Non class D SS amps

Mike Arnopol · #1 09-19-2011, 12:06 PM

I've been a big devotee of the new class d amps for the past 5 years. I'm not a tube guy. More vintage SS thump and punch with hopefully a more modern clarity.I love my EA stuff (I'm an endorser and was involved with the design of the Doubler) but as a 50/50 doubler I'm beginning to see the limitations (at least for me ) of the digital stuff when pushed to higher volumes with electric bass. Got out my trusty 70's IVP preamp (first to use the bass, 4 bands semi parametric, and treble control format) and my many bigass SS power amps. Nothing that I would carry around anymore. (4 rack spaces---40 lbs.) Plugged into my Thunderchild, and then an EA CXL 12 cab. Huge difference in tautness and control. So---in terms of amps in that ilk---20 to 25#ish--- I know of Thunderbass and now (upcoming ) Roger Baer amp. Any other ideas?

KJung · #2 09-19-2011, 12:18 PM

My guess is you are hearing preamp voicing more than anything else, especially with those small cabs that cab be driven to full performance with only a moderate amount of watts.

There is little difference in performance and max volume between similarly powered class D/SMPS heads and, for example, the Thunderfunk TF550B or TF750A.

That being said, the Markbass LMII/III is a class A/B power amp, and sounds wonderful, but is still micro in size.

I would again not really limit yourself to a certain amp topography. The micro's all sound SO different, from the HUGE low end of the Genz Streamliner, to the aggressive grind and punch of the GK MB series, to the warm but neutral voicing of the Markbass heads, the hi fi clarity of the TecAmp Puma's, etc., etc.

You might want to try the new Epifani 501. I'm not a big fan of that company any more, but that is also a class A/B micro and, from my experience with the 502, should be big, big, big down low (for better or worse).

shwashwa · #3 02-25-2012, 03:02 PM

i was considering the ampeg micro VR for this exact reason. and some of the Acoustic stuff. something about class D for me... i have 2 class D heads and 3 non class D heads and the non class D win. could be a coincidence, i dont know.. i read somewhere that class D hasnt really caught on for audiophiles yet either. probably an easy one for you to find would be an older swr electric blue head. the newer ones are class D however...(the combo is) doesnt traynor make some non class D SS heads?

IntrepidCellist · #4 02-25-2012, 03:25 PM

Eden WT550 or WT400. Small, well-voiced, powerful EQ, easy to find used. The 550 goes down to 2 ohms, too, so you can run two Thunderchild offerings off of one

JimiLL · #5 02-26-2012, 09:43 AM

Why is it so hard for people to believe two completely different designs, do, at tiumes, sound different from one another? Is there any scientific data to back this up?

Triad · #6 02-26-2012, 11:29 AM

I've played thru many amps and I must say that class D stuff, even on the high end (Epifani, for example) sound worse on the lows. They sound "hollow" if compared to old SS amps IMHO. The lows have a different texture, just like tube amps sound "better" than SS (for the same reason, superior "complexity" on the lows and a warmer tone).
I spent an afternoon playing thru several amps (G&Ks, Epifani, Ampegs, Markbass) and I ended up liking the G&K Backline300 over much more expensive class D amps.
My personal opinion is that, at least for now, class D amps don't sound as good as their older brothers. It's not a preamp issue, it's really due to the power section.
I'd go for something with a good toroidal transformer that doesn't weight more than 20lbs. There are plenty on the used market. Worth the extra weight IMHO.

(I had a LM2 and a G&K MB200... sold both of them and now own a pre-class D Markbass S450 and two tube amps).

R Baer · #7 02-26-2012, 11:52 AM

Quote:

Originally Posted by JimiLL

Why is it so hard for people to believe two completely different designs, do, at tiumes, sound different from one another? Is there any scientific data to back this up?

