Amp Modelling: Bob Carver & Transfer Function Amps
I heard some guitar amp modelling the other day & was quite surprised at how it's possible to cheaply create a convincing facsimile of a range of different classic amps from a single device.
This brought back memories of the saga of Bob Carver and his Transfer Function Amps of the mid-80's, so I did some web trawling to read a little more on the subject.
For those who know nothing of this, I'll re-tell the story as I understand it:
Carver challenged two audio magazines to select an amplifier for him to test from any maker and price level & he would then make small modifications to one of his own designs and the staff of the magazine would be subjected to a listening test where they would try to distinguish one amp from the other. Carver's amp was quite cheap & he was willing to put it up against anything.
The first magazine to take him up on his challenge was The Audio Critic and they offered a pair of Mark Levinson ML2's. He was successful in matching the sound and no differences could be discerned.
Next up was Stereophile magazine, who supplied the Conrad Johnson Premier 5, a $12K power amp and added the condition that Carver reproduce it's sound within 48 hours. Stereophile were extremely confident that they could easily reveal the difference between the two amps, especially as the testing was to take place in their own premises & with their own ancilliary equipment.
"After the second day of listening to his final design, we threw in the towel and conceded Bob the bout."
"We had thrown some of the most revealing tests that we know of at both amps, and they came through identically. Even on the subliminal level--the level at which you gradually get the feeling that one amplifier is more "comfortable" than another--we failed to sense a difference between the two amps."
"We wanted Bob to fail. We wanted to hear a difference. Among other things, it would have reassured us that our ears really are among the best in the business."
"According to the rules of the game, Bob had won."
"The implications of all this are disquieting, to say the least. If, after only four days of work, it is possible for someone--design genius or not--to make a $700 amplifier sound exactly like a state-of-the-art amplifier costing many times as much, what does that say for the cost-effectiveness of the latter?"
Carver later marketed the $600-700 M1.5t which was supposed to sound like the amps in the challenge and was compared to $4K – 5K models. Later, he produced the Silver Seven, a hugely expensive (10's of thousands of dollars) valve design. In order to prove how he could still model amps, he modelled the Silver Seven with a £600 model, the M 4t Magnetic Field amp. All were, apparently hugely unreliable and the modelled amps needed constant adjustments to keep them sounding like the amps they were supposed to be cloning.
Then there was an exchange of lawsuits between him & Stereophile, where he claimed they were discrediting him, despite admitting to losing the challenge & they sued for his unauthorised use of their copyright.
I seem to remember loving the looks of the both Silver Seven (especially it's power supply) & the M 4t, from photos – never saw them in the flesh.
http://www.wardsweb.org/audio/carver_images/silver7.jpg
Images here:
http://www.wardsweb.org/audio/carver_info.html
So, what I'd like to know is this:
Has anyone on AoS heard any of these machines, or do they know anyone who has?
Did they sound any good?
Did they really do what he said they would?
Is there any more to the story than I remember / have just read?
