Audio Research DS 450 amp......thoughts


....that's what I'm looking for, thoughts on this class D amp from this tube giant. Some people like like it.....what do YOU think if you have heard it
garebear

Showing 8 responses by flex2

Djcxxx.
Keep your VT200.
That amplifier throw one of the greatest stereo soundstages in the business.
I tried some class D amps incl. ARC 150.2 and 300.2 (still own it), but I never got satisifed with the timing and timbre of the upper registers.
The technology simply can't compete with traditional amplifers.
My 300.2 is a great amplifier for driving the servobass of my Infinity Epsilons however.
For higher registers ?
No thanks...
Replacing one of the greatest as VT200 are?
No, not a chance IMHO.

PS. Using VT-150SE for the planar drivers of my Infinity Epsilons where the do a fantastic job.
Garebear
IMO...Do not use ANY class D amp fullrange.
The technology simply can't compete with similar priced traditional class A or AB amplifier.
I have experience with Tripath, Hypex and IcePower.
All have failed to impress in the long run.

Esoteric make excellent products.
SF make colored products to my ears.
Still haven't heard a SF loudspeaker that are truly transparent and neutral.
But that is also a matter of personal preference.
I simply hate colored loudspeakers.

Regards
Garebear...
Cut from Audio Researchs website:

"The output stage is a high-speed pulse-width modulated (analog) switching design that also builds on the proven formula in the DSi200, but with twice the number of 500W power-mosfet output devices in each channel. With a 400 kHz switching duty cycle, the output stage stays cool under the toughest loads."

So it's a true class D amplifier.

If a amplifier should have a chance to let the upper registers and treble through in a fairly unharmed way the -3dB point should be 200KHz or higher.

DS450 have it's -3dB at 45KHz while 300.2 have it's -3dB point at 30KHz.
A slight improvement, but not enough in my opinion.
When they reach swithing frequencies at 2-5 MHz and have -3dB point in the 200-500KHz range there might be a chance that a class D amplifier can compete with a good traditional amplifier.

Don't we all remember how the first CD-players with brickwall filters sounded like compared to vinyl ?
Bad...
Real bad.
I would say that the same can be said about class D amps compared to traditional amplifier technology.
It simply lacks air and precision in the soundstage which also are compromised and in your face.
Timbre is lousy and it's very hard to hear any acoustic instrument as it was recorded.

Audio research's efforts still are some of the best in the market, but the technology itself are too undeveloped at the moment (for fullrange use).
Ritmo

I will absolutely give it a listening when I get the chance, and try to keep an open mind.
Audio research are and will always be one of my favourite brands so I will always listen to their products when I get the chance to do so.
Few other brands have been able to recreate the musical event as natural and vivid as ARC's more successful designs.
Efner
I you read my input a little better you will find that I don't bash DS450 in particular.
I bash the principle of class D amplifiers in general.
Read again and learn some about why the technology can't compete with traditional amplifier technology.
I hear a lot of different amplifiers, and until now I haven't heard any class D amplifier that sound really good.
And please remember, that is MY experience.
Yours might be different.
Palewin
Since it is my experience I can make a statement like that.
I have heard most of the "high-end" class D amps around.
Spectron, Rowland, Nuforce, Bel Canto, Embla etc, etc and none of them have been able to create a solid soundstage that I expect from a truly "high-end" amplifier.
Sooner or later we will see switching frequencies that allow for output filters at 200 Khz or higher, but until that happends the class D technology will be inferior to traditional amplifier technology.
...and please remember, that is MY experience so far so please don't tell me what I can't say or not...

If you have a different opinion please express it.
Perhaps you can mention a class D amplifier that can compete with a Audio Research VT-200 regarding soundstage and honesty to the recorded music ?
Because that was the original question that started this small debate...
Palewin
A lot of reviewers get blended by the emperor's new cloths.
For example:
PS Audio HCA was one of the first class D amps that reached a class A rating at Stereophile.
http://www.stereophile.com/solidpoweramps/729/
The words was "tubelike" "revolutionary" the best of the best and had to be considered regardsless of price.
Today reality have catch up, and if you even can sell one of these amplifiers you will only get a few hundred dollars.
I used to own one, and soon discovered that it didn't sound very well, so it was removed from my home after 4 months.

I used to own a 150.2 too.
The reason for buying it was for driving a pair of Magnepan 3.5R in my TV system, and the only reason for selecting 150.2 was for the posibility to keep it on permanently without the power consumption and because I really like ARC as a company.
It was paired with ARC LS12 as a linestage (lovelly sound from this little linestage).
I soon replaced the 150.2 with a Restek Tensor and the improvment was enormous.
The soundstage quadrupled in size and suddenly all complex acoustic instruments was rendered with full size and sounded as the real music event.
So sorry if I recommend that you try a different power amp that isn't a class D amp.

Sorry for Tom Martins decision to select 300.2 unless he use it for bass only as I do with my 300.2
...and of course I have tried my 300.2 for full range operation.
Does it sound good and cast a high-end soundstage?
I'm sorry but it doesn't.
It's dynamic and sound powerful, but it can't let the music through in a unharmed way.

From my point of view switching technology is best kept for powersupply service and leave the amplifing circiutry to traditional amplifing technology.
Two companies that have come to the same conclusion are Linn and Halcro.
Both have got some nice reviews from the press too.

But I expect class D technology to keep getting better and better and eventually it can compete with traditional amplifiers.
I will keep listening to them.
This is what I have found until today...

Do you remember the seventies when tube amplification almost died out because of the new revolutionary transistor technology ?
Today we know better...

I don't think we will see a similar evolution with class D amplifiers, but be aware of the problems with the basic technology that class D amplifiers are built on.
The industry will eventually solve them, but from my point of view it will take some years from now.
Palewin

Regarding the "T" class that ARC state it depends on the fact that it is a variation of class D amlifier with a variable switching frequency, but make no mistake, it's still composed of a comparator that compare a triangular wave with the signal and produce a PWM signal to drive the switching output transistors.
Just to vary the triangular wave switching frequency according to the demand of power will not make it a none class D amplifier.

There are some other versions of switching amplifier technologies (E/F/G/H), and there have been some examples of class G and H in the market. Usually for our portable audio devices.
E and F is for high frequencies and not suitable for audio.

Please read more here if you want:
http://en.wikipedia.org/wiki/Electronic_amplifier