[avahifi]

This is indeed an AVA preamp built in a Hafler DH-100 chassis.  I could not tell you more without seeing inside it. I can tell you it is old, probably 25 years old or thereabouts.

Arthur, your first Hafler preamp was probably the earlier model DH-101.  That one had dual concentric volume and balance knobs and two rows of rectangular push-button switches.  The DH-100 came later.

I don't remember doing a "dual mono" circuit in a DH-100.  I suspect it has a stereo line board and a stereo phono board, or possibly just a power supply board and a stereo line board.  Again, I can't be sure without internal (and much sharper) photos.

Frank Van Alstine

[mark funk]

http://www.ebay.com/itm/Dynaco-416-Power-Amplifier-Modified-Stereo-400-Van-Alstine-W-Manual-Documents-/190873555487?ssPageName=ADME:B:SS:US:1120



                                                                                                                                 

[avahifi]

This one is badly misrepresented by the seller!  Avoid it!

The seller says to read down to learn all about it.  When you do, as I did, you will notice that this was a simple driver board do it yourself kit we sold to the original owner in 1978 for $100.00.

Since is was a kit built unit, not done in our shop by our technicians, we have no way of knowing if it was properly built or not.

Fuses?  The seller says it does not need fuses!  Wrong!  Never fuse an old Dyna 400, with our circuits or not, with more than 5 amp quick blow front panel speaker fuses.

I don't have an e-bay account.  If someone here does, I would appreciate it if they would contact the e-bay seller and tell them to read down to the original receipt for the kit and then change the description of the product to reflect the truth.

Frank Van Alstine

[mark funk]

Yes I know this is old but it has some pics of the insides,


http://www.ebay.com/itm/VAN-ALSTINE-MODEL-TWO-POWER-AMP-/251317857290?ssPageName=ADME:B:SS:US:1120



                                                                                                                       

[avahifi]

This amp was built by VA Systems about the time I left that company.  I was promised service data on all models and that my name come off their products.  Neither of these actions ever happened.  VA Systems folded up soon thereafter.

I have no service data or parts for any old VA Systems product so I cannot economically repair them.

Frank Van Alstine

[Toni Rambold]

Nice pics with the old 16 amp transistors on both channels -
but the thermal sensor which switches fan (hi-lo)speed at
63°C/140°F is missing - and air cooling for the Model Two is crucial.

 

[mark funk]

just in from Ebay , we have seen this here on the Circle,


http://www.ebay.com/itm/Audio-by-Van-Alstine-Ultra-550-Amplifier-/190888946006?ssPageName=ADME:B:SS:US:3160

                                                                                                                   

[mark funk]

This looks real clean!

http://www.ebay.com/itm/DYNACO-Audio-By-Van-Alstine-Super-Pass-Two-preamplifier-/171149436468?ssPageName=ADME:B:SS:US:1120


                                                                                                                       

[rkeir]

This looks real clean!

http://www.ebay.com/itm/DYNACO-Audio-By-Van-Alstine-Super-Pass-Two-preamplifier-/171149436468?ssPageName=ADME:B:SS:US:1120


                                                                                                                       

It has at least two of the three options available back then: the faceplate and the switchcraft jack set. The third option was the GE 5751 tube set. Impossible to tell from the photos if it has those tubes. I have one just like it that I purchased in 1987, except I sent mine in to be upgraded to a "3" sometime in the 1990's. Nice preamp.

[avahifi]

Actually GE 5751 tubes were our standard tubes way back then because we could not find decent 12AX7 tubes at a reasonable price then.  This is before many good 12AX7 tubes reappeared.

The 5751 tube is a low gain version of the 12AX7 and actually would not be recommended today, especially for the phono section where as high a gain as possible 12AX7 tube is needed.

Frank VA

[etcarroll]

Having just moved from a re-capped Bryston 4B to a supercharged Hafler xl-280, I'm thinking a tube/mosfet hybrid is where I want to be. I would love to find a piece like this 550 that could be upgraded to a 600. 

just in from Ebay , we have seen this here on the Circle,


http://www.ebay.com/itm/Audio-by-Van-Alstine-Ultra-550-Amplifier-/190888946006?ssPageName=ADME:B:SS:US:3160

                                                                                                                   

[mark funk]

Look at this thing,

http://www.ebay.com/itm/Designer-Van-Alstine-Dynaco-PAT-4-Pre-Amplifier-or-Amplifier-/291005016078?ssPageName=ADME:B:SS:US:1120



                                                                                                                           

[dB Cooper]

Wow, I didn't know there was a way to make a PAT-4 uglier than stock. Something tells me that that isn't how it looked when it left Frank's place.

[avahifi]

This is a very old (like 30 plus years old) Super Fet Pat-4 without a faceplate.  It never went out of our shop that way.  They were ugly enough even with a stock faceplate.

There is an original PAT-4 faceplate for sale separately in an additional listing below the preamp listing!

One would still need to find the original knobs though.

Note that the tone controls and their circuits are missing.

Oh well.

Frank Van Alstine

[mark funk]

I don't know?

http://www.ebay.com/itm/Dynaco-ST-120-Completely-rebuilt-with-Van-Alstine-Designed-Power-Supply-Dyna-120-/141173193529?ssPageName=ADME:B:SS:US:1120


                                                                                                                             

[avahifi]

This very old Dyna St-120 does not look "completely rebuilt" to me.  It has all of the original old old old power supply capacitors, a bunch of non-standard transistors on the audio boards, lots of very sloppy wiring work, and there is no photo of the power supply section to tell what it is, or is not.

Not my idea of a great deal.

Frank Van Alstine

[etcarroll]

Is there any background on this unit?

http://www.ebay.com/itm/Van-alstine-MosFet-240D-amplifier-/161208631248?pt=US_Home_Audio_Amplifiers_Preamps&hash=item2588c87fd0

[avahifi]

I can't find any customer records of refurbishing or repairing a Mos-Fet 240D here since 2007.  I also notice the AVA back panel label with serial number appears to be missing.

Just questions to ask the seller before buying.

This is a 120W ch amplifier about 15 - 20 years old and is a nice sounding unit if still in good condition.

Frank Van Alstine

[etcarroll]

Just sold a refurbished Bryston 4B and looking for something with a bit more than 120 watts. For now using a Hafler xl-280 with upgraded power supply, I like the sound with mosfets, looking to go tube/mosfet hybrid.

[avahifi]

We just acquired, tested, and upgraded an original AVA Transcendence Two 140W/Ch power amp built into a very nice black Hafler DH-200 chassis.

This was a very special amplifier, all solid state, all mosfet, and very tube sounding.  It is lovely sounding and in very nice condition.  There are no Hafler circuits, it is all AVA with VERY sophisticated audio circuits that we eventually discontinued because they were just too expensive to build and some of the active devices needed were discontinued.

Fortunately much better than new devices have become available now and with this amp resurrected with all new Exicon power mosfets, both in the output and line circuits, it is now better then new.

We need to get $595 for this gem with a one year AVA parts and labor warranty and a 30 day satisfaction guarantee.

Frank Van Alstine