List of PWM Amplifiers.

[SiriuslyCold]

Ostenisbly, amplifiers with a switching output stage - encompasses digital and anlog input stages, regardless of linear comparator for pulse variation (thanks, John for the description)

Commonly known as digital amplifiers.

in a companion to the Digital HT receivers list, I think it may be a good time to start this thread. For those who are looking for more power and a higher end implementation of the (relatively) new technologies


Acoustic Reality http://www.acoustic-reality.com/
eAR202, etc (ICEPower)

Aivin http://www.aivin.com.cn/
DT300 (Tripath)

Analog Research Technology http://www.analogresearch-technology.com/

AudioArt (NL) http://www.audioart.nl/
Van Medevoort MA240 (Hypex UcD)

Audiodigit http://www.audiodigit.com/
MC 8x100 (Tripath)

AudioResearch http://www.audioresearch.com/
150.2, 300.2, 150M (Tripath)

AV123
X-Empower, xAmp (prelaunch)
(Philips class-D?)

Axiom Audio http://www.axiomaudio.com/ NEW
A1400-8 (ICEPower)

B&O http://www.icepower.bang-olufsen.com/sw1067.asp
(ICEPower)

BelCanto http://www.belcantodesign.com/products.html
Evo (Tripath) eOne (ICEPower)

Bertram http://www.audiokabel.dk/eng-main.htm
(ICEPower)

Bryston http://www.bryston.ca/
D250Z multichannel power amp

Carver http://www.carverusa.com/
300.2, 700.2, 1200.2

Cary Audio http://www.caryaudio.com/
A 306 power amplifier

Channel Islands Audio http://www.ciaudio.com/
D100, D200 (Hypex UcD)

Chapter Audio http://www.chapteraudio.co.uk/
Couplet Power Amp (proprietary WMP class-D)

D-Sonic http://www.d-sonic.net/
Magnum (ICEPower)

DIYCable http://www.diycable.com/
Exodus (Hypex UcD)

Egosys http://www.egosys.co.jp/
Audiotrak DrAMP (Tripath)

Elan http://www.elanhomesystems.com/
D1200, D1600 (12 and 16 channel power amps, Tripath)

Electronic Visionary Systems http://www.tweakaudio.com/
EVS-2 (ICEPower)

Flying Mole http://www.flyingmoleelectronics.com/
(proprietary class-D)

Genesis http://www.genesisloudspeakers.com
Genesis Reference GR180 (Hypex)

Gilmore Audio http://www.glacieraudio.com/
Raven, Raptor, Dragonfly m/ch (looks like ICE)

H2O Audio http://www.iceh2oaudio.com/
M250, M500 (ICEpower)

Halcro http://www.halcro.com/logic/home.asp
Lyrus

Huygens Audio http://www.huygensaudio.com/
MCD-1202, MCD-1802 (MHz Class-D)

Integra /Onkyo http://www.integrahometheater.com/
DTA 9.4 7x120W 8Ω

Jeff Rowland http://www.jeffrowland.com/
Model 501 (ICEPower)

Jjaz Audio http://www.jjaz.dk/
(ICEPower)

Kharma http://www.kharma.com/
MP150

LC Audio http://www.lcaudio.com/
Predator SE (ZapPulse)

Marantz http://www.marantz.jp
Opsodis ES-150 (D2Audio) 2ch virtual surround

Medius [DK] http://www.medius.cc/
A II, A III

Meridian http://www.meridian-audio.com
G95 DVD receiver system (Hypex UcD)

MG Audiolabs http://www.mglaudiolabs.com/
Symphony (Hypex UcD)

Midgard Audio http://www.midgardaudio.no/www/
(ICEPower)

MindCraft (NL) http://www.mindcraft.nl/
Media Amp One (Hypex UcD)

Murano-Audio (TW) http://www.murano-audio.com/
P500, P1000 (ICEPower)

NHT http://nhthifi.com/
Power2, Power5 (ICEpower)

Nuforce http://www.nuforce.com/
Ref 8, Ref 8b, Ref 9 (nPhysics proprietary class-D)

NuVo Technologies http://www.nuvotechnologies.com/
NV-P2100

Onkyo http://www.onkyo.com/
A-1VL, A-9755, A-9555 (Proprietary)

Primare http://www.primare.net/
CDI10 (Proprietary Ultra Fast Power Device (UFPD))

PSAudio http://www.psaudio.com/
GCA, GCMC, Trio A100 (ICEPower)

Red Dragon Audio http://www.reddragonaudio.com/
(ICEpower)

RedWineAudio http://www.redwineaudio.com/
Clari-T, Lotus (Tripath)

