"Pre-amps 101"

[BobM]

Wait until you start rolling caps!   then the fun begins
Mike

He ordered it with Sonicap Platinums inside, so no need to roll anything - a great cap.

[topround]

Teflon would be my choice as well!
especially in that position

[Face]

I'm using a Dodd 6H30 DR buffer as a pre, I'm sure his variable gain 6H30 pre sounds just as good.

FYI, Parts Connexion sells the 6H30DR super tube, and AFAIK, everything they sell is on sale until the end of the month. 

[rpf]

Wait until you start rolling caps!   then the fun begins
Mike

He ordered it with Sonicap Platinums inside, so no need to roll anything - a great cap.

They might work; esp. as Bill's speakers are fairly forgiving.

I found they were overly smooth, i.e., slippery sounding, in the Dodd Mono 50s I had. They did not convey the full texture/harmonics of instruments. I replaced them with REL Audiocap PCUs, which did provide the missing elements and conveyed even more resolution. The PCUs were more expensive, of course.

[richidoo]

To DR or not to DR?
http://www.whatsbestforum.com/showthread.php?2155-6H30-s-Are-the-more-expensive-megabuck-versions-worth-the-money

[StereoNut]

FYI

Being the tube "newbie" that I am, I'm not sure what the difference is (other than the tubes being a lot less expensive, which is fine with me!) but the Dodd Audio VGP I'm getting (which is Gary Dodd's latest design) has (4) 12B4A's in it - not (2) 6H30's as before.

I hope this clears things up a bit.

SN

[StereoNut]

Congradulations!
Let us know how it sounds . looks like a nice design
I would love to try his Phono pre with Slagle stepups.
I like the idea of batteries, one less power cord to screw things up

Wait until you start rolling caps!   then the fun begins
but is very easy to solder in caps takes 2 minutes, and really does make a difference, but they get expensive fast

enjoy

Mike

What's ironic Mike, is that Triode Pete was the person who gave this Dodd pre an extremely high recommendation to me (after sharing a display room at RMAF with Gary Dodd and listening to his gear for 3 days) meanwhile, Pete sells power cords!  

[rollo]

Well our demo piece is on the way as well. Went with DR version using Mundorf Silver/Gold caps.
   Swap Meet Audio will be offering in home demo. Now you will need an PI Audio  Battery Buss.


charles

[StereoNut]

Well our demo piece is on the way as well. Went with DR version using Mundorf Silver/Gold caps.
  Swap Meet Audio will be offering in home demo. Now you will need an PI Audio  Battery Buss.

charles

Charles, what's the "DR" stand for?  Also, send me more info. on the PI Audio Battery Buss... I don't know how that fit's into the overall scheme of the Dodd pre.  Especially if it effects what I'm buying for a charger and battery.

Thanks!

SN

P.S. - I went with the Platinum Sonicaps.  The Mundorf Silver/Gold caps were too rich for my blood!

[DaveC]

I found they were overly smooth, i.e., slippery sounding, in the Dodd Mono 50s I had. They did not convey the full texture/harmonics of instruments. I replaced them with REL Audiocap PCUs, which did provide the missing elements and conveyed even more resolution. The PCUs were more expensive, of course.

I have the PCUs in my amp, it's the only coupling cap in the system and they are very good caps.

[richidoo]

DR is the suffix marking the brand. The whole tube name is 6H30DR, and this is the original 6H30 type produced by Reflektor, for use in Soviet fighter planes.  The other option is Sovtek which is good, used by AR in all of their tube products. BAT dubbed the DR version the "supertube" and for a while claimed to be the exclusive importer of the tube to US.

So DR is only related to 6H30 tubes.

I'll have to read up on 12B4A type. Don't know much about that.

[StereoNut]

DR is the suffix marking the brand. The whole tube name is 6H30DR, and this is the original 6H30 type produced by Reflektor, for use in Soviet fighter planes.  The other option is Sovtek which is good, used by AR in all of their tube products. BAT dubbed the DR version the "supertube" and for a while claimed to be the exclusive importer of the tube to US.

So DR is only related to 6H30 tubes.

I'll have to read up on 12B4A type. Don't know much about that.

Thanks, Rich.  Keep me posted! 

[richidoo]

12B4A is a 9pin, indirectly heated power triode used in vertical deflection amplifiers in TVs. Plate dissipation is 5.5W,so it can make an honest 1W output power, that's a lot for a preamp tube.

Jim McShane has listed:
(6) 12B4 RCA NOS/NIB black plates! These are extra nice versions of a popular tube, $9.50 ea., $21.50/pair.
http://www.mcshanedesign.net/tubes.htm

That's all I could find in 10 minutes.  Enjoy whatever Gary puts in there for a while til you get it broken in. The tube info will come to ya if you're curious.

[StereoNut]

You da man, Rich!  

Gary said to me that his latest design VGP had good news and bad.  The "bad" news is it has four (4) tubes in it, not two (2)... the good news is the 4 tubes collectively cost about 1/5 of what the pair of NOS 6H30's would cost on a re-tube.

The best news is that Gary feels the quartet of new (12B4A) tubes sound even better than the pair of NOS 6H30's that he recommended in the previous design.

SN

[rpf]

The 6H30 DRs are old stock tubes: they went out of production in the early-mid '90s. They are far better than the new Sovtek production.

Somewhere in between in quality is the Electro-Harmonix gold pin 6H30s (at least in the Modwright 36.5 I had). They are, however, about the same price as the Sovtek.