You have to provide a 20V pre-regulator in front of the LT1963. At least one transistor with a zener diode. Or LM317.
Hello Friends, did someone ever took the burden of measuring DC resistances for pins in a (working) tda1541a ? What I have is 100% original, but doesn't seem working.
Thanks.
Thanks.
So I decided to go all out and power the USB module with two PSU2-Mini and separate transformers. It's getting crowded in the case! Added a little stick-on heat-sink to the board providing the 400mA. Seems to be working well... Sounds absolutely fantastic! Thanks a lot to Miro and everyone on this brilliant thread 😊
Ah and I also added TH || cap ground breakers.
Ah and I also added TH || cap ground breakers.
Been using the LM6171 and very happy so far…. Still researching other opamps. So many choices.
Is there any super compact discrete I/V (SMD)?
Is there any super compact discrete I/V (SMD)?
The OPA1655 is 85% of the Sparkos/Burson sound for 7% of the price. An additional 15% costs a lot. 😁
If you want a little more progress, you have to make tube I/V. This is my subjective opinion.
If you want a little more progress, you have to make tube I/V. This is my subjective opinion.
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What can you tell me about opa1611? I purchased a used pre phono, on second stage has this. Would like to swap for ad1655, and ad797 in the first stage... Thoughts?
Could you be more precise - where do the 2x 47pf go?
I've been trying out a small number of op-amps in the first stage of my PCM56 DAC. Best so far is AD845. I'm very pleased with that. AD843 wasn't happy in my particular chi-fi board - distorted treble, though otherwise good. May have offset issues. LT1363 was quite a bit less good than AD845. To come I have OPA1611 and AD797, waiting for a friend to put them on adapters. I have just one OPA627, expensive to find a mate.
I'm most interested in trying the AD 8** range of chips, since the AD845 sounds so good. AD811 is hard to find and AD844 also. I'd like to try AD8065 but that's 12+12 supply or even 10+10. AD825 maybe also. AD847 has offset issues it seems, like AD843. It's mainly about the availability of genuine chips and fixing offset and oscillation issues.
Some discussion of these AD*** op-amps would be welcome.
I didn't try that, I decided on tubes, since I have various ones, some transformers for that and a lot of parts for power supply. The OPA1611 sounded a bit too bright and sharp to me, maybe because I like a lot of bass, and with that, there isn't too much of it. For the OPA1612, I tried adding an IRF510 source follower to the preamp, and it sounded better like that. It corrects it a little, as it forces opamp to work into class A and single ended. When I tried the same thing with the Miro DAC I/V, the result was not so good, so I gave up.
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Between pins 6-8 of ad797 should be 47-50pf. It's is used to lower distortion.
https://www.mouser.sg/ProductDetail/Analog-Devices/AD844ANZ?qs=/tpEQrCGXCz0X1ElpJpMhQ==
https://www.mouser.sg/ProductDetail/Analog-Devices/AD811ANZ?qs=/tpEQrCGXCwyaTcANUKIlg==
I bought from Mouser.
Digikey has both of these too.
page 17 of 19. Figure 54 of the datasheet. Skip C1 if not needed.
I don't know what to expect with that replacement. Only a test can tell, but with an oscilloscope, it is a must.
This is an example of putting famous signetics ne5534 directly in miro dac. Oscillating like crazy. Without scope you may not notice if not experienced. There are few that used it and liked the sound. I listened to it for few minutes and bloated huge bass, muddied mids and highs was a telltale sign to turn it off and turn on oscilloscope. Some find it vintage and pleasing.
So for diy hobby, oscilloscope is a must.
So for diy hobby, oscilloscope is a must.