atmasphere
Active member
We'll be building our next production in November.
Power amplifiers that excel with very low impedance - and low efficiency loads
- Thread starter Jim Smith
- Start date
We'll be building our next production in November.
BayStBroker
New member
- Joined
- Jan 15, 2015
- Messages
- 292
This week, partly for amusement, partly because I got a good price, I bought a pair of M700 PS Audio class D amps on the used market. We have a kitten in the house and the Parasound JC 1+ run hot as hell (all class-A for first 25 watts). No cat can resist sleeping on them. And the Parasounds don't sound good unless they've been on for a couple of hours. Being unable to ensure constant surveillance, I was in a bind. In fact, I am totally enjoying the M700s. They drive my Magic S3 Mk2 speakers very well. Paul McGowan and designer Darren Myers made quite an elaborate project of making the most of the ICE power module they used. It is very deliberately "voiced" to sound agreeably audiophile. Detail and imaging are abundant and they added a touch of musicality in addition to giving the midrange an obvious boost. The result is less a novelty than the audio equivalent of a perfect gourmet burger (wagyu beef and blue cheese included). I'm relieved to have something I can use with real pleasure during the week when I don't have time to heat up the Parsounds, and in summer when my air conditioning cannot keep up. They slide right into my system with the Aesthetic preamp and Lampizator DAC and give very clear voicing to the specific personalities of each. I am tempted to say that every audiophile should have a good class D amp kicking around for times when quick and cool are required qualities in an amp.
a.wayne
Well-known member
Over a 100deg , must be Global warming Central and For clarity , Ralph had told me he is doing a class D 7-8 yrs ago ..
a.wayne
Well-known member
Tried too many to keep count , not for me , cant get over their bad timbre , i do hear great things about Belcanto black and Merrill thou ..!
Regards
Dizzie
Well-known member
Over a 100deg , must be Global warming Central and For clarity , Ralph had told me he is doing a class D 7-8 yrs ago ..
Are you saying I should exhale? i.e. Not hold my breath.
atmasphere
Active member
Ralph had told me he is doing a class D 7-8 yrs ago ..
This statement is incorrect. Our first work started more like 4 years ago and prior to that we had not discussed with anyone outside the company anything with regard to making a class D.
BayStBroker
New member
- Joined
- Jan 15, 2015
- Messages
- 292
I take your point but I can find no meaningful fault with timbre from the PS Audio M700s. Listening to piano right now and all is very good. If you want anyone to "voice" the ICE module to sound maximum audiophile, Paul McGowan would the one the to choose. Justice is being done to my excellent sources and to my speakers. The M700 is just $3300. I admit I get a kick from the value. I also admit I wouldn't want to be confined to only class D. The Magico's come alive more fully when I use the JC 1+s. But given the feline problems and summertime heat problems I am happy to have these amps in rotation.
Puma Cat
Well-known member
Wow, this thread has taken such a digression from the subject of Jim's original post, maybe all the amp "techical side-bar dicussion" should be moved to it's own thread. Lots of good info here, but pretty far from JIm's original post.
Jim: I'd go with Constellation if it's in your customers budget. Just sayin'....
'
Jim: I'd go with Constellation if it's in your customers budget. Just sayin'....
'
Randy Myers
Well-known member
Not sure this qualifies, but here is the NAD C 298 specs:
Rated output power into 8 Ohms (Stereo) 185 W at 8 ohms (ref. 20 Hz-20 kHz at rated THD, both channels driven)
Rated output power into 4 ohms (Stereo) 340 W at 4 ohms (ref. 20 Hz-20 kHz at rated THD, both channels driven)
Rated output power into 8 Ohms (Bridge mode) 620 W at 8 ohms (ref. 20 Hz-20 kHz at rated THD, both channels driven)
THD (20 Hz – 20 kHz) <0.005 % (1 W to 185 W, 8 ohms and 4 ohms)
Sure looks like they claim same low distortion for both 8 and 4 ohm. Am I missing something or are they claiming that the distortion figures do not raise at 4 ohm?
a.wayne
Well-known member
Your memory fails you, we have had this and that discussion maybe 100 times already ....
a.wayne
Well-known member
A dollah for every AS member complaint and suggested sanctions and we could have bought constellation mono’s by now ...
