Les_Garten
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Posts posted by Les_Garten
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You can use the "Singlepower method", which is to solder a paper clip across the void.
My problem is the opposite. The missing mask exposes the ground plane. I'm trying to seal it up. It's within about 3mm of an output pad on an amp board. Seems my options are to ignore and be careful around it, or try to seal it with something resistant to high temp.
Hmmm, what is the voltage carrying capability and resistance of a paper clip. Can't honestly say that solution hasn't crossed my mind n the past.
I have a call into Loktite to see if they have a high temp epoxy that is reasonably priced.
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finger nail polish, or uber-cryo-milspec conformal coating (conveniently available at Fry's)
There are some Solder mask epoxies, but the price is high. Fingernail polish doesn't seem like it would resist temp very well?
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I just got a PCB that has a void in the solder mask on top of the board. It is not a scratch, the mask is kinda piled up around the void. It looks like a contaminant may have kept the mask off that area. There are some epoxies online to fix this. I was wondering if you guys know of something locally obtainable to fix this?
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It wouldn't hurt to match the 389's but I really wouldn't bother. It should be easy enough to bend the leads on the LSK to the right pattern.
Thanx!
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If I had the heatsinks and could therefore link the singles into a double unit, then I'd use them but I do have a small stash of 389's so I continue to use them instead. The LSK389 is supposed to be better so I might just use that instead when I run out.
How important is it for the 389's to be matched side to side? Is it possible to solder in the LSK389 to fit that footprint?
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Happy to help.
Once people start working on their KGSS amps it might be time to start a thread on them with the correct part numbers, tips etc.I got my Boards this week, very pretty! I sent Dan an email about the 2SK389 subs. If you had the choice of unmatched 2SK389s or matched 2SK170s, you would do the 170s, correct?
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Better yet, just buy them matched. The LSK is not available in the same package as the 2SK389 so you'd have to be creative.
Thanx for that Link, I had read it a long time ago but not caught onto the significance. Answers a question for me though.
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Heh, knob cache. x2.
What amp are you using for your new Canz? Congrats by the way!
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Here's some more, but I'm looking for something like the STAX knobs, maybe a little smaller.
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Pots like these were used on the older Stax amps, SRA-10 and 12 but anything after that used the RK27 version of the same design.
Thought so, if you run across a Knob Cache, turn me on to it. Thanx!
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I just found this one.
Amazon.com: Dual Concentric Knob Black Wide: Musical Instruments
Ugly, but at least I know it exists!
I did a search for Dual Concentric Knob and found it. I'm hoping to find a treasure trove of styles!
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It'd be easier to just fuse the shafts together, wouldn't it?
Hmm, that would be one way to do it. The shafts are 5mm and 8mm. So your average 6mm Vol knob won't work. I suppose you could fuse together and DRILL Baby DRILL! But I would like to find the proper knob.
There's this, but I didn't check to see if it would work:I'm not sure what that knob does but it is 6mm shaft size so it's not meant for these POTs.
I'm thinking that since the POTs exist, the knobs have to also. This looks like the POT that would be on the STAX amps where you have the two channels on that Balance knob.
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Does anybody know where to get knobs for the bottom 2 POTS with the dual concentric turning shafts?
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I used a Beta22+srd-7 pro to drive my O2 Mk1 for about month. It actually sounded a lot better than I thought it would: only slightly dark and less refined. I preferred the O2 Mk1 in this setup to the HD800 so I ended up getting a KGSS and selling my HD800 and Beta22. The KGSS, of course, is a huge improvement.
Good to know I'm going in the right direction! Did you sell your 303s?
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woah, just saw that krmathis is running a beta22 into an srd7-pro and powering 007's
How exactly does that work?
And how does it compare to other SS stax amps? 717, KGSS?
Hi B22 is setup as a speaker amp.
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I think the set I have is the Pomona 5677B, although I could be wrong.
The Pamona and the ProbeMaster. Both of those sets are real nice. Thanx for the info.
