"How about those pre's; are they Class A (or doesn't that matter anymore)?
Reply With Quote"
They don't mention that so I can assume not.
the last word from Rupert Neve
IS IT “CLASS A”?
What is “Class A”? It’s not just an expression of “goodness” that has been used carelessly to describe every kind of amplifier from consumer electronics to Pro Audio. Class A is actually a mode of operation in which the supply current to the amplifying device does not vary as a function of the amplitude of the signal being amplified.
Efficiency of Class A amplifiers is low, but the wonderful sound of my old consoles was achieved with single sided pure Class A amplifiers. In those days console features, facilities, tracks, Aux's etc. were far fewer and we could pack these large, heat generating circuits into the module.
The ever increasing complexity of modern Sound Control Consoles led to the widespread use of Integrated Circuits (I.C.s) to save space and achieve better efficiency. I.C.s are almost all push-pull amplifiers that have some residual crossover distortion. Some have very low distortion but even when this is well below the noise level, it can influence the sound we hear.
Humans can detect incredibly small values of this type of high order distortion. It’s not heard as such but causes emotional feelings of dissatisfaction and fatigue. The only way to totally eliminate crossover distortion is to use a Class A single sided amplifier. This can only be achieved using discrete components. The efficiency is low but the sonic advantage has been proven over many years.
Portico™ modules are very carefully configured to be as simple as possible, but sonic integrity has been given the highest priority. The low efficiency of these discrete circuits is reflected by the high supply current required by Portico™ modules!
ANyhow back to the subject, I like these pre-amps and bought them on the advise
of a studio owner who has Matched Avalons, 430 ISA'a, Manley, and Blue RObbie and
a UA 6176. Which BTW, I have the UA6176 in my possession.
using
the UA 6176 against the onyx with Wave Channel Plug while tracking to disk, I
prefer the Onyx and Renn. ( less trouble plus gating) same big sound with only 5ms delay monitoring.
Pre-to pre I found the 610B just a hair softer in hi-eq ( on my passive Tannoys )
on vox and bass direct testing. These where very subtle differences so after I buy everything else maybe I would get a 610 SOLO for the the way it softens the sylibis
on a condensor mic.
Again, I took a layer of "wax paper" off in clearity of sound just going 400F and ditching the M-audio 24/96 and delta 44. 400F is the clock.
embeded clocks can be bypassed and you only want one ( your most stable clock) and everything else slaved to it. Ie M-audio will sound better if you go so far by an Apogee clock and slave it Via "Word."
If you get it let me know the diff. in 2 610 B and Grace 101 to onyx
I did not find I could bypass the pre-amp 1-4 onyx( the pre nobs are active and add
gain). I could not find a way to bypass them even with a half insert on the insert channels.
