SS Amp for natural vocals

Well Rafael, not exactly.

The Jeff Rowland Design Group Continuum 500 integrated amp is only $8800, with 1000 watts into 4 ohms. It handles the DALI's very nicely. (I literally just walked in the door from listening to the Continuum driving the DALI 400s and the Vienna Beethoven Baby Grands, for about the last 3-hours).

I should say that I'm having second thoughts about the DALIs. I was disturbed that the DALIs don't really handle low bass as well as the Vienna Acoustics, losing the harmonic richness in a Johnny one-bass-note kind of response below a certain frequency. Given the price and size I'd expect much better bass resolution.

The DALIs excell at highs. They're incredible with things like fingers on strings and air in voices. The mids are also very good, but I prefer the VAs, that's without regard to price. If you consider price, then the VAs are an overwhelming choice for me.

Dave

" ...I was disturbed that the DALIs don't really handle low bass as well as the Vienna Acoustics, losing the harmonic richness in a Johnny one-bass-note kind of response below a certain frequency. Given the price and size I'd expect much better bass resolution."

Are you sure that it is the speakers fault? Given their price and size and REPUTATION, I would suggest to investigate if they were properly controlled to begin with.

I read on Spectron web site that rms power is very misleading number because in "rms" sort of mode you really need 1-5 per cent of this power ONLY. However, when push come to you know what.... amplifier must handle it and it may be hundreds times greater them "rms"..
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Spectron claim that their amp is stable up to 0.1 Ohm and during the "stress" can deliver 3500 watts over 500 msec.

Next, and it may (or may not be important) that peak voltage even for medium efficiency speakers is more then 100 volts and all solid state and class D amplifiers that I know (except Spectron and Mackintosh) have rail voltage of about 65 volts - thus if signal is 100 volts then its clipped.

It could be that you have incredible speakers which are very sensitive to the signal they are asked to reproduced... and they are simply doing that whereas other speakers mask it

All The Best
Rafael

I do know that the DALIs are very amp sensitive. I've now heard them with four amps and they sounded very different with each one.

My friend, are you suggesting that the DALIs may drop below 1 ohm in the low frequencies? I'll ask Jeff Rowland of the stress limits of the Continuum. He suggests using it with speakers with a nominal impedance of 3 ohms or higher. I suspect that it'll handle loads down below 2 ohms easily, but I haven't seen any test data of that kind of stress.

Since I'm buying the Rowland, the DALIs will certainly not be on my shopping list.

Dave

Oh, Rafael, overnight I thought about your comment that RMS power ratings can be misleading and then you go on to quote some amp's ability to put out 3500 watts into .1 ohm for 500msec. Well, I'm thinking that instantaneous power is interesting to know, but at what purpose? .1 ohm is next to shorting. Do any actual speakers present such a load? What musical event is going to occur from 500 msec, right before your amp fries or shuts down?

I DO agree that RMS can't possibly tell the whole story; however, I think that it's a good starting point. Yes, you only use 1 to 5% of that power continually, but I hear a correlation between power and control of the woofers in large speaker systems. I think that RMS is a good place to start in understanding an amp's ability to handle large, inefficient speakers.

BTW, the Continuum's two built in Power Factor Correction modules each deliver 385V DC, so I don't think that's a limiting factor.

Dave

"Well, I'm thinking that instantaneous power is interesting to know, but at what purpose?"

Let me quote from Spectron Web Site again as its very educational, for me at least:
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Stereo Times reviews Spectron Musician III SE
"Power and Finesse" by Donald Shaulis

"I have never heard Moussorgsky: Night on Bald Mountain/Pictures at an Exhibition [Telarc B000003CSH] before. Oh, I have owned the CD for years but I never really “heard it” before. The Spectron presented the softer passages with such inner detail they became seductive but the real surprise came in the crescendos. The peaks reached were a revelation. It wasn’t that the Spectron could play loud, it was that I wanted the music louder. For the first time the crescendos were reproduced with full fury but no smearing or harsh edge that demanded the volume be reduced. Now, after many years, I finally “get” this fine recording..."
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I am not professional reviewer and I can't say it so eloquently.

Good Luck with your choices.
Rafael