That I am sure
Definitely. Documentation is good.
I hope so. Have not own any before
Not sure what you mean
Well, that's subjective. I have to find out personally
Of course they can be tested. The test points are really convenient though
No use to me. I do not intend to upgrade it. When the next generation chip comes out, I'll just get the new one.
See above
At the discounted price, I totally agree
I hope so. I guess it depends on where you located
Nothing I can think of right now. Will let you know when I have questions.
Thank you!
Regards,
Hi guys
I expect this chip is dumping a broadband of noise so in fact the regulators' noise performance is perhaps somewhat irrelevant. But what about impedance into the gates for the 12V supply? Would a lower impedance (than LM2937/40) benefit dynamics? I plan to find out! I have a very old scope that I don't know how to use (!) but I will dust it off and connect it up to the amp's test points, post what I find, etc. Just bear with me, I have a job, wife, etc, motorcycles, etc. Distractions from my true calling - to break perfectly good bits of kit and call it an upgrade ;-)
BTW, do please stop saying this amplifier is excellent cos Ti made it and it tests so well. Look at the audio coupling caps, 2 pairs of them. 40 cent Panasonic aluminium crap. In the signal path. Like eating a candy bar with the wrapper on. Noooooooooo !
I expect this chip is dumping a broadband of noise so in fact the regulators' noise performance is perhaps somewhat irrelevant. But what about impedance into the gates for the 12V supply? Would a lower impedance (than LM2937/40) benefit dynamics? I plan to find out! I have a very old scope that I don't know how to use (!) but I will dust it off and connect it up to the amp's test points, post what I find, etc. Just bear with me, I have a job, wife, etc, motorcycles, etc. Distractions from my true calling - to break perfectly good bits of kit and call it an upgrade ;-)
BTW, do please stop saying this amplifier is excellent cos Ti made it and it tests so well. Look at the audio coupling caps, 2 pairs of them. 40 cent Panasonic aluminium crap. In the signal path. Like eating a candy bar with the wrapper on. Noooooooooo !
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Hi guys
I expect this chip is dumping a broadband of noise so in fact the regulators' noise performance is perhaps somewhat irrelevant. But what about impedance into the gates for the 12V supply? Would a lower impedance (than LM2937/40) benefit dynamics? I plan to find out! I have a very old scope that I don't know how to use (!) but I will dust it off and connect it up to the amp's test points, post what I find, etc. Just bear with me, I have a job, wife, etc, motorcycles, etc. Distractions from my true calling - to break perfectly good bits of kit and call it an upgrade ;-)
BTW, do please stop saying this amplifier is excellent cos Ti made it and it tests so well. Look at the audio coupling caps, 2 pairs of them. 40 cent Panasonic aluminium crap. In the signal path. Like eating a candy bar with the wrapper on. Noooooooooo !
I agree with you, I would pull out any ecap in signal path without a second thought. Believing Ti use the optimal "sounding" circuit/parts for their stuff is like believing opamp I/V is the best I/V ever
BTW, u can try audio transformer for the +/- input without any coupling caps. I use them in Gmarsh Wiener and Wiener Pro (3250) and it improves the sound quality.
Is your Sigma 11 the old version? It had a problem of the output power trace too thin thus limiting current flow. Did u add a thicker wire from the 0.47R to output?
No idea what version it is but that's a good idea - short fat cable straight off the pass mosfet/resistor into the amp
I agree with you, I would pull out any ecap in signal path without a second thought. Believing Ti use the optimal "sounding" circuit/parts for their stuff is like believing opamp I/V is the best I/V ever
BTW, u can try audio transformer for the +/- input without any coupling caps. I use them in Gmarsh Wiener and Wiener Pro (3250) and it improves the sound quality.
The amp has DC on its input pins so do I need to block this DC into the transformer? I assume not ... but it's better to check assumptions...
Hi Lo_Tse, I would encourage you to upgrade it according to the TI app note! The output inductors dominate technical performance. Replacing them with the TI-recommended Wurth inductors should be audibly better.
I have had great success in upgrading from stock inductors on several TI class D amplifiers.
Best regards,
Mike
Hmm, 0.005% vs 0.003%, mit sure if hearable.
Maybe not. I should have written "happiness" instead of "success"
There is DC of either + or - input with reference to ground, but if you measure across +/- input, there is no voltage differential as both have the same voltage, thus no DC.
Hi all - I fitted the transformers. I removed the second set of coupling caps and connected the pads to twisted pairs into the transformer secondaries. I managed to invert the phase on one of them but that was easily corrected. The sound is more open and spacious and would be excellent but for a little too much sibilance -it is noticeable but not nasty, and it's a little more than I consider natural. Perhaps my source doesn't like this load? I see there is a low pass 100r and 100pf on the input side - did anyone modify this?
Thanks...
Thanks...
Did an interesting comparison between the 3251 EVM and the 3244 EVM. The 3251 is more sibilant and glassy in the 2-6kHz range. The 3244 is more even and nicer to listen to.
I will continue with the 3244.