Need info on amp rec. for these Thiel cs2.4's


Ok, this is my last attempt before I have Crutchfield take the speakers back.

let me say that when things on these speakers sound right it trully is amazing. On most other average CD recordings though the speakers sound tends towards the brighter side. I just recently purchased a NAD M51 DAC and it helped and is a first rate piece of equipent - I have a review on Audiogon if your interested. However, while Im generally happy with the speakers I think either I need to change the amp or get a CJ preamp - ET2 (or similar). Im using the NAD to drive the Amp (a Vincent sp331 - 150 @ 8 ohms and 300 at 4 ohms) directly so no preamp at this time. I hooked up my friends 5082 Adcom for kicks and the treble is good there, but there is no space or dimension to the music. Thus my thoughts on changing the amp. Its flat. He also has a VTL 2.5 preamp that helps by the virtue that it is a tube piece and helps plump up the mids while softening the highs (thus my thoughts of CJ preamp). However sticking a piece of equipment in between the source and amp seems like a backwards step.

Im dedicated to at most $3500 dollars to bring the system in line for the hights. Problem is I have nowhere near me that I can go to listen to the equipment before purchase so its all online for me, so I'd need to be able to puchase it that way. Im not a big fan of used but I could go there if necessary.

Some thoughts on amps:

Channel Islands d200 MKII
Parasound Halo 21

Preamp thoughts:

CJ ET-2
Rogue 99

What my thoughts on what the amp should do is be warm, solid state, not emphsize the highs obviously, balanced or unbalanced, and have at leat near if not more that 300w into 4 ohms. I've heard dampening is important with Thiels but not sure what the numbers mean.

Please any thoughts would be appreciated on my situation here.

My urgency in this is I have till May 17th before I need to tell Crutchfield to take them back.

Now I do really like the speakers and I know many people will tell me to do just that - they are so close to being "there"! But let's use that as a last resort on info here b/c I know I have that option.
last_lemming

Showing 4 responses by mapman

Bel Canto ref1000m monoblocks might come in used at around your budget and would have a good chance of ending your amp search for the Thiels.
ref1000m's are lean and mean, no doubt (damping factor of 1000 as I recall), yet also most muscular and articulate. There is no flab in the sound whatsoever FWIW. That was the first thing I noticed when I first hooked them up. That might be a good or bad thing depending on the speakers need for damping. Some might endup sounding too lean, depending on personal preference.

THe ref1000ms are the perfect mate to the OHM Walsh speakers, especially my larger 5s, which are my mains. I think they are are a very good match with my smaller monitors also (Dynaudio and Triangle) however I could see where some might prefer less damping (more like a tube amp) with smaller monitors or even floorstanders with smaller drivers that might not be able to let loose as needed with such high damping. A damping factor of even 50 on a SS amp is generally considered to be fairly high and sufficient in many cases.

My impression of the Thiels is that they are a difficult load to drive similar to the larger OHMs, and a natural candidate for a Class D amp accordingly, though my recollection from hearing Thiels in the past is that they may tend towards the leaner side of things soundwise to start. I still think a highly damped Class D amp could deliver some very unique and extraordinary results with Thiels, similar to what I observe with Dynaudio. The BCs smooth and fatigue free top end could be a match made in heaven. I would expect similar things from the Channel Islands, but have not heard those so cannot say for sure.
"My understanding is that class D amps use PWM (I think I have the acronym right) thus it would seem their sound is "interpreted" if you will just like CD's have to "interpret" between the bits. Is my thinking right on this or am I off base? "

I believe you are correct that Class D amps use PWM (Pulse WIdth Modulation).

I'd say it is accurate to say that the sound of any amp (Class D or otherwise) is "interpreted". The mechanisms used by different types of amps vary however.

"I'm I losing audio information in a digital amp?"

Since no amplifier is perfect, I would say yes, however, again same true of ANY amp design.

Class D amp technology is relatively new and innovative. From what I hear I would say Class D amps are competitive soundwise with other good amps out there these days, perhaps even with some at much higher price points. Like most things, there is no definitive "best". It all depends..... In the end, you just gotta do your homework and trust your own ears.
"So, if the class-D amp is designed correctly, information-wise you should not be losing any information."

Bombay, my point was that technically no amplifier in practice (as opposed to theory) is perfect, so there is always some information "loss" or perhaps transformation (not completely reversible) would be a better term.

I would agree though that whatever you choose to call this, its no more of a concern with a well designed Class D amplifier than it is with any other amplifier type, so practically no reason for concern (at least in theory).

In the end you gotta trust your ears. Theory and its practical realization in design and construction are two different things.