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Jens Rasmussen Leach clone group buy

I emailed Jens the other night to see if he had any objections to a group buy of his leach design. It was o.k. with him. Now would there be any interest out there for this project. There are several versions, ie, the 10 transistor and 6 transistor version. I am currently waiting delivery of my AAK symasym boards to build. I would like a project waiting when i finish them. Let me know of any interest in the Leach clone project. The board i am talking about can be seen at www.deltaaudio.com
 
You must have read my mind, I was about to email Jens myself! I would be interested in a few pair of boards, depending on the price point. Does anyone know of a good PCB house? I'll ask around at work to see if any of the board designers know of good/cheap places. I'll also try to get up with BrianGT since he is well versed in this now.

Regards,
David
 
reply to jens leach clone

I think there is a place in Atlanta that does boards fairly reasonable. If we can get a large board order the per unit price will drop significantly. I was planning on bridging two boards for 300+ watts. The parts would be cheaper than 200volt parts for the super leach. If Jens decides to do a group buy on the Super Leach i would of course buy some of them also. What are you wanting the 6 or 10 unit version. Tad
 
Tad,

I was interested in a 6 transistor version, but will go with the flow of interest.

Are you thinking of PhotoCircuits in Peachtree City? My dad used to work for them, I'll give them a shot at a quote. I've already sent emails off to Flextron Systems, who a co-worker has recommended, and BrianGT, for advice on where to get a good value for boards.

Below are the specs I included in my Request For Quote, this is for the 6 transistor version, but I would be ok with which ever one generates the most interest. The specifics about board color thickness, and plating options are also not fixed, but these are generic values. Feel free to use this list when asking for quotes.

______________________________________________________
Material Type: FR-4

Finished Copper Thickness: 2 oz

Board Thickness: .062”

Board Dimensions: 4”x9”

Solder Mask: Both Sides

Color: Black

Silkscreen: Component Side

Minimum Line Width: 12 mil

Minimum Line Spacing: 12 mil

Number of Drill Sizes: 11

Number of Holes: 691

Smallest Hole: .6mm

Surface Mount Pads: Yes

Number of SMD Pads- Comp. side: 8

Number of SMD Pads- Solder side: 0

Finest Pitch SMD: 0603

Array: No

X-outs allowed: yes

Electrical Test: No

Plating: Copper

UL Approved: No


Quantity:

Please quote price break points up to 100 boards.


Lead Time:

Very flexible, approximately 6-8 weeks.

______________________________________________________


The next step would be to see how much interest this generates. A wiki would be nice to keep tabs on quantities. I'll work on one unless someone else who has done one before wants to knock one out quickly.

We need to at least specify the number of boards wanted, the number of transistors wanted (6 or 10), the color of the board, and whether or not gold plating is desired.

Regards,
David
 
I know you just said you weren't soliciting suggestions for layout improvements yet, but...

How about make the boards so that the output stage could be separated from the front end - like that shown in the superamp redesign thread. IIRC, it wouldn't take too much rework to make the needed connections fit a SIL connector.

If you were to make a 5 output pair board and provide a separation point between the first three pairs and the last two, we could just snap off the unused portion if we want to make a smaller version. Even better in my book would be to make it a 6 pair board, so we could go 3 and 3 if desired.
 
Bob, I am not to adept at drawing pcb schematics. The files for Jens board are readily available to us and I was planning on using his design. Separating the input from the output has many advantages i just do not have the program to draw it. The size of the current board Jens has drawn i believe is outside the current limits of Eagle lite.
At present i am researching the availablity of a low priced cnc router to use for small quantities of pcb's like this project. I would very much like to have the capability to mill out board projects for some of the ideas on this forum. Regards Tad Ellis
 
Leach amp board

TAD

Pending final costs, please cont me in for at least 10 boards (10 transistor version prefered).

Although some of the requested changes for the board design seem interesting, I would rather have boards that are exactly like the original board by Jens Rasmussen.

Thanks for your effort.

LS