Question re input Sensitivity and 110 db speakers

In addition to the speaker sensitivity problem, you may also find that it will amplify any noise in your system, especially that in your power amp. I would try it first to see how it works.

Thanks all; there are no specific speakers that I had in mind, it was a theoretical question, since I have had so many divergent answers from friends about the versatility of a 60 WPC Class A amp with 125 mV input sensitivity that I wanted a consensus, concerning the range of speakers that I could use - I have previously had a thread concerning the other end of the spectrum - 85 db 4 ohm speakers, that I chose the highest sensitivity of speakers that I am aware of, to determine users's experience at both ends of the spectrum.
This all stems from my Denon APL 3910 putting out 4 volts and clipping, as well as a ML 32 preamp clipping Atmas-Spheres when the db gain was higher than 12 - took me weeks to figure out that the input was too high. Long answer, but that is what this is about: trying to tie together inputs, outputs, amp and speaker sensitivities, having been burned twice (but fixed both times). I'll get the answer by taking the amp to an audio dealer with a variety of speakers. But I appreciate all the help. Thanks again.

So what are the 110 db sensitive speakers?

I doubt you will need an attenuator or padding of any kind, though it certainly is an option. I've used powerful amps with 104db LaScalas and had no such problems as you're anticipating. My friend was running a 200wpc Mac amp with Khorns which have a 104db efficiency rating - Don't recall any problems there. I'm currently running 500wpc mono amps into 92db efficiency speakers with no problems at all. I don't get much past 9 O'clock on my volume, but that is really not a problem (it still is a smooth transition, over a shorter rotation). The combination I'm using sounds wonderful to me (not necessarily because of the pairing of high power and efficiency). Obviously your speakers are likely a great candidate for lower power SET amps, as Tarsando points out. That's not to say they can't sound great with another option. Certainly with the higher power amp you will not have to use nearly as much of the volume, but it is not going to be an all or nothing scenario.

Marco

I said it won't necessarily work. I bought some rothwell attenuators for a preamp whose output was so great that I could not use it. Adding the attenuator made virtually no difference--not enough to make the preamps volume control usable. THe key is your "well chosen"...value for the resistor. Give the original poster the right value and sure....but I don't know what value to tell him. Do you?

I am curious to know which speakers are you using that have that sensitivity. I know Klipschorns were rated at about 102db, but 110db completely blows me away.

Tarsando, why won't an attenuator help? Please explain.

As far as an attenuator taking away from the precious signal, some designs place nothing more than a resistor in the signal path. We're all in trouble if a single well chosen resistor can make that much of a difference.

for me this was always a problem and these in-line att's are taking too much away from the "precious" signal...Generally I would only use maximum 10W amplifier with the 110dB speakers to have it " matched"....

Well, if you don't actually HAVE the amp to test, I think the conceptual answer to your question is--no the amp is too powerful. Even adding an attenuator (a fixed one anyhow) isn't necessarily going to help. I would have thought the whole point of using such wildly efficient speakers would be to use a very low powered set tube amp.

Try it and see if it works to your liking. From the specs you've provided you can't really judge the usefullness of the volume control. If it does turn out to be too sensitive it can be easily remedied via an in-line attenuator (Rothwell, Endler, etc.).