Rotel http://www.rotel.com/
1077 (7x100), 1092 (2x500) (ICEPower)

Seymour AV http://www.seymourav.com/amps.asp
Ice Block Amps (Ice Power)

Sharp http://www.sharpusa.com/
SM-SX1, SM-SX100

Sonneteer http://freespace.virgin.net/sonneteer.audio/bronte.html
Brontë (Tripath)

Sony http://www.sony.com/
TA-DA9000ES, TA-FA1200ES (S-Master)

Spectron http://www.spectronav.com/
Musician, Troubador (int amp w digital inputs)

TactAudio/Lyngford http://www.tactaudio.dk/ http://www.lyngford.com/
Millennium & others (Equibit)

TEAC Esoteric http://teac.co.jp/av/esoteric/
AZ-1 pre-main (translated), AI-10 (Texas Instruments)

ThetaDigital http://www.thetadigital.com/
Virtu PowerDAC (Zetex class-Z)

UniwaveTek http://www.uniwavetek.com/
Anaco II

Wyred4Sound http://www.wyred4sound.com/
STI-500, STI-1000 (ICEpower)

Yamaha http://www.yamaha.com/
MX-D1


I'm sure you all have more information and companies.

[GoldenEarDrums]

Hey SC,

It was my intension to do this at the "Paradigm Shift". I was just waiting for the "weather" to change there a bit before I do so but thanks for the post .


...

[GoldenEarDrums]

Looks good... except some do have an analog output stage but PWM in design and nature.


...

[SiriuslyCold]

Originally Posted by GoldenEarDrums

Hey SC,

It was my intension to do this at the "Paradigm Shift". I was just waiting for the "weather" to change there a bit before I do so but thanks for the post .


...

sorry I pre-empted you! heh heh

I hope won't be able to maintain a alphabetically sorted list for much longer though (cuz I'd have to include all the audio companies and new ones to boot)

[GoldenEarDrums]

That's cool, no biggy.




...

[SiriuslyCold]

feel free to add stuff, and i will try update the first post

[GoldenEarDrums]

B&O...






...

[SiriuslyCold]

http://www.stereotimes.com/MWC0511043.shtm

check out how many of the Hall of Fame winners for 2004 are erm, digital.

[GoldenEarDrums]

Dang! SC, great find... now I won't be able to sleep.

Did you see them speaker cables?....


...

[SiriuslyCold]

GED speaker cables on where? wasn't looking... but I will now

I think Theta Digital are er, digital

http://www.thetadigital.com/product/.../prod-info.htm

using this Zetex ZXCW8100 chip (download specs, PDF)

[GoldenEarDrums]

Page 2...

SILVERSMITH PALLADIUM INTERCONNECTS and SPEAKER WIRE -- 6FT - $10 grand

Look at the smile on that guy's face.



...

[SiriuslyCold]

if i could sell a couple of lengths every so often, I'd be smiling too! LOL

[John Kotches]

There are a few bones to pick here.

The use of "Digital" is a misnomer. Class D, or "switching output stage" is a much more accurate description of this type of amplifier. Until you have a digital signal directly feeding the amplifier stage, it isn't a digital amplifier. There are a few that can rightly be called a digital amplifier, including the Tact, Sharp and the Spectron with digital input but that's about it.

Theta Digital's Dreadnaught II with 275w of idle power consumption for 5 channels (55w/channel) cannot be a switching output stage power amplifier. They did announce an amplifier at CEDIA with a switching output stage, but I don't know the model. It isn't the Dreadnaught II, which is a traditional class A/B amplifier.

I do not like the use of the term digital applied loosely. It's not that I don't like switching output stage amplifiers (I do), but rather that I prefer being accurate in our use of terminology

Best,

[SiriuslyCold]

John,

point taken, thanks. I'll take any suggestion as to what to lump these under

(non~analog?)

[GoldenEarDrums]

Interesting and good point John.

While "Digital" is a misnomer for most, "Class-D" or "Switching output stage" in general are not accurate terminology for them as well in general. One thing that they all do have in common is the use of PWM in their circuit. The use of PWM is something you won't find in the "analog" classes of amplifier.

PWM and Class-D amps also goes hand-in-hand by description (see Wikipedia). Often they are refered to as one. In reality, it is true that Class-D is a PWM amp but not necessarily true the other way around.

Maybe "Analog" too is a misnomer as "some" of these amp brand theirs as such. It seems that this is due to the fact that in the current amp world such terms or branding as Digital, Class-D, PWM is somewhat of a turn-off. Wether it is misinformation or lack thereof, maybe it is bad publicity or lack of exposure we just don't know. Confusion has run-amock in the CE world.