All depends on who you ask. Our engineer can go on for hours explaining the difference in power supplies and amp topologies and why they perform and sound different. True, watts are watts and most amplifiers will bench test alike with a sine wave tone and a non-inductive load, but he feels there's a huge difference in how that power is stored and delivered to the power section under a speaker load between a SMPS and a large toroidal transformer. As he explains it, loudspeakers present complex impedances and back-EMF that are always changing with the dynamics of the music being played. He also feels that every amp topology handles transients and power compression differently when pushed. Most of this gets way over my head, so I just trust my ears, but after hearing numerous power sections mated to the Valkyrie's preamp, I agree completely that it's not just as simple as saying "watts are watts".

I've also heard other engineers stating that all "well designed" power sections will sound exactly the same and they go on for hours explaining why. So, I guess in the end, it's up each player to make the decision themselves.

shwashwa · #8 02-26-2012, 12:05 PM

Quote:

Originally Posted by Triad

I've played thru many amps and I must say that class D stuff, even on the high end (Epifani, for example) sound worse on the lows. They sound "hollow" if compared to old SS amps IMHO. The lows have a different texture, just like tube amps sound "better" than SS (for the same reason, superior "complexity" on the lows and a warmer tone).
I spent an afternoon playing thru several amps (G&Ks, Epifani, Ampegs, Markbass) and I ended up liking the G&K Backline300 over much more expensive class D amps.
My personal opinion is that, at least for now, class D amps don't sound as good as their older brothers. It's not a preamp issue, it's really due to the power section.
I'd go for something with a good toroidal transformer that doesn't weight more than 20lbs. There are plenty on the used market. Worth the extra weight IMHO.

(I had a LM2 and a G&K MB200... sold both of them and now own a pre-class D Markbass S450 and two tube amps).

i kind of have to agree with the hollow comment. i especially notice it on my uprights, moreso than my electrics. i always use the same preamp, no matter what amp im playing through, and it just doesnt cut it for me when im using my class D amps. this is not a scientific controlled study, so it may just be coincidence, but for now i dont mind using the class D for electric, where im not as picky about tone, and ill use my other stuff for upright. (that goes for my AI head too. im not a huge fan of it for upright)

pudgychef · #9 02-26-2012, 12:49 PM

Quote:

Originally Posted by Triad

I've played thru many amps and I must say that class D stuff, even on the high end (Epifani, for example) sound worse on the lows. They sound "hollow" if compared to old SS amps IMHO. The lows have a different texture, just like tube amps sound "better" than SS (for the same reason, superior "complexity" on the lows and a warmer tone).
I spent an afternoon playing thru several amps (G&Ks, Epifani, Ampegs, Markbass) and I ended up liking the G&K Backline300 over much more expensive class D amps.
My personal opinion is that, at least for now, class D amps don't sound as good as their older brothers. It's not a preamp issue, it's really due to the power section.
I'd go for something with a good toroidal transformer that doesn't weight more than 20lbs. There are plenty on the used market. Worth the extra weight IMHO.

(I had a LM2 and a G&K MB200... sold both of them and now own a pre-class D Markbass S450 and two tube amps).

but an LM2 isn't class D iirc

Triad · #10 02-26-2012, 12:52 PM

It is!

I'm referring to the LittleMark II, by the way.

IntrepidCellist · #11 02-26-2012, 12:59 PM

The LittleMarkII is not Class D. It's Class A/B.

Another great non-class D amp is the GK 800RB.

seamonkey · #12 02-26-2012, 01:04 PM

Quote:

Originally Posted by R Baer

All depends on who you ask. Our engineer can go on for hours explaining the difference in power supplies and amp topologies and why they perform and sound different. True, watts are watts and most amplifiers will bench test alike with a sine wave tone and a non-inductive load, but he feels there's a huge difference in how that power is stored and delivered to the power section under a speaker load between a SMPS and a large toroidal transformer. As he explains it, loudspeakers present complex impedances and back-EMF that are always changing with the dynamics of the music being played. He also feels that every amp topology handles transients and power compression differently when pushed. Most of this gets way over my head, so I just trust my ears, but after hearing numerous power sections mated to the Valkyrie's preamp, I agree completely that it's not just as simple as saying "watts are watts".

I've also heard other engineers stating that all "well designed" power sections will sound exactly the same and they go on for hours explaining why. So, I guess in the end, it's up each player to make the decision themselves.

