Axiom Home Page Forums General Discussion Advice from Axiom Owners What is the lowest power amp with m80's

Has anyone ever experimented with a lo power SET amp? I have a fantasy about pairing up my 2 watt per channel SET with some 80's. I'm pretty sure it will be a no go, but the effiency looks like it is there.

Lampy, maybe the lowest power amp use that's been reported here with M80s is when Mojo connected the amplifier in his wife's boombox(probably about 2-3 watts realistically)to his M80s. At a moderate listening level the result wasn't audibly different from a high powered receiver.

Considering that the sound level at a typical listening distance of about 10'(both direct sound and room reflections taken into account)would be about 86dB for 1 watt with the M80s, a 2 watt amplifier would be okay for a peak level less than about 90dB.

Mojo would be proud

Thank you JohnK.
I think I am going to find someone in my area with m80's and hopefully they will let me bring my amps over for a test drive.

I may have to try this experiment just to see it for myself. I don't believe it.

Not even with really expensive speaker cable...

This little amp I just ordered, despite it's marketing claim, probably puts out only 5-6 WPC cleanly. I'm looking forward to trying it with a few different setups (including my M60s) to see what it can do just for the hell of it!

If it works OK, maybe I'll buy a bunch of them for a setup in every room

Well, clean is certainly the issue. I don't doubt you can get 86db of sound or whatever the math says, but I don't see getting the same sound quality at 86db.

Ummm, you bought that for your Mom...............Right?

Yeah, but I get to play with it for a couple of weeks until I visit her next and install it!

Context is everything.

Ugh! That was beautiful. Ya gotta admit it was a softball...but outta the park it goes!!

Hopefully the playing... Not so much the installing.

Charles, for a bit more detail, here's the page where Mojo described his blind-test experiment.

That is interesting. I'd like to see it matched at 95db as I think that is nearer the "real" sound volume and presents peaks well in excess of what some amps will control.

But, I do concede that even at 75db I'm very surprised (and skeptical) about the test results. Again, just comparing my Denon to my separate amp, there is a quality of sound difference. Not "warm, or bright or blue or green", just a very obvious harshness on certain male vocals and horns and some guitar notes that does not occur via the separate amp.

Anyway...

Lampshade,

If you are going to connect your low-powered SET to someone else's M80s, be very careful not to turn it up so that it clips. Clipping is clipping, whether from a tube or solid-state amplifier and that can certainly endanger the tweeters.

You'd likely hear a kind of mushy distortion and collapse of the stereo soundstage before the clipping would damage drivers.

Regards,

Alan

Just remember he was comparing to his Denon 2805, not much of a leap when you think about it this way, but comparing it to an outboard amp, huge difference IMO.

Alan,
that is very interesting. I am glad you told me that. I thought that tubes clipped "softly" and would not damage tweeters. I know of the collapse you mentioned because I do drive a pair of 89db speakers with the SET.

I know it won't drive the 80's to be really loud and I am just curious to hear how it good it sounds.

Thank you for everyone for the stereo input and the mother jokes.

Lamp,

In terms of listening, tubes do clip "softly" whereas the solid-state amps generate a nasty hard distortion. However, if you view the output of an amplifier on an oscilloscope, monitoring the waveform as the amplifier reaches its output limits, a tube amplifier is just as capable of flattening the waveform as a transistor amp. It's just a more gradual escalation towards distorting the waveform.

As the waveform becomes more "clipped", it begins to approach DC, which is what will damage voice coils of any driver.

Alan

I used a 5 wpc SET tube amp to drive a pair of M3s. It was one of the best sounding systems I've ever listened to. M80s are as efficient as M3s though a more difficult load to drive.

I have a Kenwood KA 9100 2 channel integrated amp driving a pair of M22s (previously Dahlquist DQM 905s) in my garage system. The meters indicate that at decent listening levels the amp was rarely asked to put out more than 2-3 watts.

Of course, tube amps are known for soft clipping so low power tube amps are unlkely to hurt your M80s.