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penmarker

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Everything posted by penmarker

  1. Kenrick Sounds make amazing restorations. And their discipline while moving the speakers is commendable. But those people complimenting how good they sound through Youtube, and then through their own speakers or earphones, I mean, come on man.
  2. No the S means it is compatible with all iPhone 6S and 6S+ with a converter.
  3. Hey that is great, I guess I missed those devices. One question, how accurate are these cheap DMMs with thermocouple type k? My Dynahi reads 55°C at the heatsink wall closest to the output devices (not the fins). Manual says Its resolution is 1°C, and accuracy of 5% rdg + 4 dgt. *Edit: added picture
  4. Been up all night coming up with the proof of concept. Moved the transformer out into a wood tidbits box and hum disappeared completely. Monday I'll go look for a proper project box and connectors+cable for it. Very happy. But my R channel THAT340 is also noisy like some of you. Started to develop around yesterday night. Kinda thinking about the converter boards now but the matched or buying a lot of LSJ/LSK for matching is so expensive.
  5. I only want one set please Steve. Thanks! Wasn't sure if the order was for one only or for a set.
  6. Hi Steve, please amend and put 2 Dynalo for me please! So this is my order. also, do I need to order 2 sets for ubal/bal? 4 GRLV1 Ubal/Bal with PSU (do I need only one or two for stereo?)2 Dynalo
  7. Hi Steve, is it too late to add my orders? 4 GRLV 1 Ubal/Bal with PSU (do I need only one or two for stereo?) 1 Dynalo
  8. Loving this out the balanced as its intended but because my chassis is very cramped the transformer is inducing a lot of hum. Tried removing the boards from the chassis away from the tranny and it was silent as balanced. Looking as how it is, I cannot fit a tranny can over it. Distance between tranny and the boards' reservoir caps are only a few mm apart. I think my next project is to get another PSU board and chassis and house them separately. I guess the transformer is too OP at 160VA. Gain with the gain resistors at 51k is just the sweet spot for me. Volume knob on my DAC pre out is about halfway for my listening volume. Can go very loud real easy with this gain setting. *edit: Does anyone experience sibilance or slight roughness in the treble? I'm comparing it with my Matrix Mini-i headphone out and it sounds a little rougher in the treble region.
  9. Is it this model? If so the center conductor is + and outer conductor is -. You can see the polarity diagram under the label "12V DC ADAPTER".
  10. There's no turn on sound but turning it off does have a soft thud. Don't think I got space in the chassis for a protection board. If I'm to revisit this I'll make a dual chassis build. Or probably get a large one for speaker amps. Unfortunately I got the pass clone chassis with an 8mm thick front panel. I'll figure something out for the volume pot and channel selector. The whole thing is hot but I'm sure it's fine. My thermometer is in the mail, so I'm gonna take note of the temps later.
  11. Dude.... this sounds amazing. Miles away from the Lehmann headphone amp. Should I worry about the initial startup offset? Its peaks to about 400mV maybe, but into my 150 ohm headphones that's like 0.0027 watts. **edit: Goddamn can't listen to binaural tracks now, its 3.27am and I'm alone in the house and its just to creepy to hear all these sounds around me with nobody in sight.
  12. What I did was I turned up the two pots beside the 500R together without looking at the offset properly. So it just kept going up while I was trying to focus counting to match both pots' rotation. To correct the offset I had to turn the other one less or more and that fixed the offset right up. Resistors are different now; 50R are now 100R and 500R now are 680R.
  13. Nope nope guys shit. Sorry I feel so dumb. My biasing technique was wrong. The offset is fine. It goes below 40mV easily and the servo lowers it down to 0mV and maybe fluctuates a bit between 4 to -4mV
  14. There ya go https://drive.google.com/drive/folders/0B_iJFfZStuVhSE5nOHBVdTByR1k?usp=sharing
  15. Thanks a lot for the checklist pars. 1. Yes 2. Didn't verify by meter but their spec is 1.7V. http://my.element14.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=15001&langId=83&urlRequestType=Base&partNumber=2062468&storeId=10188 3. Yes. 4. I didn't verify by meter one by one but their packaging and color bands check out. 1% so won't stray too far.
  16. I'll test that when I have the time. Here's a closeup pic. You can see (just barely) there's an insulator and a washer to insulate MJE devices from the L bracket. For sanity check I've double/triple checked pin orientation with respect to the silkscreen and all components correspond to the silkscreen orientation (had this problem with a NAP200 build where one of the transistors are backwards). I only have 2 units and both boards are exhibiting same behaviour. I tested one of the THAT340 prior to installation, it measures fine and matched within respective P-N channel. So the MJE are rated up to 150V while the MPSW are rated up to 80V. How likely have I fried the devices on my board? Or is it current that fries them and not voltage? There's no smoke, no smell.
  17. V+ and V- look okay, 29.5V and -29.87V. I've checked continuity when I mount the devices to the L bracket heatsinks. Yes there's mica insulators with plastic washers but I cut down the mica heatsinks to size because they're too wide or else they won't stay flat and stack up. That could be the point of failure there. I check continuity on the tab after every 4 devices mounted. I didn't check cross continuity between the devices on the right and left however, I checked continuity on random output device against the heatsink because I assumed if one has continuity then all of them will have continuity. The first 4 devices on the left to the tab of one of the 4 devices on the right side should NOT have any continuity correct? I don't understand you.
  18. Jeeybus, I'm fucked. I can't lower the O+/gnd O-/gnd 3.3V offset at all.
  19. So I am measuring the offset for my balanced build and the O+/O- has near 0mV offset, but the O+/gnd and O-/gnd has 3.3V offset. Is this correct? Won't this destroy single ended headphones since their ground is tied?
  20. The heatsinks are pretty hot with 750mV, plus I'm using a Sigma22 for both boards and their regs are heatsinked to the amp floor panel. The PSU floor is hot too with one board at 750mV so I've lowered it to only 450mV for now. I haven't tried it out yet as my balanced 10k pot it still in the mail. I was wondering will there be any adverse effects if I use my balanced DAC (Matrix Mini-i) as pre out to the dynahi without the 10k pot? Can't really find the output impedance for the Mini-i XLR at the back, but the headphone out is 12 ohms.
  21. Correct, they're red and rated at 1.7V. Replaced them with 360Ω and now can go to 750mV
  22. Oops, I have to echo some of the alternative findings here. The bias goes down instead when I replaced the 500Ω to 680Ω. Got them on sip sockets to change quickly I'm gonna go out and get some lower resistors now.
  23. I'm using a 160VA 2x30V, so that means 160÷2÷30=2.67A?
  24. How much current will the amp pull in total? I want to get a proper rated fuse for it and check whether my Schurter IEC inlet is the proper one. I bought this 2A version way back then without checking first. http://my.element14.com/schurter/3-101-141/iec-inlet-c14-c18-with-filter/dp/2671668
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