Most likely it is already known, but Pete Millett has a suspension adapter for the Nutube. I have used one and found it to be incredibly useful and effective. In light of that, I bought two more to use on other Nutube units that I have made.
FWIW, I agree with the above post about the Nutube being a good match for a class D amp. It just so happens that I built Pete Millett's 50WPC amp which uses the SP1 tube in the input. It was a headshaker. Some of the engineers out there are really incredible with using new technology with old and beating the game.
FWIW, I agree with the above post about the Nutube being a good match for a class D amp. It just so happens that I built Pete Millett's 50WPC amp which uses the SP1 tube in the input. It was a headshaker. Some of the engineers out there are really incredible with using new technology with old and beating the game.
That's the one alright. I do think that there are other ideas that lead to this tube performing at it's best in tandem with the suspension product that Pete Millett has offered. FWIW, I bought 2 of the last 3 available at this time so there's only one left in stock. One idea in particular is to not use the bolts and spacers given in the kit and instead use soft silicone rubber board mounts. With mine, I even use small O rings to lift the board above the bottom plate so that there isn't something awful that happens when the bottom of the circuit board bottoms out on the metal bottom plate of the enclosure.
Thanks Soundhappy for the sharing! Indeed M.Pass work are a lot less trouble to build thanks to the diyaudio staff. What I like with Kaneta san is that he test his creation with High effiency drivers and Denon DL 103, a setup ressembling mine. Indeed interesting design !All Kaneta audio gear is always build point-to-point on the perfboards
Athletic training with soldering iron
Papa style DIY is super easy !
You can find pdf. documentations on this blog: レポート | 趣味の自作半導体アンプ
Nutube Current Power IVC MK2 http://myaudio.sakura.ne.jp/report/6P1_Current_Power_IVC_MK2_電圧伝送対応.pdf
Nutube Current Power IVC http://myaudio.sakura.ne.jp/report/6P1_Current_Power_IVC_電圧伝送対応.pdf
Power Supply Box2 http://myaudio.sakura.ne.jp/report/ACPowerSupplyBOX2.pdf
Korg Triode USB DAC http://myaudio.sakura.ne.jp/report/I2S接続USB DAC作成レポート.pdf
No Problem with NuTube sounds great. Still on my original head gasket on my Elise too. No problem a PRRT won't prevent - small world.
The biggest effect on this tube, in my experience, is vibrations through the mounting pins. So whether one uses PM’s suspension product, or how the builder in post #6048 did it, or my less elegant approaches (pictured below along with the board I used purchase from Ebay & double-sided sticky foam from Home Depot) all will help stop vibrations to the tube. One is straight wire attached to the Ebay board the other is a looped wire soldered directly onto the Nutube pins (all wire is the multi-stranded flexible silicon coated type and tubes are mounted on foam). This is probably the best bang-for-the-buck to eliminate most ringing/microphonics with the Korg. Yes, sound damping will also be a productive endeavor as well.
Electronic failings of the tube is a completely different story.
Cheers, Pete
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Just to put things in perspective. And maybe I'm very lucky. But I have no ringing at all. I used only double sided tape for dampening. The board is mounted inside the class D power amp. The housing has slids. Definitely not all NuTubes behave the same.
Yes, I think that both of you are correct in that 1) each tube seems to be of it's own goodness or shortcomings, 2) the damping supplied with the tube may be just fine, i.e. I have experienced both of these situations. One tube is without ringing the next is unusable in comparison, and some even ring all by themselves!
When I built the 50w class D amp that PM offered, the tubes rang excessively, then stopped. I did nothing different. After that, the amp sounded so incredible that it was a headshaking experience. I have built many Nutube products and overall am enamored with their sound.
When I built the 50w class D amp that PM offered, the tubes rang excessively, then stopped. I did nothing different. After that, the amp sounded so incredible that it was a headshaking experience. I have built many Nutube products and overall am enamored with their sound.
I am so glad you like it.
Power supply CLC filtering is costly, but inductive wirewound 5 Watts power resistors
10R and 270R are cheap and upgrade sound
Enjoy
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Still getting hiss
Absolutely loving this build, but I still get a hiss that isn't terrible but is keeping it on the bench in favor of a DCB1.
Does not seem effected by volume. Good continuity between ground and chassis. Nutube rings when you touch the chassis, but in normal playing I don't notice it.
Currently have just the eraser on top, had foam underneath but I took that out.
Any suggestions?
Edit- took out the filter to make sure that wasn't it.
Absolutely loving this build, but I still get a hiss that isn't terrible but is keeping it on the bench in favor of a DCB1.
Does not seem effected by volume. Good continuity between ground and chassis. Nutube rings when you touch the chassis, but in normal playing I don't notice it.
Currently have just the eraser on top, had foam underneath but I took that out.
Any suggestions?
Edit- took out the filter to make sure that wasn't it.
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If the ALPs pot, or the L-bracket it’s mounted on are not grounded to the chassis just try that. Your aluminum bracket looks like it’s glued to the chassis? I’m supposing your PCB is mounted to the chassis with conductive standoffs?
Pete
Pete
Yes I followed the build guide section 4 - "use an aluminum L-bracket, a small wooden block, and a hot glue gun to secure the volume pot." In my defense I was trying to bring the pot further in as the shaft was way too long for the knob I had...
Good news, while I was testing the grounding on the pot/bracket I noticed one of the signal wires was just touching the metal frame of the pot. I moved it up and it seems much better.
Will also look into passively attenuating, thanks NP I do have more gain than I need in my system so there might be an additional benefit to that.
Good news, while I was testing the grounding on the pot/bracket I noticed one of the signal wires was just touching the metal frame of the pot. I moved it up and it seems much better.
Will also look into passively attenuating, thanks NP
I do have more gain than I need in my system so there might be an additional benefit to that.