[abernardi]

Hi Everyone,
   I wanted to introduce myself to this group, my name is Adam and I just picked up a used Avastar Hybrid pre-amp from a fellow audiophile friend.  My old preamp had bit the dust and I was going directly from my EAR 834P phono preamp into a Marchand XM126 tube active crossover into a couple of BEL (Brown Electronic Labs) solid state amps.  I was very happy with that set up, since the EAR has a volume pot on board, but obviously I was limited to vinyl only, which was good for me 95% of the time.  But there were some times I wanted to go to my digital library, so I was passively looking for a good transparent preamp. 
  Let me say, I am VERY happy with this box.  Overall, it has improved my listening experience which was unexpected.  The most obvious improvement is that the image is more three dimensional, the music comes into the room more and it seems like the instruments are more layered (one in front of the other, particularly in big band music).  Next, the image is wider, going well beyond the speakers on some material and things seem just a bit more lively, more energetic.
  The only two downsides I've noticed are, 1, a very slight loss of directness to the source (but I might be imagining that), and 2, a very slight sheen that might have been there already, again, so subtle I'm not sure if I'm imagining it.
  The unit is very very quiet and seems really well built and designed.  And I love the remote volume control!  I've had it in my system for about a month now and it's a keeper.
  I'm also surprised that it sounds the same as the day I put it in my system.  Pretty much everything I've put into my system needed some break in time, even used equipment and cables, but this just took it's place quietly and solidly.  Any insights into this preamp would be greatly appreciated!!

[aln]

Simple things like changing the tubes can be helpfull.  Even just cleaning the pins on your current tubes (pro gold) can reap benefits.  Cleaning all of the switches and the volume pot also is a good ides.  Have fun!

[JerryM]

Here's the Thread wherein Frank officially announced the Avastar preamp. https://www.audiocircle.com/index.php?topic=75951.0. Within the AVA main page, use the search box in the upper right hand corner to find more threads using the word Avastar. 

Have fun,

Jerry

[abernardi]

Thanks guys!

[Maceo23]

A fellow BEL owner!  I an AVA pre in my system years ago.  I liked the match as well. 

[avahifi]

The AvaStar hybrid preamp was and remains an outstanding musical performer.

It did have one issue:  Our clients who wanted a vacuum tube preamp really wanted one that was all tube and were suspect of the AvaStar, especially since the output current buffer used looked suspiciously like a little integrated circuit opamp.  It was not an opamp, just an amazing little current amplifier which was in the overall feedback loop providing very low output impedance and high current drive and increasing overall circuit linearity.

So we finally had to go back to replacing the LME49600 with a 12AU7 vacuum tube for the output current buffer to please potential clients.  This required a major redesign of course, but we have had excellent results with the Fet Valve CF and Fet Valve CFR all tube units since making this change.

For those still using an AvaStar preamp, we recommend replacing the line tubes (which now would be 6CG7 or 6N1P types) with 6922/E88CC types for improved sound and less heat.  We have the EH6922 tubes available at $35 a pair plus $10 shipping.

Frank

[Charles Calkins]

 
    Hi Guys:

              I have one. I've had it for 10 years. Never had to change tubes. It still has the original
              tubes it came with. As always when Frank builds something it is done right!!! Also built
              like a tank!!.
                                              Cheers
                                             Charlie

[abernardi]

This is great.  I'll look into the tube replacement Frank.  And Maceo23, nice to see another BEL user.  I know a guy who services these things, BTW if needed.

[yeldarb]

Frank, a friend just bought a used Ultra II, with 6CG7 tubes.  Are you saying he can use 6922 tubes with no modifications?

[avahifi]

We are using EH6922/6DJ8  tubes in the line sections of all our preamps that previously used 6CG7 or 6N1P tubes with superior results.

Besides having a more relaxed and engaging sound, they draw only half the heater current and thus let the preamps run cooler.  They also are shorter then the 6CG7 tubes so don’t interfere with the cover in some models.

Note that 12AX7 tubes are still required for the tube phono sections of all our older tube and hybrid preamps.

6922 tubes are not a substitute for 12AT7 tubes, incompatible heater voltage and gain.

Frank

[Tone Depth]

Frank,

Would the EH6922 tubes also provide an upgrade for the Vision Hybrid DAC using 6CG7 tubes?

Thanks

We are using EH6922/6DJ8  tubes in the line sections of all our preamps that previously used 6CG7 or 6N1P tubes with superior results.

Besides having a more relaxed and engaging sound, they draw only half the heater current and thus let the preamps run cooler.  They also are shorter then the 6CG7 tubes so don’t interfere with the cover in some models.

Note that 12AX7 tubes are still required for the tube phono sections of all our older tube and hybrid preamps.

6922 tubes are not a substitute for 12AT7 tubes, incompatible heater voltage and gain.

Frank

[avahifi]

Yes, the 6922 tube is an improvement in our previous generation DAC models that had 6CG7 tubes.

[I.Greyhound Fan]

Frank, can the 6922  tube be used in my older Ultra SL II DAC and Preamp?  Both used the 6N1P and had the upgrade to use the 6CG7's.

Thanks,

Larry

[avahifi]

Hi Larry,

Yes, you can try 6922 tubes in both the preamp and the DAC.

Frankly

[JerryM]

Gosh, I've been running Telefunken E88CCs in my T8 since 2010. 

… Changing the T8's 6N1P valves to 6CG7 valves  allowed quite a bit of upward rotation to the volume. The current iteration, with Telefunken E88CC valves, allows even more, with added separation and clarity to the music. ...