[looser101]

Some pics for TomB

And before anyone asks... no, I am not using any LEDs.

Thanks go to tomb, dsavitsk, n_maher, and of course pmillet.

 

[tomb]

It's tough to capture those UV Leds in a photo, but they sure do look nice in person.

The natural orange glow is very nice, too!

Nice job, guys! Great pics, too!!

 

[tomb]

Quote:

Originally Posted by Fitz /img/forum/go_quote.gif I heard MacGuyver did it with only some pocket lint and an apple.

One day, Pete Millett will make us an amplifier design out of pocket lint and an apple, too. Dsavitsk will improve on it by adding a high-tech shirt-button mod.

 

[Juaquin]

Those UV LEDs look wicked - contemplating taking my amp apart to make the switch, but better not to fix something that isn't broken, knowing my luck.

 

[PJPro]

Quote:

Originally Posted by PJPro /img/forum/go_quote.gif Well, I've added most of the components to the PCB and am unable to progress as I haven't completed the tube socket mods. I managed to remove the centre pin without drama (using my pillar drill) and now need to glue to the two halves together. Anyone care to recommend a brand/type of epoxy available in England?

I've gone for Araldite. It should be OK. It can cope with heat up to 60degC.

 

[Tritonpad]

Hi there,

sorry if the question has already been asked, but I am wondering what values i should use for R16/R17 considering my headset is a AKG K701 ??
(I'm talking about the pcb kit... so that would be 50k or 100k ?)
I know K701 is 62ohm, but I'm quite new in DIY and it's hard to take a decision...

Thank you in advance ^^

 

[tomb]

Quote:

Originally Posted by Tritonpad /img/forum/go_quote.gif Hi there, sorry if the question has already been asked, but I am wondering what values i should use for R16/R17 considering my headset is a AKG K701 ?? (I'm talking about the pcb kit... so that would be 50k or 100k ?) I know K701 is 62ohm, but I'm quite new in DIY and it's hard to take a decision... Thank you in advance ^^

The K701's are not very efficient - at all. I'd use the 50K or even jumpers, perhaps.

 

[Tritonpad]

Ok thank you... That's what I was thinking. I 'll try with 50k first just to see... then I'll go to jumpers if needed...

 

[sandbasser]

I've noticed a very audible hum in the earphones (Grado SR80 or Denon AH-D950) at low volume levels. The hum goes away completely if I touch the tubes, case or standoff screw. The hum is equally bad with an battery player (Sansa Cube or Fuse) or a powered player (my computer).

I'm suspecting some kind of ground fault. Any suggestions would be greatly appreciated.

OTOH - it's a little bit cool in a kinda Theremin like way... the hum goes up / down in volume when I pass my hand near the case. Very strange.

One more query... will the hum actually damage anything in the amp, phones or player???

Edit: I tried 2 different power adapters - no difference. Right now, I only have one RCA cable - i'm going to try to fab one this weekend, although I doubt it will make a difference.

Thanks,

 

[thelast]

I'm having the same issue as "sandbasser". I hear a hum when using low impedance earphones but when I use my dt880(250 ohm) i don't hear it anymore.

If I put my hand over the tubes and touch the rca's the hum goes away completely. Grounding issue maybe? I don't know. Any help would be appreciated.

 

[tomb]

OK, here's some questions for you guys:

1. Did you build the SSMH PCB?
2. If you built the SSMH PCB, did you use the Hammond case?
3. Did you scrape the anodizing completely off around the RCA jack holes and around the center standoff on the case lid?

The power supply is isolated as best we can tell (switching supply, multiple mfrs, variances, etc.). I've built four of them so far and the only one that's had a hum is the one that I left uncased. Even in that one, if I touched the RCA jacks, the hum went away (which implies a grounding issue).

If you are careful to make all the grounding contact mentioned above, you should not have a problem. I've never had a hum in any of the others with a wide variety of sources. So, if you get hum but are able to answer YES to those 3 questions, I'd have to suspect either a bad power supply, bad tubes, or both.

 

[thelast]

Tomb, in regards to your questions

1. Yes, I built the amp using the kit with the custom hammond case
2. Yes
3. I just finished disassembling the case and made sure I scraped the anodizing completely.

But now I have another problem. I assembled the case and now the amp won't turn on. I'm guessing it's the power supply since it was working fine before.

 

[the_equalizer]

Quote:

Originally Posted by MoxMonkey /img/forum/go_quote.gif ... also i've never seen anything nearly as well packed as my recent beezar order

x2

Outstanding packing from TomB, simply outstanding

Cheers!

 

[TeraHz]

Hi, I've been listening to the SSH for a week now and I believe the low freqs. are distorted. My signal follows this path: FLAC -> y2 -> SSH -> Grado SR80.

There are not EQs in software. Is anyone experiencing similar results?

 

[tomb]

Quote:

Originally Posted by thelast /img/forum/go_quote.gif Tomb, in regards to your questions 1. Yes, I built the amp using the kit with the custom hammond case 2. Yes 3. I just finished disassembling the case and made sure I scraped the anodizing completely. But now I have another problem. I assembled the case and now the amp won't turn on. I'm guessing it's the power supply since it was working fine before.

Check that center standoff for a short on the LED resistor trace. The power supply has an automatic cutoff in case of a short. If you can measure 48VDC from the power supply connector when it's not connected, then you've got a short that developed when you re-assembled the case.