Seeking listening help in Austin area


I live in Austin and have built an amplifier that I designed for magneto-static loudspeakers, specifically Magnepans.

I am looking for listeners to critique the sound of the amp. It is physically it is built on a wood board and is meant for 'first-ear' listening evaluation and learning only, it will not survive shipping so I have to hand deliver it and pick it up, thus Austin and the immediate area.

If you have a basic Maggie system the you know well I would like to bring the amp over and have you change it out with your amp, you listen, and tell me what you think it did to the system. This is how I learn to improve a design.

The is a Concept Amplifier, to my knowledge there is nothing like it. Class-A, no feedback, current mode gain, very high bandwidth and most uniquely, the distortion does not change with frequency and that is uses over 700 transistors to accomplish 50 watts per channel.  Results so far have been exceptional and I want to learn more. 

If you would be interested in listening and telling me what you hear, I would be glad to bring it over to audition.

Thank you,

Barry Thornton 512-266-7142

barryaudiophile

Showing 3 responses by audiokinesis

@geoffkait , It looks like I misunderstood what you meant by "twice the volume".  

It can mean "subjectively twice as loud", which is generally considered to be +10 dB.   That's now I'd normally use the term.

But it can also mean "equivalent to doubling the amplifier power", which would be +3 dB, which is indeed what we'd get from sitting half as far away from a line source.

Duke

"What in the Hell is "electroscopic" and "mangetostatic" operation?!"

Insight that Barry is more of an amp guy than a speaker guy.

"Class-A, no feedback, current mode gain, very high bandwidth and most uniquely, the distortion does not change with frequency"

It sounds to me like Barry is solving problems that really matter to the ears, even if they don’t necessarily result in the most impressive traditional specs.

Duke

I’m a speaker guy, not an amp guy



Hi Spencer,

I'm afraid that you do not get as much SPL increase from moving closer to the SoundLabs as you do with conventional speakers.  Likewise you do not get as much SPL decrease as you move further away.

The reason is, the big SoundLabs do a good job of approximating a line source, while most conventional speakers approximate a point source.  SPL falls off by only 3 dB for each doubling of distance from a line source, as compared with 6 dB for each doubling of distance from a point source.  Likewise SPL increases by only 3 dB for each halving of distance from a line source, versus 6 dB for each halving of distance from a point source.  These numbers don't take the contribution of room reflections into account, but these trends hold up well in a home listening room.  

In fact, at very close range, the SoundLabs approximate a planar source, with virtually ZERO change in SPL as distance changes!  The difference in SPL in going from 1 foot down to 1 inch is negligible. 

Duke