John Curl's Blowtorch preamplifier part II

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A new 750 does $45K here, used ones go under 20
(gets even worse when the 750PSU unit is included. one might think coils are a bad investment)

I see 3 inductors, 3 ICs (two with heatsinks as mentioned), two relays, and a bunch of R and C. This does not look like it could be all that wideband as is alleged.

I'm pretty sure it sounds o.k. :) Price is steep.
 
I must say, that no matter if we find more to this unit, it is OVERPRICED! Now, how can I say this? I make stuff equally or even more costly, so who am I to agree with the rest of you?
Well, look at it, count the parts, the build quality, etc.etc. It just isn't there. Parasound sells something nearly equal in chassis construction and certainly in parts quality for $2300, so this phono stage appears to be priced about 5 times over its general worth in the marketplace. It is unfortunate when this happens, but it does.
It is like when, decades ago, GM 'tarted' up a Chevy chassis and called it a Cadillac. People, knowing that Cad's used to be a completely different, better design, revolted, as they well should have, and GM dropped their attempt.
I hope people will see through this attempt to overcharge the public with a 'cheap to make' component.
 
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Well you're doing something wrong, those guys are laughing all the way to the bank rolling IC's. Costs a lot more than the BT and looks like a lot less work and TAS thinks it kicks butt.

I thought the exact same thing.

That must come in one hell of an enclosure.

Not totally surprising though. You can tell people what they hear. You can spoon-feed them hyperbole, group think and manufactured concensus and they'll buy it.
 
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I don't think we could 'improve' the JC-1 that much to make it sell for $25,000, but I could design something that could. And LOOK at what you get with a JC-1, the quality of the components, (no IC's in the audio path), the fit and finish, as well as the heat sink area. And we ONLY charge $9000 a pair, '-).
 
I see 3 inductors

The inductors are also in each of the input stages after the three inputs, so six times total for stereo, part CM types.
The Burr Brown without a heatsink could be a servo.

(the coil addition referred to both the number of inductors, plus the ample use of Hamlin reed & NAIS relays, plenty of the both of them residing under the 720 boards i posted )

A Boulder 2008 costs more, in TAS's view also kick's butz, but after a decade they likely needed something new for them to not look old :clown:

btw : the 720 phono boards are used in both the 720 preamp and the 750 phono stage. At $25K/€34.9K retail i'd expected at least a separate batch with 750 print.
 
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I see I lifted the wrong spec for slew rate: it's claimed as 400V/ns for the phono preamp (330V/ns was for the power amp). I would also suppose from the specifications in Valin's text that the cited 100dB S/N ratio is with the input shorted. I'd like to know what it measures open.

So, are there enough reed relays in other parts of the circuit to make them the plausible switches for gain control?
 
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