[dsavitsk]

Form factor is the same. Basically we switched to a new and much nicer power transformer. This required altering the power supply a bit and moving some components around, but we were careful to keep the tubes and all panel components in the same spots, so the case won't change. We are hopeful that this fixes the hum issue -- though, I should reiterate that the hum issue is really less of an issue than I think people believe.

 

[tomb]

 
Quote:

a new and much nicer power transformer

= toroid.

 

[jdkJake]

I should reiterate that the hum issue is really less of an issue than I think people believe.

I agree that is true for low impedance cans using the low impedance tap, especially grado's. Using high impedance cans on the high impedance tap, like an HD650, makes the issue more pronounced. At least on my build.

Looking forward to seeing the changes.

 

[J-Pak]

Any updates? Thanks

 

[soundlikes]

I demand updates ... summer is here and I need a new project !!!!!!!!!!!! 

 

[jdkJake]

The natives are restless... 
 
And rightly so. The current version, with the lid off, is THE go-to Grado amp for me.
 
Something about it and the HF-2's. The amp just disappears and the music comes to the forefront, as should be. An almost organic quality to the pairing. A most excellent combination. That much is for sure. 
 
Makes you wonder how far a parafeed design can take you....

 

[tomb]

The new transformer is in hand, along with the PCB's.  I have the parts on order.  So, it should only take a weekend when I'm free to have some results.

 

[tubey1]

Quote:

Form factor is the same. Basically we switched to a new and much nicer power transformer. This required altering the power supply a bit and moving some components around,

 
Quote:

The new transformer is in hand, along with the PCB's. 

Does the BOM currently appearing on DIYforums.org and the current PCB on beezar reflect the changes to power supply and power transformer Doug is talking about? I just wanted to make sure before I submit an order with Mouser.

 

[dsavitsk]

No, not yet. Tom has been super busy lately, so we are still in a holding pattern. We'll update this thread as soon as we have tested and approved the changes.

To be more specific, the version with the toroid, assuming all goes well, will lose the choke, and the PS cap complement will change a little.

 

[tomb]

I am building it this weekend, hell or high water!!
 
Yes, we have both been busy.

 

[tomb]

OK - I got almost everything done except the big stuff, and I'm only waiting on C3.  Mouser backordered it on me but I never noticed because I was concerned about the NJM regulator.  I got that from Dsavitsk, but I have a different C3 on order and it's already shipped.  So, it should only be a couple of more days ...
 
EDIT: C3 is a 50uf 400V cap on the V2 PCB.

 

[jdkJake]

Pics TomB, pics!

The masses, including myself, are starving!

 

[tomb]

Quote:

Pics TomB, pics!
The masses, including myself, are starving!

I am only waiting on C3, the coupling caps (both in transit), and installing the transformer.  I'm saving the transformer for last, because I didn't want that shotput flexing the board while I still have parts to install.

 

[HiGHFLYiN9]

I really enjoyed building my first one, it's easily the best amp I've heard in it's price range. Dsavitsk, would a balanced drive option be worthwhile running two of these new boards in parallel... or would it be an act of pointlessness?

 

[tomb]

I can't answer the specific question you've posed to Dsavitsk, but you may enjoy seeing these:


 
EDIT: Fixed 2nd pic link ...