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Not sure which leads Fitz uses, but I have most of these and they are versatile and high quality:
Most of the time, I only need one of the weird tips, so I actually bought a smaller set and a single of the less-used tips.
Thanx!
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I don't know about the 179 specifically, but I have a 189 and absolutely love it. Would've probably gotten the 187, since I don't use the logging, but I found a good deal on a used 189 before I could find one on a 187.
One thing I will suggest is getting a decent set of test leads, you wouldn't believe how much they can come in handy. I have ones that'll clip onto component leads so you can easily adjust trimpots and such, tips with a plastic guard that'll safely measure one pin on a DIP IC (like an opamp) without sliding off and shorting against the adjacent ones, ones with long sheathed extensions to measure in tight spots, etc. I really don't know how I got by with just regular test leads before.
I'd probably rather use a more basic meter with good leads than a fancy meter with only standard leads, but maybe I'm just weird.
Hi,
Do you have a link to the Leads you are referring to here? I'm looking and have some leads similar to what you describe, but my leads are pretty cheap and I have no idea what Voltage they are rated for.
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Actually I had never looked close enough to appreciate the holes in the BHSE before. I think if Kevin trys to get holes into his PCB, I'll have to get a bigger desk! Because the board will have to go up 25% in size to accomodate holes!
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just means it'll break in moar faster than you intended, thereby saving you valuable time
Heh, yeah Rapid Charge Break in! Silver lining in every cloud. Thanx for the feedback!
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if it's any consolation, shunted pots sound great
Blown drivers, popped eardrums and severe heart palpitations are nothing compared to that.
Yeah no kidding! But now I wonder about letting that stuff break in unattended for weeks straight like I'm inclined to do. The chance of a failure like that is small, but when that chance nails ya, wheee!
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prepare for maximum volume if the wiper disconnects
Hmmm, I can see that getting Ugly quick! I see what you mean there. I think I had a slight Heart Arrhythmia when I read that...
I'm sensing Rain falling on a parade.
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Hey Thanx! This helped a lot
Interesting reading! Helped explain it a lot more than me just trying to figure out what he's doing here.
Have you seen this method used much?
If this were so good, why isn't it the predominant way of wiring POTs?
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I have a Vol Pot from Audio-GD(Kingwa). They use a different way of wiring their Vol Controllers than I've seen and I wanted to hear what you guys think about the method both advantages and disadvantages. Instead of entering the POT on the input and exiting the Signal on the output after passing thru the POT, he uses the POT as a drain of least resistance it looks to me.
The INPUT from the SOURCE and the OUTPUT to the Amp are on the same solder point. The POT works backwards. As you turn the knob clockwise, the Impedance increases. The Impedance is around 1 ohm when the knob is all the way counter-clockwise.
The way I intepret his design is that the signal hits the solder pad on the POT and makes it's path choice based on least resistance. If the POT is Full CCW, the pad is shorted to ground for practical purposes and the Signal goes to ground. If the knob is turned CW, the impedance goes up and some of the signal starts to flow against the input impedance of the amp and the Vol is increased.
At least this is how I think this works, correct me where needed. He does this with his relay based stepped attenuators as well.
Below is a drawing of the path as well as two PIX of a POT he sent me with the wiring of the board the POT is mounted to. I posted Links to the PIX because they are large.
What do you guys think of this approach?
He says he does this because the POT is not in the signal path so he gets better SQ. The only drawback being on some gear maybe not getting full attenuation of volume when the knob is full CCW.
This idea looks like it has a lot of merit, has it been done by any of you guys or anyone else that you know?
If you recognize the POT, that would be helpful also.
http://www.turbonet.biz/misc/pot/AAA_1934.JPG
http://www.turbonet.biz/misc/pot/AAA_1935.JPG
Thanx!
Repair Solder mask question
in Do It Yourself
Posted
I don't think it needs to be sent back if I can seal it. On the KGSS boards, what is the arc potential at the outputs? It would have to jump 1.40 mm from the R- output Pad. I thought it was about 3mm but it's closer than that. I mic'd it at 1.40mm.