there are many tube suppliers. If you're concerned about details like this, you can always ask.
It would be a massive task to sort this kind detail if any sizeable amount of stock was held.

For info:

Matching between channels in a single ended amp is not particularly important. -PB

[Analogluvr]

No particular favorite, usually running 300B, sometimes 6A3. I enjoy both. And a 6B4G with adapter works too.

If you search 'NOS tube suppliers' you'll find plenty of dealers. Also try vintage radio parts or similar.
I've had, or heard of good experiences from these but there are many others (guess it's ok to post links? )
https://vacuumtubesinc.com
http://www.findatube.com
http://www.vacuumtubes.net

Any idea where I can get tube socket adapters so I can run the 6b4g

[Leland Hankins]

Ebay