http://pbnaudio.com/audio-components/audio-amplifiers/olympia-ebsa-3
and its two smaller siblings :-)
Good Listening
Peter
and its two smaller siblings :-)
Good Listening
Peter
Full-sounding SS amps (besides Pass)
Speaker interactions aside, what solid state amp brands/designers tend to have a fuller sound these days? Not necessarily warm or tubey per se, but fleshed out in the upper bass and harmonically complete in the midrange, as opposed to lean. E.g. an Australian ME Sound amp I have from a while back has this quality, without sounding overtly warm.
Obvious candidates: Pass, Luxman. What else?
Cost no object, feel free to throw out one-liners. Think of it as a poll. (Please don't answer tubes though, thanks. :D )
Obvious candidates: Pass, Luxman. What else?
Cost no object, feel free to throw out one-liners. Think of it as a poll. (Please don't answer tubes though, thanks. :D )
Showing 3 responses by pbnaudio
Mitch, Pass use Hexfet in the output stages, namely the IRF240/9240 (TO247) these are more of an industrial transistor then one designed specifically for Audio. If one pairs many of them in parallel in an output stage it becomes necessary to use source resistors to make them share current properly, if not one device will hog all the current and self destruct. In our entry-level Liberty Audio B2B-100 I too use HexFet, the IRF630/9630 (TO220) industrial devices too and they need Source Resistors too to play well together as well. http://www.libertyaudio.com/products/b2b-100-all-mos-fet-stereo-power-amplifier These types of HexFet need a lot of Bias current to sound good. Toshiba and Hitachi/Renseas make some Mosfet specifically designed for Audio, in our earlier series of Amplifiers I used the Toshiba J200/K1529 in the current series of amplifiers I use the modern day equivalent of the J50/K135 lateral MosFets made by Exicon 10N20/10P20 (TO3) these are made specifically for Audio - Renesas makes the same type MOSFET J162/K1058 (TO3P) These have a softer sound than the Industrial type Mosfet mentioned above, you don’t have to run quite as much bias current to make them sing, and if you match them close there no need for Source Resistors to make the share current. I prefer the sound of MOSFET output stages - to my ears Bipolar always produce a "lisp" "s" kind of sound. As with anything its in the execution of the design - Pass makes excellent amplifiers with the HexFet’s Good Listening Peter |
Mitch, The amplifiers are designed to be dedicated mono blocks and most use them as such, there is just the convenience that you can run one as a stereo amplifier. The idea was way back when we started making Amplifiers (1998) that the customer could start with one amp then later get a second one. The offerings back then were the Whitney, Denali and Everest with the Companion K2 preamplifier. These could be driven in "bridged" mode as you call it - where the inverting amplifier (with positive input grounded) is driven by the negative side of the non inverting amplifier. However sound quality improved when driven balanced with a fully balanced preamplifier like the K2. The newer series of amplifiers, (which started with the Mini Olympia, ca 2004) is based upon our ALL-FET circuit which needs both nodes driven when using as a mono block - i.e the inverting amplifiers positive input needs signal. So a balanced input signal is required. We only make fully balanced preamplifiers, even in the Liberty Lineup. The power output quadruple when using them as mono blocks, obviously the output impedance will be twice that of a single channel but since we don't use any source resistors because of tightly matched output devices, the output impedance is vanishingly low. Most all our customers use our amplifiers a dedicated mono blocks, everything improves, coherence, speed, dynamics both micro and macro. Good Listening Peter |