What shall we call these "Digi-Amps" (as I have labeled them)? I think that question is best answered by the proper authorities. For the meantime, I will refer to them as Digital or Digi-Amps.


PS: Your welcome to coin a cool name for it that I may be inclined to use.


...

[Yves Smolders]

OK, I've seen this in a lot of threads now... maybe time for new terminology. My proposal:

If the output stage is not used in a linear way but the transistors "pulse" into an output coil, call them "Pulsing" amps.

If the input is analog it's an analog pulsing amplifier.

If the input is digital it's a digital pulsing amplifier.

If there is a digital conversion (PCM>PWM or DSD>PWM) call it a direct digital pulsing amplifier.

Hmm... I should take a patent on this

But seriously, it's an easy to remember pretty much sums up how the thing works? I'm changing my signature to match this proposal, lol - there's till things not explained in these words of course... but your can't put everything in there. For example, fixed frequency or self-oscillating comparator designs.

[SiriuslyCold]

Yves

good suggestion - though pulse doesn't exactly describe the on-off state. or does it?

no one for my suggestion in the other thread "Binary State"? heheh

Check out my new BS amp!!

[GoldenEarDrums]

"Check out my new BS amp!! "

I never made that connection SC.

Good suggestions Yves. Although "PWM amplifier" is the closest current term to use for them in general. Although it doesn't have that pizzaz (at least to me).

In regards to UcD, that's the magic of USB, it is easy to convert it to any format (input/output) you want. It also (can) carry analog audio and video signal as well. So it is easy to implement to just about any application. Same goes for Firewire (iLink/IE3-1394).


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[John Kotches]

Siriusly:

Actually switching output stage is an apt way to describe a pulse width modulation scheme. They are one and the same.

The question becomes this, is the PWM scheme handled by digital means or analog means, and is it fed an analog input or a digital input.

These, as well as what is used for the linear comparator (for pulse variation) are what distinguishes the various designs apart.

Cheers,

[Yves Smolders]

I'm just looking for a good name that Joe Average can use...

People have no need for an lateral-piston induced wheel engaging motion entity? They want a car.

[SiriuslyCold]

John (and everyone else)

can we go with PWM then? it seems to describe how the speakers are fed power and encompasses any source signal

just so everyone knows what to expect when they click on this thread (in which case 'digital' would do) and until someone comes up with a better acronym than BS *LOL*

[GoldenEarDrums]

PWM it is (for now).

Politically
Wrong
Misnomer

PWM

Hah hah!


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[SiriuslyCold]

*LMAO* ok, changed the topic and 1st posting

[noah katz]

So when does anyone think we'll see reasonably priced standalone digital amps?

Right now it's like the early days of digital projectors, where it cost 5X for 1/5 the complexity and weight.

[GoldenEarDrums]

Consider the Panny XR55 as a stand alone with some extras.




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[SiriuslyCold]

Noah,

AV123 are working on something reasonably priced.

IMO the eAR 202, at $600 for 200Wx2 isn't astronomical

[blazar]

i'm not aware of a class d style amp made by theta yet....

it's also hard to classify something as an amplifier versus an integrated when an amp has a digital input and volume control.

The old classification systems get thrown out and "separates" must be redifined. eventually if they improve to the point that pcm->pwm surpasses standard d/a converters then there may no longer be a need for separates in their current form.


The yamaha mx-d1 has decent measurements on stereophile and the published stats in the manual. I wonder if anyone has forked over close to three thousand bucks for one of these units. They certainly aren't cheap despite being from yamaha.

[SiriuslyCold]

OK, I'll take ThetaDigital off the list for a bit until we can find solid references.

Originally Posted by blazar

The old classification systems get thrown out and "separates" must be redifined. eventually if they improve to the point that pcm->pwm surpasses standard d/a converters then there may no longer be a need for separates in their current form.

which is what PSaudio are saying with their GCC control amplifiers


Edit: Theta Digital - news on Stereophile

Theta Digital, for example, had a static display on the floor of the Dome, but that didn't stop me from investigating what the company was up to. Taking pride of place on their stand was a relatively small power amplifier that nevertheless packed seven 150W channels of highly efficient class-D (PWM) power into its chassis. The Virtu PowerDAC features an all-digital signal path—it has digital inputs only, on four S/PDIF RCA jacks, for L/R Front, Center, L/R Surrounds, and L/R Rears (Sub is ignored)—and uses new technology from English company Zetex for converting PCM digital audio to the PWM format used to switch the amplifier's output devices.

unfortunately there are no references on their own site.

[noah katz]

"AV123 are working on something reasonably priced."

Interesting, thanks.

[dsmith901]

If you are including receivers you can add the Sherwood Newcastle R-903 TruDigital™ 6.1.