The goal of the transformers is to not change the sound and provide passive “natural” filtering and galvanic separation as free gifts. All in a simple appearing but in reality complex way 🙂
Without feedback and necessity for opamp rolling and low noise PSUs too and balanced/unbalanced conversion (if desired) the uncomplicated way.
In general this leads to pleasant results and an empty pocket. Matter of taste and predefined preferences too. The DAC Meisters likely will prefer best measuring opamp circuits. Please don’t mention intersample overshoots and noise skirts.
Without feedback and necessity for opamp rolling and low noise PSUs too and balanced/unbalanced conversion (if desired) the uncomplicated way.
In general this leads to pleasant results and an empty pocket. Matter of taste and predefined preferences too. The DAC Meisters likely will prefer best measuring opamp circuits. Please don’t mention intersample overshoots and noise skirts.
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However, the frequency response and non-linearity of the core should be mentioned.
Alex.
I would be tempted to try anyway....
That said, it might be stupid, I would feel like I'm going back in time... 😀 😀 😀
Hey Jean-Paul!
I have a lot of reading to do. I just bought one new to replace a dead Topping E30 II light. It didn't last very long (the Topping).
I think you may have been better to use a USB isolator or optical if you have ground issues. I have yet to read how you were connecting the data source. I have found some USB power supplies are pretty noisy as well.
I have a lot of reading to do. I just bought one new to replace a dead Topping E30 II light. It didn't last very long (the Topping).
I think you may have been better to use a USB isolator or optical if you have ground issues. I have yet to read how you were connecting the data source. I have found some USB power supplies are pretty noisy as well.
Bummer. I just bought a two week old Topping E30 II Lite, albeit cheap as the owner didn't like it.
My other two Topping units are fine. Different models.
They are a pain to take apart. You need a 12cm 2mm hex tool to reach the front cap screws through channels. I found one for about $17, but I won't buy a special tool for this one job. I did get it apart, the audio supply is not turning on. Why? No idea without schematics. They won't release them of course - like anyone is going to steal their design and produce their own. That just isn't worth it.
I'll probably poke around with it checking obvious things. It died and always acted funny before that. Build quality is good, I won't take that away from them. It was made to discard if it ever acted up. Like most things these days.
They are a pain to take apart. You need a 12cm 2mm hex tool to reach the front cap screws through channels. I found one for about $17, but I won't buy a special tool for this one job. I did get it apart, the audio supply is not turning on. Why? No idea without schematics. They won't release them of course - like anyone is going to steal their design and produce their own. That just isn't worth it.
I'll probably poke around with it checking obvious things. It died and always acted funny before that. Build quality is good, I won't take that away from them. It was made to discard if it ever acted up. Like most things these days.
I may have overlooked the info here, but on my unit, I was able to identify a PCM9211 - hence there's only one sample rate crystal.
I don't have a macro lens, so on the photos only the "BB" logo is barely visible, but with magnifying glasses I could clearly read PCx921x. That leaves only the PCM9211.
I don't have a macro lens, so on the photos only the "BB" logo is barely visible, but with magnifying glasses I could clearly read PCx921x. That leaves only the PCM9211.
Hi Anatech. I think I just made the first balanced outputs I ever made myself a tad too simple. Haven’t looked at the device for some time but tomorrow parts will arrive for the tiny PLL PSU.
This SU-1 in disguise was only made as an excercise when being ill/healing. I do like it and have to finish it.
Crystal at 39-40 pins, PLL filter at pin 43 - looks like 9211.
(BTW - very nice chip, good SPDIF receiver and bus routing, I often use it, but I am surprised by such a small number of bypassing capacitors on its power pins).
Alex.
Good find by weissi! Maybe not enough decoupling (maybe there are decoupling caps at the other side of the board?) and other life threatening imperfections but it performs a lot better than it costs. After all this is a 79 Euro DAC and things should be looked at in perspective.
