Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › The Christiansen "DG" 300B Amplifier Build Thread
New Posts  All Forums:Forum Nav:

The Christiansen "DG" 300B Amplifier Build Thread - Page 29

post #421 of 631

It looks great.  The knob is definitely better.

post #422 of 631
Thread Starter 

Thanks.

It's an entirely different look.

I put a coat of lacquer on it last night and the grain popped.  It matches the sides now.  I am very happy.

 

EDIT:  I really like the attenuator.  The step clicks are very smooth and the sound is great.


Edited by sceleratus - 8/23/13 at 8:38am
post #423 of 631

That's great.  I was just wondering about the attenuator.  To be honest, I cannot hear differences in pots, or perhaps it's just that I don't know what to listen for.

post #424 of 631
Thread Starter 

I'm not sure I can tell the difference either.  They are very close.  I'm just pleased that it sounds good; very clean.  I also like the tactile clicks. I was worried about that but I think I like it better than a pot.

post #425 of 631

That's a sweet looking amp. Nice execution. Thanks for sharing your experience.

 

~Tom

post #426 of 631
Thread Starter 

Beauty shot with finished knob...

 

 

post #427 of 631
Quote:
Originally Posted by tomchr View Post

That's a sweet looking amp. Nice execution. Thanks for sharing your experience.

 

~Tom

 

How much power is this estimated at,  could it handle 5W the HE-6's ?

post #428 of 631
Thread Starter 
Quote:
Originally Posted by catfish View Post

 

How much power is this estimated at,  could it handle 5W the HE-6's ?

This is the OPT specs from Jack Elliano at Electra-Print

 

 

post #429 of 631
Quote:
Originally Posted by catfish View Post
How much power is this estimated at,  could it handle 5W the HE-6's ?

 

The DG 300B Amp delivers 10 W into an 8 ohm load (1 % THD). Clipping (3 % THD) happens at about 12 W. 

 

~Tom

post #430 of 631
Quote:
Originally Posted by tomchr View Post

 

The DG 300B Amp delivers 10 W into an 8 ohm load (1 % THD). Clipping (3 % THD) happens at about 12 W. 

 

~Tom

 

This is fantastic.  My only concerns are sceleratus's comments that there is some noise.  What makes a great headphone amp is a simple test.

 

Play music on your most sensitive/efficient headphones about as loud as you like.

 

Then play a "silence" tack which is basically just digital null.   If you hear any noise it affects the SQ.  Its a better test of a headphone amp than any THD,IMD, FFT, etc.

 

I suspect this amp would pass the test with flying colors for orthos but may not for Grados and Senns,  which is fine really we all need more than one amp wink_face.gif

 

I want to build something similar,  I really like the Madia regulator as I think it is a great step toward a black background SET.  But I am a little apprehiensive about the smps DHT heat.?

post #431 of 631
Quote:
Originally Posted by catfish View Post
This is fantastic.  My only concerns are sceleratus's comments that there is some noise.  What makes a great headphone amp is a simple test.

 

I suspect this amp would pass the test with flying colors for orthos but may not for Grados and Senns,  which is fine really we all need more than one amp wink_face.gif

 

I want to build something similar,  I really like the Madia regulator as I think it is a great step toward a black background SET.  But I am a little apprehiensive about the smps DHT heat.?

 

I seem to recall that Sceleratus reported that using differential inputs took care of the noise. It's possible there was a ground loop in his first setup...

Regardless, I have some experiments underway for using output transformers with higher turns ratio for driving headphones. This should dramatically reduce any noise. I'll be testing this with my Sennheiser HD650.

 

I understand that some people fear switchers. I'm not really sure why. I compared a linear lab supply versus a switching supply for the 300B filament supply in an earlier 300B design of mine. You can see the results here: 300B Switchmode Filament Supply. I am not able to measure any significant difference between a linear supply and my switchmode supply. But the switchers are so much easier on cost and on the thermal budget.

 

~Tom

post #432 of 631
Quote:

Originally Posted by tomchr View Post

 

I understand that some people fear switchers. I'm not really sure why.

 

Audiophile BS, that's why.

post #433 of 631

That is my suspicion as well. But as my measurements show (see link above), the fear is rather irrational.

 

~Tom

post #434 of 631
So does DG stand for dubstep girl? biggrin.gif
post #435 of 631
Thread Starter 
Quote:
Originally Posted by Dubstep Girl View Post

So does DG stand for dubstep girl? biggrin.gif

Well I guess it could.

Right now it's "Damn Good"

New Posts  All Forums:Forum Nav:
  Return Home
Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › The Christiansen "DG" 300B Amplifier Build Thread