[turkey]

I am not trying to be smart, but I guess my question was, and still is:

What is the difference between the first generation Ultimate 70 circuit, and the Ultimate 70 upgrade circuit? Now that I know that they both can be mounted above the chassis in DIY kit form.

I've really tried hard to make my question clear.

They're the same thing. There is only one Ultimate 70 circuit for use in a stock-type ST-70 chassis.

[Wayner]

Those drawings are property of AVA.

Wayner

[oneinthepipe]

.

[Listens2tubes]

Those drawings are my drawings. They are property of AVA.

Wayne

Cool Wayne, I will take a closer look the next time I get a chance.

Of coarse I personally meant my wishes for my MkIV's though they could pertain to any of the Dynaco tube amps. I wouldn't expect that Frank would consider making Ultimate Mark IV mono amps but how about Mark III's? Don't mind me I just like dual mono with no sharing.

[turkey]

Mark III's? Don't mind me I just like dual mono with no sharing.

This always makes me chuckle, because people want dual mono amps for good channel separation, and then they prefer vinyl, which has inferior channel separation compared to CD, and basically negates the advantage of a dual mono setup.

[Wayner]

Some folks go dual mono in bridged mode for increased power output.

Wayner 

[boycephoto]

I would be all over an AVA Ultimate Dyna MKIII.  Sure I am dreaming.  The Mark III was the first tube amp that Frank modified for me in 1979 or maybe 1980.  Before he decided to focus exclusively on the ST70.  I don't know what kind of response it would bring but....  I would be the first in line.     I have used 4 - modified Mark III's and my OmegaStar EC with internal phase inverter for a long time and really like the combination.

I am looking forward to AKFest 09 and hopefully seeing the new AVA Ultimate 70 chassis. 


Happy Easter,
Dave

[turkey]

Some folks go dual mono in bridged mode for increased power output.

True, but not very likely with the need for 4 mono amps to make up 2 bridged amps. Plus, most bridged amps don't sound very good IMO. (Which is why Frank has been building phase inverters for a while now - maybe since the FET Three Plus?)


Later: Ok, I just read boycephoto's post and I guess there _are_ people with 4 mono amps bridged down to 2 mono amps.

[Wayner]

Turkey,

No, that wouldn't be my idea of a good thing, but the phase inverter on 2 Ultimate 70's could be very "Ultimate" IMHO. I'm guessing about 70 WPC? That's lots of tube power, and would sound real sweet on my Dynacos.

Wayner

[Listens2tubes]

Turkey,

I'm guessing about 70 WPC? That's lots of tube power, and would sound real sweet on my Dynacos.

Wayner

Exactly my thinking. That would be why a MkIII with 60 watts would be a natural progression. Otherwise I'd buy the Ultimate MkIV kit and be done with it. aa

[avahifi]

Unfortunately the MK III is not a good candidate for upgrade for several reasons.

First it need 600V rated parts and those are expensive and scarce.

Second the output transformers are too big and inductive for great high frequency performance.  The output transformers are too small and saturate to easily for good low frequency performance.

Third there is not enough real estate available for the multiple regulated power supply circuits it would need (the MK IV has this same limitation) and again, the voltages required would be too high to do with existing parts.

We will pass on this one.  The ST-70 is a vastly better engineering compromise in the first place.

Regards,

Frank Van Alstine