Tubes amp

[Kippei 0]

yep it so differcult to get. once break hard to resource also... the shipping kills it all

[siriuz 0]

i see.. i can't get the 2SK389 and 2SJ109 for the dynalo in singapore either, end up i get from dgardner together with my boards. they cost a (few) bomb(s)! usd10 a pair, and i need 4 pairs for my dynamid

[siriuz 0]

what do you guys think of this: http://cgi.ebay.com/5963-4-NOS-NIB-Vacuum-...1QQcmdZViewItem

[Kippei 0]

No picture hard to see....

 

It seem that GL-5963 is a very old tube. Dated 1950+ from what i dig out of the net. Any other tube without the GL model number is the newer ones. I think we got could have gotten a rare gem. Same with the RCA

Edited January 14, 2006 by Kippei

[siriuz 0]

just hope no one bids higher

[Kippei 0]

Tubes are getting me more excited..

[siriuz 0]

what did you guys use as the CCS for the SOHA? where to get the LND150 arh?

[Kippei 0]

we cant get the LND150 here so we just went with J113 jfets instead

[squalle 0]

yah

 

J113 is good

 

a little better than the LND150

but can get, 50c each at koba

but... they're more fragile compared to LND150

J113 can only take 35v across them. so have to be more careful when u set the cathode resistance down there. dont let it go to 0, then the voltage across the CCS will be too large.

 

oh, using LND150 only needs 2 more resistors. using J113, needs two of them and 1 resistor

 

for millet, well audio not selling 6922?

http://www.wellaudiolab.com/preamp.html

see there. I see there's 6922 there wat

[siriuz 0]

oh ok i think i'll start laying out the psu later. many people seem to have hum issue and most of it seems to stem from trafo placement. so i think i'll have the psu and the amp unit on separate boards and possibly in separate cases

[squalle 0]

hmm for layout, chk a few pages earlier

see my layout there

ideal to be seperated

 

then from PSU, run 4 wires, 60v, +12v, -12v. 0v

 

oh btw, if u want, the +/-12v regulators can be replaced with LM317 and LM337. but have to put 1 resistor and 1 trimpot for each.

however, with that, you can adjust the supply to ur op-amp easily

more flexibility

 

btw, when building SOHA, use the CCS config to be the mu follower. then u dun have headache with those higher input bias current op-amps

can even use the cheaper NE5532

no sound difference. and it's able to output same amount of current as its more expensive OPA2134/OPA2132.

 

I myself planning to build higher power output stage

[siriuz 0]

i have opa2134 left over from my cmoy2 experiments anyway

 

i think i'll stick to +/- 12v regulators, dont really need the extra flexibility

[neutralzz 0]

yah

 

J113 is good

 

a little better than the LND150

but can get, 50c each at koba

but... they're more fragile compared to LND150

J113 can only take 35v across them. so have to be more careful when u set the cathode resistance down there. dont let it go to 0, then the voltage across the CCS will be too large.

 

oh, using LND150 only needs 2 more resistors. using J113, needs two of them and 1 resistor

 

for millet, well audio not selling 6922?

http://www.wellaudiolab.com/preamp.html

see there. I see there's 6922 there wat

millet's not 6922, its 12AE6 or something.

[Kippei 0]

I grounded my pot.. It seem most of the major loud buzz are gone. Now left are those minor buzz and wheeee randomly

[siriuz 0]

@kippei: this guy seems to be selling the tubes for the millett for cheap

 

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