John Curl's Blowtorch preamplifier part II

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I, too, would like more input on loudspeaker design beyond Olsen and Beranek (our design 'bibles' 40 years ago). The simple models just don't 'cut' it completely. And what about honest transient response like the Manger speakers do?
 
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Do you really think this matters in the long run? Folks have toyed with this for decades, speakers are designed for ideal voltage source amplifiers I don't see any change coming soon. The auxiliary issues require some user intervention, I see this lack of plug and play a show stopper. Besides the point I don't see the THD per se as an issue.
Yes. I have heard convincing sound emerging from ordinary speakers, when other factors that are actually far more critical to allowing this to happen are dealt with - personally, I would see this as a major waste of creative and engineering energy ...
 
Do you really think this matters in the long run? Folks have toyed with this for decades, speakers are designed for ideal voltage source amplifiers I don't see any change coming soon. The auxiliary issues require some user intervention, I see this lack of plug and play a show stopper. Besides the point I don't see the THD per se as an issue.

You're right as usual. Me, I'm tip-toeing out the back door with Richard....

😎
 
Hi...
...Danley Sound Labs
What can i add ? A perfect resume.
I Will be not very talkative, because I am just resurrecting at the time of both an heart attack and the sin bin. (No connection ?), feeling like a 0% yogurt.
I tried hard in the 70Th with servo-ed speakers (double moving coils, captors in front of the membrane). Lot of work, interesting results on the paper, not convinced by my ears 🙂
My conclusion on the subject would be, "simple is beautiful" or let us try to find a new way to transform eclectic signals in acoustic ones than those paper cones, magnets and moving coils ...
Yamaha tried this too... they din't made a standard of this (see snake) technology.
 
Do you really think this matters in the long run? Folks have toyed with this for decades, speakers are designed for ideal voltage source amplifiers I don't see any change coming soon. The auxiliary issues require some user intervention, I see this lack of plug and play a show stopper. Besides the point I don't see the THD per se as an issue.

yes, i do. Folks have tried. Now we have SIm to speed things up and we have many more people - myself for one - who are not only interested in a flat freq response. The goal would be PnP. But as more and more speakers are going wireless, the amps Today will be inside along with the speaker to a larger extent.

yes, the wireless is not perfected for HiEnd... but it wont go away and is here to stay. So, improvements down the road will come. But that part is easier to have distortion lower than most speakers. This may be one of the last frontiers to become commoditised...... low distortion speaker/amps.

There really is no reason the amps Must be unstable with any load. Its just electronics. it will be overcome... it is pretty good already. Low distortion with amp like seen here is cheap and makes a big BIG reduction in acoustic distortion output.

But maybe all is just good enough now? Thats up to others to decide for themselves. I think some original new thinking with the people here and in other forums can do what wasnt able to be done many years ago.

Meanwhile, I'm listening to low distortion and loving it.


THx-RNMarsh
 
There really is no reason the amps Must be unstable with any load. Its just electronics. it will be overcome... it is pretty good already. Low distortion with amp like seen here is cheap and makes a big BIG reduction in acoustic distortion output.
The reason historically is because Big Metal is necessary. And that means Big Money - QED ...

Big transformers, big smoothing caps, big heatsinks. All costs bucks - therefore, that solution is a minor player. Yes, we have SMPS, class D topologies - but these are still struggling to get the SQ right, certainly at the cheaper end.

Smart engineering is required, but many people are entrenched in old, complacent thinking - "sharp" solutions can make it happen, but people have to be open to the possibilities ...
 
It now has a much better chance than a vinyl comback.......And Headphones.... wonder what this will sound like when done to a headphone amp?
Hmmm. Senn HD800 or the HiFiman HE500 as well as more modest headphones. I know what I am doing tonight.


THx-RNMarsh
 
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I made a model in the simulator for nonlinear suspension. It was tricky but if I have an accurate K() function for the nonlinear suspension I could plug it in. Curious about other distortion mechanisms I can try to model. Obviously it would be difficult to make it do certain things but it is certainly interesting to try.

I want to try the nonlinear BL modeling. The Klippel lecture Frank linked to gives some very helpful Bl plots, but I'm having a hard time modeling those curves with any function. The closest so far is something like log(10**x+10**-x+10**15), which resembles the graph nearly perfectly but I'm not sure yet.
 
I, too, would like more input on loudspeaker design beyond Olsen and Beranek (our design 'bibles' 40 years ago). The simple models just don't 'cut' it completely. And what about honest transient response like the Manger speakers do?

Hi John
The Manger is indeed good, the best driver i have ever measured.....so far as it's time and acoustic phase, it preserves the input waveshape. It's main weakness is a fairly high level of harmonic distortion which increases as the frequency falls and level increases.

It radiates and measures "as if" it were what Dick Heyser wrote about, radiation from a single point in time and space.

It preserves the input wave-shape very well, reproduces a square wave over a broad band also about the best i have seen, better than my synergy horns (which are multi way speakers).

John, i am out of hands on touch with circuitry but I have developed a number of transducers and speaker systems and have had a TEF machine since the tef10 came out and it has helped guide my path so to speak;

https://www.google.com/?tbm=pts&gws_rd=ssl#tbm=pts&q=thomas+danley

I can take a try answering a loudspeaker question or two if your willing to accept a "here is the way i see it" answer.
Best,
Tom
 
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