Improving S/N, as already stated. Also improving ratio between useful signal and hum/buzz voltage, that is created by leakage ac currents (capacitive or ground loop) as a voltage drop across SE cable shield and this unwanted voltage is independent of useful signal. The bigger the ratio useful signal/shield interference voltage drop, the better.Would you mind explaining why maxing the volume on the dac and turning down the amp makes a difference, and why this is more important for unbalanced interconnects?
Yes but he speaks about 300kHz BW. This is a nonsense in any kind of recording. I do not need to search, I know how high do B&K special mikes go. Still below 100kHz. And how is it going to be reproduced?? This 300kHz / flat phase request is an utter nonsense.search utub for "binaural". they use special dual microphone setup with "human-like" ears. it works. u-tub usess 88kBit AAC - but it still works!![]()
Quality control poor or missing, I have already mentioned it (when inspecting the teardown photos).
To be honest, I don't mind it - it is a simple fix - I just want to confirm that I won't void the warranty.
This is not legal.and the manual makes it very clear that the warranty is "instantly" voided if you open it.
Sounds great, though I wonder which good options for volume knobs there are which are large and tactile.License the DSP from Dirac and call it a day. Get rid of MQA altogether. Improve the volume knob to something large, tactile and iconic that would generate envy from non-audiophiles and you'll have an international hit on your hands.
Sounds great, though I wonder which good options for volume knobs there are which are large and tactile.
Bit off topic on my part though.(Can't be worse than another 5 pages of subjectivist vs objectivist arguments...)
Here's a TPA3255 module with passive PFFB, I increased the negative feedback from 6.9dB to 11.4dB. Gained some 4dB on 1kHz THD+N.By the way, I could be wrong and the PFFB is passive (PPFFB) but perhaps higher order than 2nd. As long as the input (into the PPFFB) can be driven high enough (say 10Vrms with frontend OpAmps running from +-15V) the feedback factor can be increased significantly but limited of course by the 21dB "open loop" gain of the chip.
...and it becomes even more tricky if some traces blew up with the fireworkSome SMT rework to remove the dead TPA3255 and replace it worked well but it is not a job for every DIY’er.
Thanks for sharing this. As expected, 4dB more feedback (7dB to 11dB) reduces distortion by an equal amount. This will lower the gain as well, probably down to circa 11dB now. So preamp gain will need to increase by 4dB to keep amp output the same.Here's a TPA3255 module with passive PFFB, I increased the negative feedback from 6.9dB to 11.4dB. Gained some 4dB on 1kHz THD+N.
My funky spectrum analyzer might be a limiting factor though.
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Yep. I have seen craters left behind when a GaN FET goes ballistic....and it becomes even more tricky if some traces blew up with the firework![]()
I can't stop laughing. Thanks a lot.Yep. I have seen craters left behind when a GaN FET goes ballistic.
It looks modest. But so do I. Put it inside a box labeled Tiffany & Co., or one labeled Heckler & Koch GmbH, or one labeled Hermes. Soon these amps will be so small that they'll fit into the box you get when you buy a Rolex. So is the significance of this product that high audio performance per our (ASR) standards can be attained using a Class D chip that is reasonably priced and available as opposed to the current class of high performance class D amp modules (ICEpower, Hypex, Purifi) that are more expensive and are significantly larger in size? Some of the functions done on the circuit board of the Hypex and Purify modules are done in the Class D chip thereby reducing the size of the implementation. Again, I assume chips like the Texas Instrument Class D chip(s) are developed for broader market use beyond the consumer audio products.
Thanks for testing this one !
I was wondering: you test output impedance for headphones amps but not for speakers amps.
Is there a reason?