If I recall right, it's been a few years since you decided on class-ab with your ears.

You might want to give class-D, SMPS another try. Many other manufacturers are going this route and they have ears too.

Triad · #13 02-26-2012, 01:07 PM

Uhm... now that I think about it maybe I'm wrong. Too much time passed (owned it a couple of years ago). Sorry for the mistake

Seamonkey: you'd be right if I didn't try all those amps only a few months ago (head to head, so no mistake that time)

Sounds like the toroidal beats them all but the tubes. Also compared directly my S450 with an LM250 one week ago. Even at the same volume the difference in tone was pretty big (same thing, a sort of "hole" in the lows). Don't think it was due to the preamp.

shwashwa · #14 02-26-2012, 01:14 PM

Quote:

Originally Posted by seamonkey

If I recall right, it's been a few years since you decided on class-ab with your ears.

You might want to give class-D, SMPS another try. Many other manufacturers are going this route and they have ears too.

id stay the course if i were him. new production non class D amp will be a niche market and he may be one of the only ones to fill it. ive been looking at the ampeg micro vr and the svt 3 pro for the non class D power section, and the fact that ive heard them both and like them alot. i have an old walter woods (pre class D) and a new one, class D, and i like the old one much better, problem is, the preamp is so tube like that sometimes i feel like i need more clean headroom before it starts to break up.

Triad · #15 02-26-2012, 01:20 PM

I guess the thing is: if you can carry a 20lbs amp then go for the toroidal transformer equipped stuff. Otherwise, if weight is an issue, there's no choice.

A/B or D class, the problem is the same (at least for my ears).
The MB200 was smallest and lightest but I prefer to carry 8-10kg more and sound "better". Without talking about the 30kg tube amps, that's a different world

seamonkey · #16 02-26-2012, 01:24 PM

True blind listening tests require setup, like gain matching, and making sure the signal is equally colored by the pre-amp. Old hi-fi salesman trick, have one volume louder, or contour the signal to the more expensive gear.

It may be best to separate the "Amp" part of the head testing by gain matching just one pre-amp to the Amp-in of the power amp section.

Triad · #17 02-26-2012, 01:28 PM

At least the volume has to be the same, that's for sure

I think the SA450 and the S450 have more or less the same preamp and the difference was pretty big (they're even rated at the same power). Don't know, if I ever find a small amp that doesn't have that strange "hole" in the lows I'm gonna buy it, period. Please notice that I'm not saying A/B and D class amps sound "bad" but if you drive the preamp signal to an old power amp you're going to hear the difference pretty easily IMHO.

mothra2 · #18 02-26-2012, 01:54 PM

Quote:

Originally Posted by R Baer

All depends on who you ask. Our engineer can go on for hours explaining the difference in power supplies and amp topologies and why they perform and sound different. True, watts are watts and most amplifiers will bench test alike with a sine wave tone and a non-inductive load, but he feels there's a huge difference in how that power is stored and delivered to the power section under a speaker load between a SMPS and a large toroidal transformer. As he explains it, loudspeakers present complex impedances and back-EMF that are always changing with the dynamics of the music being played. He also feels that every amp topology handles transients and power compression differently when pushed. Most of this gets way over my head, so I just trust my ears, but after hearing numerous power sections mated to the Valkyrie's preamp, I agree completely that it's not just as simple as saying "watts are watts".

I've also heard other engineers stating that all "well designed" power sections will sound exactly the same and they go on for hours explaining why. So, I guess in the end, it's up each player to make the decision themselves.

+1

wcriley · #19 02-26-2012, 01:54 PM

If "that strange "hole" in the lows" is caused by the class of the amp, why are sound companies using class D amps to power their subs?

Triad · #20 02-26-2012, 02:01 PM

As I said, they don't sound "bad" (I owned a few) but they sound worse than their heavier brothers. Never played thru a preamp+high end class D stack, though.
The problem could be they skimp on the power section of the bass heads? Maybe, or maybe not.
It's just my opinion, of course.