Paul McGowan said: Yes, we should be able to keep it in the $5K range if I don't get too carried away.
Paul McGowan said: Output power will be a minimum of 200/8 400/4.
@frode He, he, he. 
Well, no. But here’s my internal goal. I want to take a prototype to the Munich show. We’re playing the big Raidhos in our room and we need something awesome. Wish me luck.
Paul McGowan said: Stereo. I know there may be some appeal to having to giant monoblocks but technically, other than separate AC inlets, there would be no advantage.
There is another one - with monoblocks you can have very short speaker cables and 2-3m balanced interconnects.
Hint Hint.
What if you could deliver Class-A power flow in Class-B mode and without caps?
Yes I am from another planet, but please think about it.
Ah, but that would then make it Class-?.
>:)
Paul, I'm interested to know if the new amplifier(s) will be designed with certain specification goals. Personally I think current delivery is a useful specification, but most people go with power into an 8 ohm load. What is your target?
Or is the target just to make it sound great and disregard the specifications?
Aside for the obvious specs such as power, distortion and noise, the several that I will be focusing on are bandwidth, open loop stability and output impedance (current delivery). All these are critical factors in an amp. But bandwidth has become a real center piece for me. The amp I am listening to now is flat to 100kHz.
stereophilus said: You are an elite "agent provocateur" Gordon. I think you need to be more specific as your suggestion of class A and class B in this context mean nothing to me.
I understand that you are driving speculation here, but let's stick to the facts.
Paul McGowan said: Well, that's true, but I doubt I am going to be able to put anything in the P10 box for less than $4k retail and probably closer to $5k so that means we're $8K to $10K for separate monoblocks when we could have the same thing for $5K in a single P10 chassis. Maybe I am just a cheap son of a bitch, but it seems to me that's a lot of money to pay to have a shorter length of speaker cable.
Perhaps there can be a compromise here.
How about “dual-mono” amp in one box and dual power supplies?
Unless you go to switching supplies and then it might even fit in the DS box?
Gordon said: How about "dual-mono" amp in one box and dual power supplies?
EDIT: dual EXTERNAL power supplies. [ if linear]
Perhaps there can be a compromise here.
How about "dual-mono" amp in one box and dual power supplies?
Unless you go to switching supplies and then it might even fit in the DS box?
Actually, guys, it’s partially my fault this is dragging on so long.
The first input stage didn’t work out as well as Paul had hoped.
So last Fall I went to Boulder and showed Paul the schematic from my tube preamp I had managed to get that had no feedback. Very simple circuit, sounded great. But it used tubes. Capacitor coupled. Paul had been toying with no feedback and this had clinched it for him, hence the new input stage. (The new circuit is basically a solid-state version of a tube gain circuit with MOSFETs instead of vacuum) At the time I had no idea he and Ted were working on DirectStream. I thought, hey, marry the new stage to the Hypex and we’re done.
The rest, of course, is history as the Hypex were Overtaken By Events (OBE)
So hopefully this won’t take another 5 years (which is how long I’ve been waiting for a new amp)
Right now I can only sit on the sidelines and watch, as there’s not much else I can do to help other than to root for the team. Let’s hope Bascom’s output stage marries well to Paul’s input stage.
Only thing we can do is wait and see. Unless, Paul, there’s something else you want us to do?
–SSW
When PSA was selling the original PowerPlants (P300, P600 and P1200), Paul announced that they would be building a series of amps based on the same topology. I was so impressed with my P300 (which is still an amazing piece of equipment) that I decided to wait even though I had been in the market for a new amp. Two years later PSA released the Classic 250. It’s topology was completely different from that of the PowerPlants, although it did have a built-in regenerator for the input board. I bought it and it sounded, and still sounds, great. My point is that Paul has a way of zigging and zagging that can be a bit frustrating to consumers because of the resulting delays and direction changes but in the end the result is something really special. (The frustration is the price we pay for having an open and ongoing discussion about his thinking and what he is working on.) Like Streets, I’ve been waiting for the new amp for a long time (there is a home for the Classic 250 in my second system, if it continues to work that long). I’ll continue to wait because I know the new amp will be killer.
Yikes!
Another review to do? :-SS
Anyone know of any MFGs using feedforward?
@gordon - I realize that you may have been only joking, but I am aware of another company that uses a patented feed-forward circuit in their solid state power amplifier designs. I am not sure if it would be appropriate to mention that company’s name here, but will do so if I get approval from the PSA powers that be…
@audio.bill
No joking.
I have been hearing about successes with class-h for a few years now and have heard my friends prototypes that were amazing. Class A performance but with low [ B-type] heat and consumption]
I’m making noise about this since Paul is reworking the Amp project.
I’ll continue to do so till told to shut up.
It opens new potential and worlds for future designs.
There is a Brand launching this Spring and I am for sure going to audition it.
I have a question. If amps are really supposed to be transparent but of course non really are. Wouldent the goal be just that at any cost for Paul. As the worlds best Amp is a tall enough order I am thinking . And Paul already blew the bank on this already . So as I hear your thoughts gorden , I would think good proven design concepts are in order. But of course with the nessaserry improvements to achieve Paul’s new bar height.
Gordon please do not take offense with my view , it’s just my useless point of view LOL
AL
@gordon - Class H amplifier designs have been around for many years, and they basically utilize a power supply with variable voltage rails modulated by the signal. Their main advantage is in efficiency gain and therefore the ability to use smaller heat sinks. Class H designs do not maintain Class A performance of the output stage unless there is some other type of technology in play. The feed-forward design I was referring to is not a Class H design.
Sure they have been around.
What is newer are the controllers for switching power supplies and the reduced interference.
From what I understand class-A power is available through a canceling out system that provides the efficiency and the heat reduction.
I am not a tech but will see if I can dig up a recent doc.
@gordon - I realize that you may have been only joking, but I am aware of another company that uses a patented feed-forward circuit in their solid state power amplifier designs. I am not sure if it would be appropriate to mention that company's name here, but will do so if I get approval from the PSA powers that be...
Hegel Music Systems uses their patented SoundEngine technology which makes the use of “local and adaptive feed forward technology”. They claim that it cancels crossover distortion and achieves the advantage of Class A designs without their drawback of low efficiency. Further details can be seen on their website: http://www.hegel.com/technology/soundengine-technology.