AudioSector-chip amp kits, dacs, chassis

[Peter Daniel]

The 48VA Hammond transformer is ready for dual voltage operation and the board allows switching, by using jumpers.

The board is completely self contained: BNC and RCAs are mounted directly, as well as AC recepticle. The fuse is soldered underneath. Basically you can mount it on a plank of wood (BTW it sounds best this way) and it's ready to use without ned for chassis. That's actually how I'm using it presently, as it does not need additional shielding.

I should be picking the boards middle of next week.

[pinkmouse]

What's the output on those Hammonds?

I would certainly be interested in a kit pack of the difficult to get elements, say, ICs, chokes, connectors, and possibly traffo...

[Peter Daniel]

Initially I was using 2 x 10V AC, but that required removing some of the windings in the receiver section (as the voltage was a bit high for those Panasonic regulators). Later I tried 2 x 8V AC, and it seems to be working fine with both sections (receiver, DAC) without need for modding. So any transformer producing 8V AC should be fine. Please note that there is some voltage drop on series resistors (1V or so)

I was also considering partial kit, with hard to get parts. Some of those parts are simply necessary for best sound and one shouldn't skip them

[Peter Daniel]

I was also experimenting with alternate RCAs and prepared bigger pads so other options are also possible:

[Peter Daniel]

Originally posted by jleaman
Can i email you peter and talk to you ? about the Dac stuff ?

Sure you can.

[pinkmouse]

Originally posted by Peter Daniel
Some of those parts are simply necessary for best sound and one shouldn't skip them

Yes Boss!

The reason I was asking about the traffo is that I have some encapsulated 9-0-0-9 that seem to match the pinout of the Hammonds. Have you estimated current draw for this circuit? My traffos are only 4VA per winding...

[leadbelly]

Originally posted by Peter Daniel
Now the best part. As I mentioned already somwhere else, I'm not that crazy about snubber anymore, and prefer not to use it. I'm getting very good results with AC power and single 100u BG N caps, but with some efficient speakers it may create slight hum of the drivers, or some might prefer more substantial bass signature. So I made extra holes for 1500u Panasonics which can be used together with those 100u caps (preferably BG N) on amp's board. Also, when snubber isn't used, variety of bypass caps are possible to mount in that place, with spacing ranging from 200-400mil.

So Peter, what are you recommending for caps nowadays? Non-BG of course, I'm not there yet If I understand correctly, no snubbers, 1500uF FC's on the PS boards, and 100uF FC's on the main boards?

[Peter Daniel]

In my earlier versions I was using 12VA smaller transformers and they worked fine.

The current draw can be calculated: I have series 20R resistors on both rail and ground feed for each section (4 total ). With DAC the drop is 1.14V and for receiver it is 0.95V

[moe29]

i'd go for the premium kit.

it's worth it to have all those parts with the kit.

maybe a small blurb on how to implement the 2x3 tubing for chasis.
For those of us who are chasis challenged

[jleaman]

Im very excited to get one and get going : O )