London Grammar 'If you Wait' and some Steve Gadd before that.
I try to buy once a week - mostly on Amazon. I think I have about 600 or 700 CD's and maybe 200 LP's. I have a premium Spotify account as well for casual listening.
I buy vinyl too - especially jazz. But Amazon can be dangerous for vinyl - I've sent a few back.
Surely even if the driver cannot reproduce it, the HF currents still flow through the voice coil = I^2.R losses?
You forgot to add that (decent) relays are also an altogether better performing solution than a Shalco switch which tarnishes and is exposed to the elements.
Thanks for the link. However, it addresses DC offset, not high frequency.
So the question still remains, how does very high frequency content cause a DC offset of any coil? There would have to be rectification after the tweet crossover.
Agreed. Unanswered is how much very hf current will there be given the tweeter inductance. But IR loss is to be worried about.
A friend, at his church they used a snake cable to bring the mikes to a mix board, and used two of the same snake lines to bring the speaker signal back to the stage instead of line level to a stage monitor amp.. I'm sure it wasn't a really high bw amp, but the tweeters and the tweet crossover were totally fried even though they heard nothing..so it would have to be 20+Khz oscillation.
jn
One thing to remember about JBL M2 is the stock configuration uses two Crown class-D power amps with internal DSP. The DSP handles crossover and speaker FR corrections. It also digitizes analog inputs to the DSP, then converts the digital back to analog before sending it to the power amp stage. So, everything that comes out of it is played back through its DAC, and possibly gone through ASRC if it were digitally input at the wrong sample rate. Listening tests with test subjects sitting in the middle of some room perhaps with curtains hanging in front of the speakers may not be the same thing someone would hear in the near field and lower volume levels. Also, the horns do have a sound, IMHO, but it is pretty neutral, nothing to complain about.
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I use Panasonic AGN mini relays. They are rated for 50 million mechanical operations at no load - which is as near as dammit to what a line level audio signal is into a 10k Ohm load. Best of all, the distortion measures at about 2ppm - I cannot measure lower than that with my test gear (Quant Asylum 401).
For speaker switching, I think a mosfet relay is the way to go.
So you mean that all violins should really be rebuilt because the earbrain reacts to a linear sound source according to the M-F curves?
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A question to all:
Has anybody ever tried to record ultrasonics using a cell phone?
If so, did the phone react by simply reducing it's gain, did it create subharmonics due to undersampling, did it do nothing?
Do all cell phones use the same mems unit for a mike, or are vendors all over the place?
Do different phones use the same sampling rate or are they also different?
jn
Has anybody ever tried to record ultrasonics using a cell phone?
If so, did the phone react by simply reducing it's gain, did it create subharmonics due to undersampling, did it do nothing?
Do all cell phones use the same mems unit for a mike, or are vendors all over the place?
Do different phones use the same sampling rate or are they also different?
jn
None of the above, but I have seen hi-end reviewers using iPhone apps to calibrate and set levels.
Me Mr. iNothing.
In my case because I've ended up with an overly complex implementation
lol..... I hate anything emech...
Why not use a mix of very low frequency (for the boomer) at higher level, and a 20KHz for the tweeter ? Just to break the suspensions and avoid neighbors complains ?
At my age, it seems not reasonable to wait one month ;-)
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Use a pink noise source. I hope you enjoy yours. They are not very efficient, so you will need a bit of power to drive them.
You mean like a CD player?
I could simplify things but then I would have to replug things when I wanted to change which turntable I was using, which is annoying. I just wanted to make something that was easy enough for anyone to use unlike my usual constructions where I never actually get around to labelling anything and even I forget what random knob 3 does.
Time constraints means that phase one WILL end up being the replugging method of course. I requested a patchbay and that was refused by the planning committee...
Amazon is great for CD's, lots of bargains. I haven't got any paid for accounts but I use Deezer's free site which is great for discovering stuff and their selection is growing all the time, they've recently included Of Human Feelings by Ornette Coleman which I could only find odd tracks on YouTube and is otherwise like rocking horse s***
That's basically what I do, saves having to worry about switch and relay distortion too
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