What is stopping the ultimate?

Sean, any good resources for single point source driver loudspeakers? If you have any please list, thanks. Melhuish.org is very good if you do not already use it.

I remain,

Tacs. There is a lot of truth in what you say.

Why such direct things are not done is a wonder to me. Seems you like to think about these things. Answer this for me. Amp makers always measure distortion as voltage amplitude distortion , almost exclusively. It's almost all they care about - using negative feedback ect... But a driver-transducer is current controlled. Most amp makers never worry about this. It's important because the current in the driver's coil is going to be the output voltage divided by the speaker's impedance right(ohm's law)? This means that as the speaker's impedence fluctuates all over the place (with frequency and voice coil temperature) the current does too. Current will only be linearly related to output voltage if the speaker presents a purely resistive load which it never does. Anyway, the impedence fluctuations translate directly into distortion of the current driving the coil. To me this is why you get so many amps that sound crappy with certain speakers. Do you get what I mean? I like to make speakers as a hobby and i have always wondered on this point. It seems the amp people are so focused on one thing they fail to see what is important to the speaker-current. I do not see it even discussed. I believe you would have to raise the amp's output impedence to deliver more consistent current. Tell me what I'm missing.. as I said I just like to mess with speakers and am not an EE or anything.

Sincerely, I remain

Ehart. I'm not talking just about the amp's ability to throw out current in my post but I agree with you totally. Power (in watts) is voltage times current and you need both. Current is needed when the load goes low. I agree with you as far as you go.

But I am talking about another issue in addition. Providing STEADY current into a varying load (the speaker) which gets very little attention as far as I can tell. Amp folks talk a lot about steady voltage output and the speaker coil is a current issue which should be kept constant as possible. This is true even with high end stuff. When you do hear about current it's always this artifical discussion about an amp running into a resistive load. I may just not understand something. That is why i'm throwing it out for discussion. Some of the smaller set amps drive really effecient speakers with inherent damping and avoid the current issue talked about in the post above .. at least to greater degree than the high powered amps.. Maybe one of the reasons they sound better?

Sincerely, I remain

Detlof - ESLs. You are so right, raise completely different needs in amps and wire too. The ESL acts more like a capacitor in the circuit, and with a transformer there too, raises all sorts of unique inductance/capacitance resonance issues. Special concerns about the inductance parameters of your wire as far as I understand -which isn't too far. Helps so much to understand what can be measured and what is understandable -but in the end the reference is one's ears. Detlof-have you ever heard differences in highs, some unwanted peaks, due to wire alone?

With regard to conventional speakers, I still want to play around with the idea of an amp that is variable impedence and designed specifically for one load/speaker, which is a point Tac brought up a few posts ago.

An audio system is really one circuit and it help to think of it that way instead of as discrete, separate, little enclosed boxes. We don't buy a car from five different vendors; body from one, frame from another, motor from third, all not knowing what the others design intentions are.

Back to topic on this thread we are so far from ultimate that it is depressing if you think about it. The amount and kinds of distortion just in speakers is crazy. Harmonic, intermodulation, crossmodulation, mechanical resonance.....the speaker is playing it's own tune really and it will be this way until the driver diaphram's density is equal to that of air and has absolutely uniform acceleration over the entire surface at all frequencies. Requires a speaker with trillions of microscopic transducers and nanotechnology or something- Lynn Olson has some interesting things to say about this stuff and most of my opinions just reflect a few folk like him.

Joke: what do you call the time between the point you step on the banana peel and when you fall on your arse?

- a bananosecond

Sincerely
I remain,

Daniel: "I would say the audio press elite are the biggest anchor to advancement." Amen Brother.

Hype and gloss and big buck wannabe materialism instead of audio. Especially, as you point out, in tubes. All of the basic circuit topologies are how old? There have been a few interesting improvements but some basic old stuff stands the test. Give me an old st70 (sells around here for $250) and a soldering iron.

Where can I meet ya for that beer?

Sincerely, I remain