Group Build: Dynafet

[DigiPete]

several parts backordered until Mid March-April

[DigiPete]

Several parts still backordered from Mouser.

I will have to bow out of running the group buy for the passive parts,

as I do not have the time to do it justice.

I will gladly share the mouser project file with whoever wants to pick it up.

Sorry,

Pete

[vvs_75]

Guys,

Does somebody already have properly working board? Any chance already finished amp out there?

I understand that everybody have other thing going on, but I would never expected this project die just like that after spending so much money, time and effort on it. Any info. on Dynafet would be greatly appreciated.

Cheers,

Vlad

[luvdunhill]

I have a working board that I offered to send to Team Spain. I plan on picking this project up in a few weeks. I have two things I need to get out of the way and then it will be my number one priority. During that time, I'm more than willing to help people out in any way I can.

[naamanf]

Also in the same boat of wanting to get the ball rolling again. I ended up with SMD version of the board which has some unlabeled pads on the bottom. I think maybe getting some sort of BOM or at least good parts values would be the next step.

[Pars]

I was still planning to build up a pair of the boards I have as drop-in/swap-in replacements for my Dynahi (still uncased ). I could use a BOM as well. Mine are the thru-hole boards.

[hitoridekimasu]

Hi, the Spanish team in currently working on it. Picodeloro is populating two boards and doing the offset and bias adjustments at this moment (but he got sick recently). I'm going to buy the passive parts this weekend and try to start populating the week beginning on the 21st (I'm traveling a lot lately and this is the first week I'm going to stay a bit stable in my home town).

I'm very excited with the resurrection of this thread so that we could deal together with the problems that we could find when trying to make it work as it's supposed. We are going to do a group listening of different biasing options to find out what seems to be better with different cans.

We will keep you informed.

Cheers!

[DigiPete]

I sent my spreadsheet with the complete BOM, as I know it, and my mouser project file to Vlad.

I can share those with anyone else.

[Pars]

I'd take a copy

youngc1 at comcast dot net

Thanks Pete!

[naamanf]

I could also use a copy. Also who has the gerbers for both of the boards (SMD and through-hole)?

[luvdunhill]

I have Gerbers somewhere. But are you really asking for a schematic, or looking for a set of TH boards?

[Pars]

I thought the Eagle files were around somewhere?

[naamanf]

I have Gerbers somewhere. But are you really asking for a schematic, or looking for a set of TH boards?

I guess I could figure out the parts on the bottom by the schematic, but I was hoping either the board files (eagle?) or gerbers had the bottom parts. Just being lazy I guess.

[Pars]

You can run a BOM output (ULP IIRC) in Eagle... not sure how much this would help you as far as where things are (top or bottom).

[DigiPete]

naaman,

send me you email and I'll email you the BOM file I was working on.

Already sent to Pars.

Pete

[vvs_75]

I have a working board that I offered to send to Team Spain. I plan on picking this project up in a few weeks. I have two things I need to get out of the way and then it will be my number one priority. During that time, I'm more than willing to help people out in any way I can.

Hi Mark,

just curious if you have any news for us, winter is the best time for soldering stuff?

?

[Pars]

Bump. Starting to collect parts and re-reading the thread. Hopefully the BOM that digipete sent is accurate, at least WRT part values

[Pars]

I thought the Eagle files were around somewhere?

I have the Eagle files for the thru-hole version but not for the custom SMD version. The files I have are close but probably not the final (don't have the 1x3 pin header for SJ1 for example).

Any recommendations for the feedback setting? I re-read the thread and am leaning towards the standard feedback loop (back to the input FETs), but wanted any experience/advice. Does anything need to change parts wise between the two? I thought I would build this with a stock gain of 11 unless others experience would deviate from this. I assume to change the gain I would increase R56 rather than decreasing R55? I think I will socket R56...

Also, if the alternate feedback loop is used, how is gain set? Does SJ2 need to be jumpered in this case?

Kevin mentions decreasing the 5K resistors to 2K, but I'm uncertain which 5K resistors (R5-R10; R19; R20; R59). I would guess R19-20 is what he is referring to.

[DigiPete]

Bump. Starting to collect parts and re-reading the thread. Hopefully the BOM that digipete sent is accurate, at least WRT part values

All the questions raised above never allowed me to finalize the BOM.

Then I got too busy to work on it further.

Hope someone can finalize the configuration/parts values.

[Pars]

^ I'll try to update as I go along. Marc PM'd me and said he could answer most of these, and would get back to me.

As far as I know, none of the group buy boards have been built, other than it appeared that Jacob built a quad of his. This is probably too low of voltage to attract much attention these days

Edited December 27, 2010 by Pars

[DigiPete]

If someone builds a stable board with around 5-6 gain, that would probably motivate me to build these boards up

and substitute them into my Dynamite.

[vvs_75]

^ I'll try to update as I go along. Marc PM'd me and said he could answer most of these, and would get back to me.

As far as I know, none of the group buy boards have been built, other than it appeared that Jacob built a quad of his. This is probably too low of voltage to attract much attention these days

I think that most off us if not all just waiting for the final BOM. As soon as we have it the amp build will pick up fast. Common guys, bring it on!

[luvdunhill]

ok.

I'll have something posted on 2/1 after I get back and before I leave again. I'll post the values that I used, though for my build. YMMV and all that.

[Pars]

I got some resistors last week (Parts Connexion sale), so am still working (slowly) on mine. I am going to socket the gain resistor (R55?) so I can more esaily play around with it. I do not have all the parts yet BTW, so don't expect any fire in the hole from me for some time... I'm trying to build these up as much as possible with stuff I already have.

Since I am only using half of the output devices, any recommendation as to which positions on the board to use? At least I think I only bought that many FETs from you Marc? You can tell how much looking in my parts stash I have (not) done...

[Pars]

Marc,

Before you leave, could you answer one of questions from post 1247?

Kevin mentions decreasing the 5K resistors to 2K, but I'm uncertain which 5K resistors (R5-R10; R19; R20; R59). I would guess R19-20 is what he is referring to.