In the nov stereophile, there's a review by fremer on a 55k/pair amps designed by the whose who of audio -jc, j borngiorno, bascom king, Peter Madnick ... It's called the Centaur and apparently the younger brother of Hercules.
Nice looking amp, nice review and decent measurements.
What I didn't quite understand in the article was the technical blurb on the design where MF describes the technical bits. It's extracted and shown below - sounds a bit vague to me.
Another review of the amp's bigger sibling in TAS also had a similar description.
Is this a circlotron ? If not, then what sort of design is it ?
" The Centaur is a balanced design. So how, you ask, can a single-ended amplifier also be a fully balanced amp? Constellation calls its proprietary topology a Balanced Bridge design.
Instead of the usual push-pull arrangement of N-type output transistors for one half of the waveform and P-type devices for the other half (each of which has somewhat different performance characteristics), within each Centaur Mono are a pair of carefully matched “floating” (ie, not referenced to ground) amplifiers, both using only N-channel MOSFETs. (There are eight transistors on each half-bridge, for a total of 16.) One amplifier is fed the balanced signal’s negative phase, the other the positive. The speaker load directly connects the two amplifiers. The unique arrangement is similar but not identical to bridgeable stereo amplifiers that can be configured to produce more than double the power when used as a monoblock. "
Nice looking amp, nice review and decent measurements.
What I didn't quite understand in the article was the technical blurb on the design where MF describes the technical bits. It's extracted and shown below - sounds a bit vague to me.
Another review of the amp's bigger sibling in TAS also had a similar description.
Is this a circlotron ? If not, then what sort of design is it ?
" The Centaur is a balanced design. So how, you ask, can a single-ended amplifier also be a fully balanced amp? Constellation calls its proprietary topology a Balanced Bridge design.
Instead of the usual push-pull arrangement of N-type output transistors for one half of the waveform and P-type devices for the other half (each of which has somewhat different performance characteristics), within each Centaur Mono are a pair of carefully matched “floating” (ie, not referenced to ground) amplifiers, both using only N-channel MOSFETs. (There are eight transistors on each half-bridge, for a total of 16.) One amplifier is fed the balanced signal’s negative phase, the other the positive. The speaker load directly connects the two amplifiers. The unique arrangement is similar but not identical to bridgeable stereo amplifiers that can be configured to produce more than double the power when used as a monoblock. "
Last edited:
Taken at face value I would read into it this...
1) N and P types are bad because they are not mirror images of each other.
2) It uses eight pairs of outputs per channel.
3) The specific mention of " One amplifier is fed the balanced signal’s negative phase, the other the positive states clearly implies that the amplifier needs a balanced signal rather than a normal single ended (eg an RCA type) input.
In other words (according to the blurb) it is a "bridge amp" except that the phase splitting is done in the source component feeding it (the preamp) which must have balanced outputs.
1) N and P types are bad because they are not mirror images of each other.
2) It uses eight pairs of outputs per channel.
3) The specific mention of " One amplifier is fed the balanced signal’s negative phase, the other the positive states clearly implies that the amplifier needs a balanced signal rather than a normal single ended (eg an RCA type) input.
In other words (according to the blurb) it is a "bridge amp" except that the phase splitting is done in the source component feeding it (the preamp) which must have balanced outputs.
I do use SE balanced approach in my DIY amps, but there should be something wrong, with indicated output power 500W at 4 Ohms.
I x I x 4 = 500, I = 11 amps (RMS) into load, I idle = 15 A
For SE balanced I idle is two times larger, = 30 A
If one uses alef-kind or similar modulation of current source, then we again go down to 15 A. This is a kind of enormous idle current, hardly believable.
I understand SE stage as one rail power supply stage (and ground rail).
Don't 'over-speculate' guys. It is two push pull amps in bridge configuration. However the outputs are Nchannel Mosfets driven with a circuit that makes them push pull. It was put to me, conceptually, by the designer of the amp about 40 years ago. This is the first successful implementation of this design approach that I have ever heard of.
Yes, John, I was almost sure that they have used an advertising trick, saying SE balanced, but having in fact push-pull balanced. The last approach does not fall in a cathegory of current consumption from PS that is independent on the output signal. Because of this, one could become a DIYer, in order to have taste of a "proper concept". Industry can not help us in this sometimes, too low wattage, low customer demand.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.