:roflmao:
Let it flow
Regards
atmasphere
Active member
Dunno! But it would be interesting to see how it actually behaves. The amp doesn't double power- in sufficient heat sinks or power supply?? With a limitation like that imposed I would expect to see it affect distortion too.
This statement is false.
a.wayne
Well-known member
No Ralph your response is , not calling you out just saying your memory maybe failing you...
Regards
Regards
a.wayne
Well-known member
Its just numbers playing Randy , all part of the modern marketing scheme, find the lowest distortion rating into 4 ohm and rate the 8 ohm power at the same distortion number ..
Very similar to the ridiculous “ pure class A power” mantra of late ...
Regards
u-sound
Active member
i think we are ok continuing the thread this way since jim (i think) is no more in search.
the client has a speaker with a nasty load. what can he do?
well, sell the speaker or buy an amp that can handle the load.
however, the client (if i understood correct) wanted to buy an amp on top to the existing one and drive the bass separately.
to make that sound good, you will need an extra crossover that will be capable of adjusting phase etc, you will need more cables and actually the SAME amp you already have.
so if your first amp cant handle the load why buy it again.
bottom line, if you do it right, it will be very expensive.
Randy Myers
Well-known member
Its just numbers playing Randy , all part of the modern marketing scheme, find the lowest distortion rating into 4 ohm and rate the 8 ohm power at the same distortion number ..
Very similar to the ridiculous “ pure class A power” mantra of late ...
Regards
Maybe, probably true... but still the distortion figure it pretty darn good. Can't really complain about a <0.005%... of course I am not a numbers guy any way. What intrigues me is the discussion talking about how good the Purifi amplifiers sound.
atmasphere
Active member
It isn't. Your use of hyperbole is failing you however. '100's of times?? Nope. Eight years ago we had no plans of a class D amp. None. That didn't happen until about 4 years ago. So how could I have talked to anyone about the project eight years ago?? The answer is simple: I didn't. In fact I kept silent about the class D project for about a year.
So please cease and desist about attacking me regarding the state of my memory. Reporting your post as the abuse that it is failed to get any response out of the moderation team (and being a moderator on another site I know the definition of abuse) so I'm simply stating here how to deal with this: if you disagree with someone on a topic, attack the post, not the poster. Get it??
stereogeek
Member
- Joined
- Mar 15, 2018
- Messages
- 472
If a person is going argue with Ralph about amplifiers I have just one suggestion for that person. Do not enter into a battle of wits unarmed.
a.wayne
Well-known member
Ralph,
I have been on the brakes very hard with you over this , you are the one doing the personal attacks , I’m only responding to your attacking rants ..
We have had many audio discussions over the years , most recently at the fla audio show in 2020, in your room, as well as numerous other times over the years in many different forums. In forums its your usual strawman arguments basically to support your limited power high impedance only driving amplfiers of choice, now I'm not going to use my time to search the WWW to prove any and everything about your class D amp rant , i don't care , But to say never Outside your company until recently is a joke Ralph, I’m guessing to protect your patent, well for the record no details were ever disclosed , you only mentioned in discussion you were looking into a class D design, it was some years ago ..
Here are a few mentions by others Of (going back a few years, first pic 2018 easily found) your no discussion until recently class D amps,
is 2018 recently Ralph ..?
We have had these and many discussions over the decades Ralph, so if not 7 or 8 on your class D ,maybe 5 ? it was some years back, again you mentioned you were looking into it and that it looked very promising, there were also discussions over your Vinyl cutting/ pressing issues , how backed up you were , how stereophile wouldn't give you a review, discussions on NFB, why OTL , why toob amps with transformers are bad , many this or that , blah , blah, blah ..!
So Please ...!!!
Strangely after bashing SS amps for decades here you are promoting Class D, is this because you now have commercial interest ? is anti NFB Ralph now pro feedback Ralph, bet yours is the greatest and sweetest kind of NFB...
No wait zero feedback class D ..!!
Is degeneration feedback? ...
Maybe ignore is best and give the mods some rest...!
Regards
PS : Congrats on the patent
