Re: Which amplifier NOT for SHL5
Before I hand this over to others for comment, I'd like to clarify a couple of important points from my side, as the designer of the SHL5.
Originally Posted by heflo
First, as I have stated here before, ANY competent amplifier regardless of age, solid state or tube, inexpensive or expensive, integrated or separates providing that it is in original condition and serviced to specification, will work very well with the SHL5 - or indeed any other Harbeth. I do not think that very small amps offering just a few Watts are really ideal for such a big speaker but even I have been astonished by how well a 300B (tube) amp can drive a SHL5 under non-controlled listening tests.
Second: It worries me that implied in the question is that there is some characteristic of the SHL5 that demands an amplifier of specific (high) performance. This is completely untrue.
Third: As I have also said before here, during the design process (of any Harbeth speaker) I keep a very close watch on my simulator's prediction of the loudspeaker systems impedance - the load the amplifier sees - to be absolutely sure that the speaker will work with any competent amp. In fact, I have two Windows open on my (widescreen) monitor and in one I have the frequency response and in the other the impedance curve. As I make changes to the crossover which changes the frequency response I watch the impedance and no matter how attractive the new system frequency response is, if the system impedance drops low and/or becomes reactive, I immediately abandon that line of design attack and seek another with a more benign impedance.
Yes, it greatly extends the design process; it is frustating to have an extra level of concern (aside from the frequency response) but it allows me to be nearly 100% sure that I am not swamped with after-sales calls concerning amplifiers - and the proof is that nobody asks me: it is a non-issue.
Fourth: Again, as stated before, I use very modest electronics right through the design process. Nothing fancy, and available for little money. If I can get great results from such humble equipment - imagine what you can achieve if you want to invest serious money! But it is not necessary to junk perfectly good electronics to become a member of the Harbeth club. Nor, from an ecological point of view should you.
If you can point me towards an amplifier that meets my criteria above (i.e. is in proper serviceable condition, to original spec) that gives you problems I'd be very keen to borrow it!
Sorry if this sounds a little hard - but we really do not want to create the impression that there is a problem when there most definitely isn't.
Alan A. Shaw
Harbeth Audio UK