Anything new better then UCD sound?

[Kip]

I have a pair of mono amps based on UCD700 modules. I have been using these for about a year now. Has class D technology in the last year advanced over what I have? Truepath looks interested, but there isn't any comparisons. I would like to buy or build something newer and better. I don't need 350wpc, but would like at least 200wpc into 8 ohms. NewclassD looks interesting as well. Any comments from the group on what you would do? I don't want to take a step backwards in sound quality.

[john65b]

Try building a Class A amp - An Aleph 60 or Krell KSA50 Clone. Not Class D, but it just may surprise you, as it did me.

I have a UCD400 that gets no play time now that I built the Krell Clone (search for building wiki). A little more work than the typical UCD.

400 wpc UCD vs 70 wpc Krell Clone on a pair of Magnepan MGIIIa. You would never notice the wattage difference.

Just my 2 cents.

Also like my ESP P-101. 380 wpc and really can grip the maggies. I don't know if I like it more than the UCDs tho, but its close.

Are you driving a difficult load? With 700 wpc monos, I would think your running Apogees, Magnepan, Martin Logan or something similar??

[ArthurG]

I recommend you the new Red Rocks Audio D200. Based on NXP integrated class D chip, this little baby sounds amazing with proper power supply. And the price is very cheap too...

[classdphile]

Originally posted by ArthurG
I recommend you the new Red Rocks Audio D200. Based on NXP integrated class D chip, this little baby sounds amazing with proper power supply. And the price is very cheap too...

What chip is that exactly, I wasn't aware they made an IC of UCD... which this is obviously borrowing from, while offering an amateurish layout.

Unlikely that this could be better than the real deal.

[fredex]

Are you chasing rainbows ?

[bwaslo]

NXP integrated Class D:
http://www.nxp.com/acrobat_download/.../TDA8950_1.pdf
Definitely not UCD (isn't self-oscillating, all feedback is before output filter).

I wonder why they did that?

[ArthurG]

Originally posted by classdphile



What chip is that exactly, I wasn't aware they made an IC of UCD... which this is obviously borrowing from, while offering an amateurish layout.

Unlikely that this could be better than the real deal.

UCD is not the real deal. UCD uses one topology and NXP IC another one. They are totally different products. And putting everything in one IC has many advantages, for example in terms of timing...

[DcibeL]

Hi Kip,
You could try the ExtremA, a Class-A amplifier designed by Bruno Putzeys. You can read about it here.

Realistically it is going to be difficult to better a pair of UcD modules, and I don't think you are going to be satisfied with just another high end class-D offering. Maybe you could try some different/better speakers before deciding that you don't want a pair of UcD700 monoblocks anymore.

[classdphile]

Arthur, you seem to not know what you're talking about. You made the claim that redrocks uses an NXP IC class d controller, where did you hear that and which one is it.

From their website:

"The imPULSE D-200/*1000 modulation system uses a self-oscillating high frequency circuit that does not require an external clock. Also, the used feedback includes the reconstruction output filter in the loop. This way, the amplifier can correct load anomalies or defects at real time without using additional filters or zobels at the output, making the frequency response constant at any time, not influenced by load type or impedance."

That screams borrowed UcD topology, as do the FFT themselves. If anything they're using NXP mosfets to take advantage of the free licensing offer, but that's a very different thing.

If it is as I supect it to be it makes no sense recommending it as an improvement over its obvious superior, original solution.

So before we go on to discussing the merits of IC class d controllers and what the real deal is that you seem expert on, answer the first question I asked you by stating where you got your information and exactly what chip they use that fits the above description from their website such that it can be verified.

[Kip]

My speakers are Gemme audio Tantos V. 1 and i have a pair of ProAc One SC clones I built. I was always interested in class a amps but read that the Krells were bright as well as the Pass Labs stuff. I am looking at Butler amps, but don't want to sell my UCD700 amps for something inferior. I was hoping there may be something new to built in class d that might better what I have. Mine are the ad version with three Plitron transformers. They sound great, I am just looking for a change. You guys know how it goes.