Udo (Zucker). Lives in Portugal these days.I knew the ex-Bosch engineer really well from F1 but can not think of his name at the moment.
Udo (Zucker). Lives in Portugal these days.I knew the ex-Bosch engineer really well from F1 but can not think of his name at the moment.
Yes, Doug did the TMA amp designs.I read that was a Douglas Self design. Was that correct?
Of course, thanks John.Udo (Zucker). Lives in Portugal these days.
I think there are a few sweeping statements there.So far, class D amplification is problematic with tweeters, at least the old class D.
When I was n-reviewing the specifications and measurements of the IcePower 1200AS2 module PDF manual, the only graph I found different was that of the phase. That it varied so much was an alarm signal in my brain.
This would explain why unaltered voices (you know, without Autotune, vade retro satana) and acoustic instruments sound bad with this technology.
Many audiophiles reneged on the NC400, which is why I supposed that he also had a big problem with the phase. They have the problem but it is not that huge. Maybe the NC500, with custom buffers mask that problem.
With the current music, so badly recorded and manipulated should not be problematic. This would explain why many do not dislike sound. Let is face it, what percentage of people listen to (high) quality recordings with acoustic instrumentation and unaltered voices via software? And with DR > 11dB. The percentage must be ridiculous.
I'm also keen to see the transient overload characteristics of these modules. Alan is going to do some toneburst testing on his at some stage so hopefully we may get to see what happens in gross overload and/or on the edge of clipping.
I too have lost tweeters in a split second when a high powered amplifier had an out-of band-oscillatory burst.
Back in the day, I inspected many tweeters (performed autopsies) to determine whether they were valid warranty claims or not. In my experience, around 40% had vaporised lead-in wires and undamaged voice-coils, with no evidence of long term heat damage. They were the audiophiles with their dynamic CD sources and high powered amplifiers that in my opinion were bursting into oscillation at transient overload. Often they would have repeat failures. Changing amplifiers sometimes solved the problem.
The heat damaged ones were the AC/DC guys who played loud all night after drinking a bottle of bourbon.
It was after inspecting many expensive dead berrylium tweeters, I decided to repair a few just for fun by unwinding one turn of the VC and resoldering to the lead-in wire. Many of those repairs never came back and never cost their owners a cent. (NS-1000 tweeters were around AU$200 at the time).
In fact, one of the tweeters in the NS-1000Ms (Japanese import 10th Anniversary model (1984)) at my father's place is still going 20+ years after I did the same repair. We do have a brand new one in case it ever fails however.
I hope the speaker systems in use here are single-driver crossover-less types that have no phase distortion.So far, class D amplification is problematic with tweeters, at least the old class D.
When I was n-reviewing the specifications and measurements of the IcePower 1200AS2 module PDF manual, the only graph I found different was that of the phase. That it varied so much was an alarm signal in my brain.
This would explain why unaltered voices (you know, without Autotune, vade retro satana) and acoustic instruments sound bad with this technology.
Many audiophiles reneged on the NC400, which is why I supposed that he also had a big problem with the phase. They have the problem but it is not that huge. Maybe the NC500, with custom buffers mask that problem.
With the current music, so badly recorded and manipulated should not be problematic. This would explain why many do not dislike sound. Let is face it, what percentage of people listen to (high) quality recordings with acoustic instrumentation and unaltered voices via software? And with DR > 11dB. The percentage must be ridiculous.
Yes, a factor as well. I mentioned in Post 182 above.I have not really followed, too many other things going on... A quick comment on phase: there will be latency through the amplifier (group delay) in addition to a phase shift due to the output filter. Group delay is the negative of the change in phase over frequency. If it is constant, phase shift will not change the timing (pulse response) of the signal thus is benign. This complicates the whole phase issue -- you want to know the constant delay that is independent of frequency and separately the phase shift over frequency at the output. Have to be able to do phase separation, natch. Or just plot group delay instead.
Please forgive if this has already been said or does not make sense, only skimmed the last few pages.
@dreite, my second audio system works with my tweaked and modded KEF Q100, 5.25" coaxial speakers, with two first-order filters.
Like almost dynamic speakers, the phase went progressively / smoothly in a range: 0º - 45º with which the human ear will hardly appreciate that variation.
with resultant phase shift of (approx.) 180 degrees around the crossover point.
I have a lot of docs about KEF Q100 and others coaxial speakers (KEF or not), in open and closed Internet (with much more info in a forums where I write). But it is not the thread, and most likely my comments are deleted again.
If I am not wrong, ALL Qx00 series uses first order filters.
http://maty.galeon.com/WP-imagenes/kef-q100/KEF-Q100-impedance-phase.png
Open a new thread.
Off course they are not the same, that is why I wrote to the manufacturers!!!
*** If you want to continue, open a new thread ***
Re phase, just have a bit of a think about what your speaker does to phase. It ain't pretty.
Here is that:Well it's simple to confirm with a (filter less) scope measurement.