I'm running 2 A10 in parallel for ~4 ohms.
Already running P/S at 20v based on my reading in this thread. Thanks for the summary of other mods. I have some Roederstein bipolar 2.2uF 63v and Russian mylar 2.2uF 63v that I will try on the inputs, and some ceramics for bootstrap. Cheers.
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I don't think input capacitors really affect SQ that much. The MKP already have low distortion, but they are strangly marked for the position, that is true (X2) but weak point didn't really improve much when I tried.
If I compare my boards, hiampmini with wurth 10uH and YJblue, main difference remains after helping YJblue powersupply a little (hybrid Panasonic or silmicII//0.1uF position), it is lowlevel information. Here YJblue still loses very much. Listened on MarkAudio P70 Gen1. lowlevel could be people walking during recording, all kind of little sounds that should not be in the musicrecording but are 🙂. YJblue filters away those sounds almost completely. Listen to those little sounds and YJblue will puzzle all of you a lot.
Many of those ambient sounds that accidentally get in a recording like walking, feet shuffling, chairs creaking, audience coughing, sheet music rustling,all depend on how well your speaker reproduce the full range. I hear those sounds just fine on my YJ Blue/Black or Ybdz Wiener, or DUG's amp. With DUG's amp being the best and YJ Blue/balck and Ybdz a tie. There is a sound that is feet walking on a wooden stage floor (very deep and gently thump) that I did not hear until I connected a good low distortion and efficient subwoofer that reached 30 Hz. When I hear those sounds in the recording, I mistook it for someone actually walking around upstairs on the wooden floor.
The biggest part missing for me with the (not yet modded) YJ blue/black is "realism" in the mids and highs. Stereo separation is terrible and anything from male vocals up to cymbals sounds like it is playing through a paper towel tube. No sound stage or imaging to speak of. Just hollow and dead. My ~70-year-old mother and father were visiting last night. I asked my Dad what he thought of the sound, and he hesitated, then my Mom pipes up from the background and says "It sounds like mono. Like back in the old days. You can tell those guys on the chat room or whatever that it sounds like mono." She didn't mean this as a compliment. The 11 and 12-year-old ears agreed. "That just sounds bad, Dad."
Anyway, I am really glad that I chose a board that is easy to mod. 🙂
Anyway, I am really glad that I chose a board that is easy to mod. 🙂
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I would say listen again and now just listen to those little sounds, some of us here in the Netherlands did and the difference is huge, i am not alone in concluding YJblue has serious problems for HIFI listening. Nothing wrong with that, it is just not HIFI.
Agreed. Did you find you could raise it to HIFI quality with mods, or am I wasting my time?
There is something off there. Maybe a bad board but I have not had a 3116 sound anything as bad as you describe like muffled and mono. One time I had a similar experience with sound from my PC and it was something in the sound card settings that got messed up. It sounded just like you describe mono, dull, like a cheap AM radio. It had to do with a checkbox in the driver that lets the system take control of the soundcard. Rebooting fixed it. Not saying that is what you are hearing but I have experienced something similar.
Ok I will listen again. Out of curiously does anyone else have issues with the YJ blue/black board not sounding hifi? So far I have heard Irrebeo and Cogitech. The popularity of this thread is some testament to the general good sound of this amp. I have been following this thread from day 1 and do not recall many other bad experiences. Please chime in if you have a bad experience from a sound quality perspective.
It is definitely the board. When I switch to the tube amp or STA508 "on the fly" without changing anything else, the sound just opens up and all the clarity, sound stage, imaging and "realism" just pours back into the room. The difference is not subtle in the least.
Do these boards require a lot of "burn in" or something? I did notice that it had opened up a bit this morning after letting it run all night at low volume. Still bland, but it does seem a bit less annoying now - not quite as "mono". I'm generally not a believer in component "burn in", so I hesitate to draw any conclusions.
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Perhaps YJ has started sourcing lower quality components for these. Maybe that's why they are on sale? Just guessing.
My experience on the Blue/black is that the sound stage is kind of flat and the highs are still a bit harsh hoping to fix all that. I will try the ChengZhi board see it there is any difference.
I have replaced the original boot strap cap from .1uf to .22uf V BC film cap.
I have replaced the original boot strap cap from .1uf to .22uf V BC film cap.
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The only problems I've heared with YJ so far are cracks and pops in loudspeakers (s/n 89db), that are realy something undesirebale!
Once I placed protection (1) board in between the cracks gone, but now can't turn the preamp. Volume (50k) higher than 9 o'clock. Needs two, but now can't find data/manual/other forum members insight how to properly paralell those.
Other than that sound on default untouched board is great (via tube preamp though).
However, I might give up on it and jump to build new config. with Audiobah's, that has 22uH inductors already (better to my 8 ohms) and spk.protect.
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Regarding the YJ blue/black; why are there 2 input caps per channel (large and small) and should I replace all of them?
An externally hosted image should be here but it was not working when we last tested it.
wow, this thread is dynamic!
i remember those good old days, when almost everybody was impressed with the red yj.
then its designed was bad with the components too far away from each other.
then came the black-blue yj.
folks were impressed again.
is the hyper over, or what is this.
there are other cheap class d boards, too.
so it cannot have been all about the low price.
i remember those good old days, when almost everybody was impressed with the red yj.
then its designed was bad with the components too far away from each other.
then came the black-blue yj.
folks were impressed again.
is the hyper over, or what is this.
there are other cheap class d boards, too.
so it cannot have been all about the low price.
Sounds like you have Jamicons electrolytic capacitors (TL type productioncode was 944C0) still on pcb. Those were replaced befor we listened seriously. I mean 2 people had heard the boards completely standard (may2014 deliveries), so two boards, with the Jamicons and, and I was told my clockradio may sound better, burning in didn't help 😀
We listened to the Adagio part, 2nd on this cd, some reviewers say there are no backgroundnoises, so they may have listened to YJblue too🙂
Brahms: Violin Concerto; Sonata No. 3 by Daniel Barenboim (piano), Maxim Vengerov (violin), Chicago Symphony Orchestra, Daniel Barenboim (conductor) - New, Rare & Used Music Online at Alibris Marketplace
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If you change value you need to replace both. But that isn't the difference you are looking for, I am sure.
Hey, I only replaced the big ones - what happens if you don't change the caps that are connected to ground. They are connected to ground - does it really matter that the values match?
short time ago somebody tried and mentioned it here I think. increase in pop sounds maybe, or decrease with equal values? TI mentions impedance should match and therefor they should have same value, but to ground or to source is likely to differ I think. maybe charging/discharging times will vary more with unequal values, having 2 pops instead of 1???