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jastrup
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Class D power amp with tube preamp?

Hi,
I would like to hear if anybody has experience with using a Class D power amp with a tube preamp?

I'm attracted to the low power consumption and small size of Class D as well as the reportedly authoritative sound. However, I'm worried that I won't like the unforgiving sound that a lot of reviewers seem to experience with Class D, and I wondered whether a good tube preamp would be sufficent to soften the sound?
Thanks,
Jens

dcstep
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Re: Class D power amp with tube preamp?

Jens, actually that would be a very good match, matching the euphonic attacks of tube pre-amplificaton with the speaker controlling power of a good Class D amp.

Some people diss Class D out of hand. I suggest listeing for yourself and buy based on what you hear. Look at Rowland, PS Audio and some others for high quality D.

Dave

Jan Vigne
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Re: Class D power amp with tube preamp?


Quote:
I wondered whether a good tube preamp would be sufficent to soften the sound?

I always cringe when I hear of someone wanting to use tubes to gain or subtract from a particular sound, especially when they want to "soften" the sound or "rolloff" the hard edges, in other words, to have "tube sound". This is placing a BandAid on an amputation. IMO it's akin to building a Chicago style Bungalow in downtown Hong Kong.

Ideally, you should be looking for something that injects as little personality into the final product as your budget will allow. Intentionally using any device as a coloring agent is heading in the opposite direction and will only place you at a disadvantage if and when you decide to remove the offending component from the chain. Then you're stuck with a patching component that has addressed the faults of the component you can no longer tolerate. What do you do then?

I would suggest you first find a class D amplifier that doesn't offend. If that's not possible, then covering over its flaws by intentionally "softening" those faults will only leave the faults while making them "softer". They'll still be there and you'll still know they are still there. I guess if you can drive for months with the space saver spare on one wheel, you could manage this. I think I would find it difficult.

A very well done tube pre amp can benefit a well designed power amp of any flavor or operational topology. Using any tube device to simply throw a blanket over your mistake is just repeating the problem.

dcstep
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Re: Class D power amp with tube preamp?

Class D is the way to go. When well executed it's the best overall sound, IMHO. Just listen.

Dave

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Re: Class D power amp with tube preamp?


Quote:
Some people diss Class D out of hand.

And the rest of the dissers are usually tube lovers!


Quote:
I suggest listeing for yourself and buy based on what you hear. Look at Rowland, PS Audio and some others for high quality D.

Ditto. Love mine. Select your front end carefully and you may find nirvana...without tubes.

RG

Jeff Wong
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Re: Class D power amp with tube preamp?

Another consideration is to address all the RF and EMI the digital circuitry a Class D amp is giving off to ease the harshness or stridency. People may laugh at Shakti Stones, but, they are beneficial, especially in this application.

jastrup
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Re: Class D power amp with tube preamp?

Hi, Thanks for answering. Maybe I should be more specific.

In my this case, I consider the recordings the offending component. I have often read that Class D exposes the recordings as they are - good or bad. Well, I think the price for that can be too high. I have several recordings where sound is less than optimal, but where the music is fantastic. I want to be able play and enjoy those, and if Class D or any other component hinders that by exposing all the rough edges, then, for me personally, it is not progress, even though it may be a more neutral reproduction.

Hifi is all subjective ... And it's all about matching components. So I would still be very interested to hear if anybody has experienced tube preamps as a, shall we say, counterweight to Class D's very revealing character.

Regards,
Jens

Jan Vigne
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Re: Class D power amp with tube preamp?

I've combined class T with a tube pre amp. Technically, it can sound a bit ridiculous since one of the benefits of class T or D is the inherently low to nonexistent noise levels of those topologies.

I would have to disagree with, "Hifi is all subjective."

dcstep
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Re: Class D power amp with tube preamp?

Jens, any good tube pre-amp will also reveal the sins of your source material. There's no way around that with a hi resolution system. The best tubes only slightly soften the attacks and it's extremely subtle. Most of us deal with this by gravitating to better source material, not bringing down the resolution of our systems.

An extremely good equalizer is what you seem to desire. Those are very hard to find. Cello made and excellent one for a few years, but they're hard to find and expensive even as used gear.

Dave

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Re: Class D power amp with tube preamp?

You can't discuss amplification without considering the speaker it will drive. Do you have a particular speaker that you own or have in mind?
Have you heard that speaker with any particular Class D or SS amp to come to the conclusion that a tube pre would be beneficial to the how the system sounds?
I do not consider a Class D amp any more revealing (this also depends on the speaker) than any SS amp of the same class. The typical reason for using any particular pre (not just a tube pre) is the characteristics of the pre itself. So any pre will just not do with any amp, they need to be matched such as not to work against each other.
Can I suggest you decide on the power/speaker combination first and then look for a pre (it could well be a tube pre) that works best with that power amp and the rest of your system.

jastrup
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Re: Class D power amp with tube preamp?

RabPaul. Yes, the tupe preamp I already have - an Audio Note M2. My power amp is a custom built SS, which I think has a fairly smooth sound, but I really don't know, because I haven't heard any other power amp in my own system for more than 15 years.

Jan: About "Hifi is all subjective". Maybe that was a little rushed. Sorry.

Anyway, thanks for answering. I still feel encouraged to give Class D a try.

Regards,
Jens

cyclebrain
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Re: Class D power amp with tube preamp?

A major concern with most class D amplifiers is their interaction with the reactive load presented to them by the speaker. The final stage of a class D amplilier is a low pass filter to remove the high frequency switching component. The reactive load presented by the speaker to the low pass filter of the amplifier can have a major affect on its response.

Buddha
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Re: Class D power amp with tube preamp?

I have no problem with "Hi Fi is all subjective."

I've yet to meet an audiophile that doesn't base his final opinion upon how something sounds.

If you can, check out the Channel Islands products. I've heard their class D amps driving the some of Von Schweikert V-Line speakers and they were utterly fabulous. (If I recall correctly, one of the rooms I heard that combo in had been treated by Ethan Winer, too!)

I think I could be happy with a pair of the Channel Islands D-200 amps driving my system. Plus, Dusty, the owner of Channel Islands is a long time well regarded member of the Hi Fi community.

Channel Islands = http://www.ciaudio.com/

cyclebrain
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Re: Class D power amp with tube preamp?

The Channel Island amplifier is a unique class D amplifier that is not effected by load reactance.

rabpaul
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Re: Class D power amp with tube preamp?

Can I suggest you listen to the Bel Canto S300, they use Danish built ICE Power Modules from B&O I believe.

cyclebrain
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Re: Class D power amp with tube preamp?

The Channel Island amplifier uses the Hypex module designed by Bruno Putzey formally with Phillips digital.
Some interesting technical papers out there by him if one is interested.

Buddha
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Re: Class D power amp with tube preamp?


Quote:
The Channel Island amplifier uses the Hypex module designed by Bruno Putzey formally with Phillips digital.
Some interesting technical papers out there by him if one is interested.

Thanks, man.

I have been really taken with those amps, and did not know about the different design.

I appreciate your knowledge!

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