audio-talk

Ray P wrote: ↑Mon Jan 11, 2021 7:42 amBump

Hi Ray, am I right in thinking this should support up to 192kHz/24bit (with the right USB to i2s interface) ?

Cheers.

Heh, right now I reckon there's a 60% chance of it lasting, 40% that I have to break into the new reel. Quite relieved that I was still able to get hold of it as it's not 'green'. I settled on it years ago as it gave consistently better joints over everything else I'd tried (including the Cardas sol...

Sooo... sweepstake on whether this reel of solder lasts until the end of the project. I *think* this dates back to 2003.

I do have another reel of the same stuff, thankfully.

The AD2 looks like a '" 'andy bit o' kit " as my Grandpa used to say. It really is, I've been very impressed with it. Some hackaday write-ups have complained that it's not all that accurate into the Mhz region because of the poor quality test leads etc, but for our purposes it seems absol...

OK, I learned a couple more functions of my AD2 today. Firstly the frequency sweep, which I set to go from 10Hz to 100kHz, 2V amplitude. I ran the same test with offset set to 2mV, 0mV and -2mV. These settings corresponded to multimeter readings of 0.3mV, -1.7mV and -3.6mV obtained before the freque...

All I will point out is I would not look at sine waves, I would meeasure a frequency sweep if it can do that or a number of spot frequencys if not. And I would look at a FFT of the sine wave, if you can see distortion its up close to 1% Thanks Nick. I know the frequency generator will do a sweep bu...

OK I did some testing with the multimeter and the Analog Discovery - this is really quite a nice bit of kit. Turns out that I could simulate a DC offset on the waveform generator, although at the millivolt level it wasn't all that accurate - the AD itself seems to have a bit of an offset on its outp...

Interesting - I went for series connection because I had plenty of headroom in the preamp, and I figured I'd get better performance. When I built the last amp, after installing the input transformer with its load network, I scoped both phases on the secondary to make sure they were equal, and all l...

I noticed you say the input is connected in series but the datasheet shows parallel connection for phase splitting. I tried series input connection on my 1676, and the phase splitting performance was all over the place between the two outputs compared to driving the input coils in parallel. Interes...

It doesn't sound like much. I think the bass would be affected first. It should really quantified, so people know what they're working with. Exactly, it would have been nice if this had been documented on the data sheet instead of buried on the internet for me to find after I'd spent the money. It'...

In the middle of building up the second of the 300B push-pull monoblocks, and I come across an Audio Asylum post regarding the Lundahl LL1684 input transformer I chose for the project. It's a small amorphous core low impedance transformer, that I selected to match the low-Z output of my preamp (66 o...

Heater wiring - probably my least favourite part of any build, now done. Also the transformers are all connected up except for the HT secondaries (red and red/yellow wiring). The unconnected black wires are from the two chokes. https://user.fm/files/v2-8f07374667e589a00ead850717437cd6/P1140121.jpeg

Also, if anyone is having issues viewing the images can you please PM me, as it seems some configurations might be blocking them. Ta!

Some more pics of Channel A final build after setting up on a shelf behind my desk / bench under some strip lights, to refer to when building the second. The signal section: https://user.fm/files/v2-207687d3efc35933006c908b7d2853a0/P1110118.jpeg and the power supply section: https://user.fm/files/v2...

Quickly powered it back up on the bench as I wanted to actually record the voltages and also re-run the scope tests to measure the gain. Here are the voltages, the first figure is that predicted by Spice and PSUD, the second is the actual: Output stage B+ 467V / 471V 300B Plate Phase + 460V / 467V 3...