Let’s say many would not have bought anything else for a while if this one would have been available 10 years ago. With the updates it is sonically better than my 2 x ES9038Q2M based Eversolo DMP-A6. Because of the results I thought to design an internal AK4493SEQ based DAC board for use IN that Eversolo. Still contemplating. Now AK4497VSQ will be launched that seems a good candidate. The small differences in DAC chips sound quality don’t motivate to put much time & effort in it though.
What does your DAC cost, Alex? Just curious.
Let’s say many would not have bought anything else for a while if this one would have been available 10 years ago. With the updates it is sonically better than my 2 x ES9038Q2M based Eversolo DMP-A6. Because of the results I thought to design an internal AK4493SEQ based DAC board for use IN that Eversolo. Still contemplating. Now AK4497VSQ will be launched that seems a good candidate. The small differences in DAC chips sound quality don’t motivate to put much time & effort in it though.
What does your DAC cost, Alex? Just curious.
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I grabbed my USB microscope from work, but the photo of the PCM9211 doesn't improve that much (not that it matters, it's a 100% that type).
Could anyone help me identifying the muting IC "A806" here:
Could anyone help me identifying the muting IC "A806" here:
I want to use the SU1 (temporary) directly with headphones (replaced OPA1612 with OPA2156, will replace the +-12V SMPS with a XP IR0509S soon). I don't think that muting IC is doing anything good there, I couldn't care less about any intermediate noise between tracks).
OK, if that thing is anywhere near the SGM4807, it can stay.
OK, if that thing is anywhere near the SGM4807, it can stay.
New china muting IC to me. On paper about ideal, in reality I would rather see other sorts of muting.
https://www.wecorp.com.cn/UploadFile/201612120130099809.pdf
Replacing the SMSL branded +/- 12V switchers for about the same or maybe even fully the same switchers with 50 mV ripple till 20 MHz (yes that is 50,000 µV of ripple)? Really?
Linear regulators for this ultra low power application are much better with guaranteed below 50 µV ripple range. Even recent 78xx/79xx would do a pretty good job 🙂
https://www.wecorp.com.cn/UploadFile/201612120130099809.pdf
Replacing the SMSL branded +/- 12V switchers for about the same or maybe even fully the same switchers with 50 mV ripple till 20 MHz (yes that is 50,000 µV of ripple)? Really?
Linear regulators for this ultra low power application are much better with guaranteed below 50 µV ripple range. Even recent 78xx/79xx would do a pretty good job 🙂
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Jean-Paul, the IR0509S is the best DC/DC converter you can get from digikey in this case size, it costs €12. (not even the §§§ Ricolas (R) can do better).
I don't think the original one comes anywhere near it.
I have my reasons to stay all-internal at the moment (might change in the future).
With +9/-9V i get more current for headphones, while loosing nothing in terms of dynamic headroom. Of course I take care the source 5V will cope with the demands.
I don't think the original one comes anywhere near it.
I have my reasons to stay all-internal at the moment (might change in the future).
With +9/-9V i get more current for headphones, while loosing nothing in terms of dynamic headroom. Of course I take care the source 5V will cope with the demands.
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The new one is garbage too (imagine telling granddad that you made a PSU for a headphone amp with 50 mV ripple 🙂) but both will benefit from the onboard CLC filter. Easily bettered by literally anything low range linear though. I made a set of boards for such (SU-1) with a toroid and built it last week. It has 4 voltages from 4 separate windings but I did not implement it yet. Made a thinking error by not including regulators. It should have regulated 5..6V, and 3 x 3.3...5V. The idea was to have separate supplies for the relevant sections but I mixed up stuff with another project. Probably also because of other stuff coming inbetween. It happens.
Already corrected but I announced a stop on financial audio expenses for 2024.
😀
Already corrected but I announced a stop on financial audio expenses for 2024.
😀
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My SU-1 was about $100 CDN from AliExpress. It'll probably arrive in about 1 1/2 weeks now.
lol! Me too! Just in time.
