dreamie

ablaze, how did u desolder the 5532s? thanks

http://www4.head-fi.org/forums/showthread....&threadid=38123

 

an even longer thread

is there a pic to sumarise everything? Thanks again.!

hehe.. sorry for clone poasting ablaze's thread, but taht threadis seriously getting too long..

can anyone provide me with a link to a webby stating the mods that can be done? Thanks a million.

Mods: Delete this if u dun like it

ok, lets just assume its regulated.

 

my question is, can you tell if its switching or non-switching?

from what it looks..

a transformer and a 7824 regulator? Since a 7824 can limit current up to 1A.

If so then non-switching.

Where to buy these cute little tin cans

tubes... yummy!

Post your porn once you finish... ya...

 

We love to see it...

OK.. i take it that the R2 value wont affect the sound quality adveresly.

sch hols are coming

If you intend to use your tube preamp, I suggest using a polypropylene capacitor for C1. I have no idea what kind of drift is on the output of your preamp. If there is sufficient, you'll have toasted headphones.

nah.. not using it with my tube preamp..

using semiconductor with semiconductor, glass with glass.. currently looking out for the Rozenblit T8 OTL amp schematic.. seems to only be available in Audio Reality..

btw, so R2 (pin 3 to ground at the input signal rail) being changed to 10K is alright?

Thanks for all your input.

You may want to omit the C1 and R5...

i omitted C1 (black gates are just outta my budget ) but used R5. I bought the parts anyway.. might as well use them.

Thx for all your input.

Hmm.. according to this forumla i should be getting a gain of 2, if i followed the original one which used 100k, the gain would be 1.1. 

 

am i correct?

 

Thanks for all your inputs. 

The resistor from Pin 2 to ground is NOT R2!!!

 

R2 is from In(+) pin to ground. ie. Pin 3 to ground on single-opamps!

ops.. 2 wrongs make a right

R2 on this image i meant. Correct?

Thanks for all your inputs too

Heh.. i reckon it got hot because I did them on a project board and they oscillated.

 

Anyway, how would changing R2 (Pin 2 to ground resistor) to 10K from 100K affect the whole circuit?  thanks.

KK...

 

I you use non-inverting amplifier.

 

Gain = Rf/Ri + 1

Rf is the resistor between pin 2 and 6.

Ri is the resistor between Pin 2 and ground.

 

Increasing that resistor will give you louder sound...

Hmm.. according to this forumla i should be getting a gain of 2, if i followed the original one which used 100k, the gain would be 1.1.

am i correct?

Thanks for all your inputs.

Heh.. i reckon it got hot because I did them on a project board and they oscillated.

 

Anyway, how would changing R2 (Pin 2 to ground resistor) to 10K from 100K affect the whole circuit?  thanks.

It's pretty difficult to get the OPA2132/ 2134 series of opamps to oscillate.

Guess you got a short or wrong connection on the opamp somewhere.

If you used dual voltage rails, you MUST connect the virtual ground (or PS ground) to the audio ground.

It's not advisable to change R2 to 10K unless you don't have a pot for volume control.

i Dont have a pot for volume control...

I had OPA134 connect to +-12V but they don't get hot; just warm. Did you short the output to the ground, +V or -V? Really scare me.....

 

To get louder, should try changing higher value resistor between pin 2 and 6.

Heh.. i reckon it got hot because I did them on a project board and they oscillated.

Anyway, how would changing R2 (Pin 2 to ground resistor) to 10K from 100K affect the whole circuit? thanks.

Nope. Seems like a short circuit.

You need to inspect carefully.

 

I burnt one buffer before. $10 one...

btw, i just realised i used 10k as the resistor to ground from pin 3 of OPA134. this wasnt the one i tested though.. this was the one i soldered. .. i think this will result in louder sound..

Hot... Is it still touchable?

I smell of the burnt smell soon after it was switched on. Only touched it after a few minutes of shutting down.

It could be due to oscillations, cause i did it on project board.

As above.

Wanna build a OTL amp but i'm afraid that the impedence, if not matched, will damage the tubes and circuit. What do u guys think?

THe OPA134 on mine got hot.

anyway, i also tried to modify the circuit.

1) Removed input capacitor (save $$.. blackgate too ex. )

2) Output load resistor value is 49.9ohm instead of 50ohm to 100ohm.

3) LED using 150ohm resistor from positive and grounded to 0V (not 10K across +4.5 and -4.5). May need to change the resistor value if i decide to use 2x 9V.

Using the gold stereo jacks (female) u can get from Kaichin. $0.80 each.

Still in development stage. Size is about 1 3/4 of a 9V battery.

Any comments on the modifications? Thx for reading.

love dat foobar...im still on 0.667 cuz its as close to 666 as i can get

you're here

Soundstaging can be explained by the width, heigh and depth of the music presented in front of U. Imagine a stage where the musicians are playing.

ah... thanks..

you didn't read the sticky

http://www.sgheadphones.com/index.php?act=ST&f=2&t=134

cant find soundstage

What does those terms u guys use refer to? like soundstage, cans.. etc..

thx. can be a faq to others too

Analog-devices sample program

cool.. i thot analog dun give samples..

where do u guys get the ad8620 from?

speaking of DIY, anyone knows where i can buy teflon tube or sumthing like that? wanna insulate some cables i'm gonna make..

Farnel carries the ferric chloride granules... can we just buy it? ASK at SLT sells the ferric chloride granule pack (half a KG) at ard $16.50, Silicon Electronics $17 if my memory serves me right.

Yes, you can buy it. They'll ask you for your license though. LOL..

ASK and Silicon at SLT didnt ask for mine