[q2klepto]

Anyone put together a Crack w/ Speedball before?

I got mine used and theres a loud hum - i have to do voltage checks...i wonder if its a dead tube

 

[Armaegis]

I've built three of them.
 
Hum on both sides? low frequency (around 60 or 120Hz) or higher? Check that all the LED's on the speedball boards are lit as well. A defective LED is probably one of the more common blips.

 

[q2klepto]

  I've built three of them.
 
Hum on both sides? low frequency (around 60 or 120Hz) or higher? Check that all the LED's on the speedball boards are lit as well. A defective LED is probably one of the more common blips.

 
It was a ground loop from the RCA jacks - the dude that built it didnt put washers between them and the chassis. Ive done a voltage check and theyre all inline, except for one where i didnt get any reading I'll have to try again tonight. 
 
Now i get a audible noise floor at all volumes, but im thinking its from the tubes themselves. I dont notice it once i play audio past 630 on the pot. 
 
Were yours dead silent?

Ill double check the LEDs though thanks

Heres the thread i posted on the bottlehead forums http://bottlehead.com/smf/index.php?topic=9029.0

 

[Armaegis]

Well a blank reading is usually a broken connection somewhere... or a short that shouldn't be.
 
It's easiest to check the (four?) LEDs by just turning the lights off.
 
The noise floor varies. I've had one that was silent and two that had a low noise floor. It could be the tubes, the twisting of the wires, or how the voodoo plays out. Do you have different tubes to try? I might have a spare input tube to try, but don't have a power one.

 

[q2klepto]

Nope just the stock tubes..not really interested in tube rolling, but for testing purposes ill use em hah
 
The amp works, audio comes out fine - or is it possible for that to happen even if a connection is messed up?

I'll try to verify tonight for that terminal. 

 

[Armaegis]

It's totally possible for sound to come through even if something is off.

 

[q2klepto]

K was able to read that terminal - all good. So i guess the slight noise floor/static is coming from a tube. 
 
I'll have to find a silent tube cuz its kind of irritating lol 

 

[Armaegis]

Do you know which tube it might be?

 

[acidbasement]

Just noticed this Yamaha HP-1 for sale in Winnipeg. If I were still buying headphones I'd be all over this.
http://m.kijiji.ca/pro-audio-recording/winnipeg/yamaha-hp-1-orthodynamic-headphones-1970s/v?adId=1162583182&ck=CK&from=Search&ts=1462933684735

 

[Armaegis]

That guy is asking way too much though. Vintage ortho prices haved tanked due to the million Fostex mods and newer players which have saturated the market. A few years ago you'd get 200 easy, maybe more from the Russians who wanted parts for modding. Nowadays I'd pay 100 for something in pristine condition, but this one is a bit beat up.

 

[acidbasement]

Yeah, I know nothing about current prices,but I really like the HP-2 I got from David/mythless.

 

[q2klepto]

  Do you know which tube it might be?

 
I think it might be the powertube - but over on the BH forums, a dude is saying it might be the braiding from the RCA cables - all 3 are twisted and not braided ..which could pick up emi ..what do you think? http://imgur.com/SiLIf0K

 

[Armaegis]

Yeah, I know nothing about current prices,but I really like the HP-2 I got from David/mythless.

 
I think the only vintage ortho I'd be interested in these days might be a Fostex T10.
 
 

   
I think it might be the powertube - but over on the BH forums, a dude is saying it might be the braiding from the RCA cables - all 3 are twisted and not braided ..which could pick up emi ..what do you think? http://imgur.com/SiLIf0K

 
It the noise more like a ground loop (low hum) or white noise/static?

 

[q2klepto]

right now its more static/low noise floor - funnily last night i was using them and i heard a pop ..and the noise floor went from around 3db to 1db or barely audible..weird

 

[Armaegis]

Strange... I wonder if it was just a sliver of solder or some conductive particle that was toucing something and finally came unlodged.