Jens Rasmussen Leach clone group buy - Page 5 - diyAudio
Go Back   Home > Forums > Commercial Sector > Group Buys

Group Buys Members group buys

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 10th September 2007, 04:59 PM   #41
diyAudio Member
 
soltari_knight's Avatar
 
Join Date: Feb 2006
Location: Michigan
I really like the idea of having a separate output board. It gives us freedom as to the placement/connection of the board and flexibility on the amp's power. However, it goes away from the original intent of simplifying the connections. We also run the risk of improper connection and noise issues.

If we could only find ways to fool-proof the connection, as well as use noise-free, high-current interconnects... But definitely, I agree with tryonziess on using the heaviest copper traces...
  Reply With Quote
Old 10th September 2007, 06:23 PM   #42
hags is offline hags  United States
diyAudio Member
 
Join Date: Nov 2004
Location: Chain o' Lakes
Quote:
Originally posted by tryonziess
i wonder if advanced circuits still has the original information for the last group buy. where are they located. i will give them a call and see if they can do the same deal. the like the thick board idea myself. i will order the heaviest copper, within reason, that they offer. thanks for the input tad

I'm in favor of sticking to the original board layout as seen on http://delta-audio.com/Leach-Clone.htm.

Let's keep it as simple as possible.
  Reply With Quote
Old 10th September 2007, 07:03 PM   #43
gmikol is offline gmikol  United States
diyAudio Member
 
Join Date: Oct 2005
Location: Vancouver, WA
Quote:
Originally posted by BobEllis
IIRC, the last buy was .090 thick, 2 oz. copper. Advanced Circuits got ~$11.50 per at 125 pieces. The price of copper has gone up though.
Quote:
Originally posted by tryonziess
i wonder if advanced circuits still has the original information for the last group buy.
This may be the best bet. I don't know how long ago the last GB was, but if they've still got the tooling, that could cut the cost a little bit. Only issue is if they'll let Tad re-use the tooling since it technically belongs to Bob's account.

--Greg
  Reply With Quote
Old 10th September 2007, 07:33 PM   #44
diyAudio Member
 
BobEllis's Avatar
 
Join Date: Sep 2003
Location: Upstate NY
It wasn't me - gengis ran the buy. The search engine says he was online 3 weeks ago, but he hasn't posted in almost a year. The problem with using his tooling is that it was for the 6 output version, not the one we want.

The boards were 2 oz copper for $11 at 200 pieces. So $12 for 50ish is pretty good if the quality is there. AC boards are great quality.

Tad, don't forget to add in the cost of tooling, shipping to you and packing materials when you figure out the selling price. Voice of experience.
  Reply With Quote
Old 10th September 2007, 07:39 PM   #45
diyAudio Member
 
Join Date: Nov 2005
Location: Ohio
Do you guys just do a P2P PSU? Or are there some PSU boards you could use for these?
  Reply With Quote
Old 11th September 2007, 05:30 AM   #46
diyAudio Member
 
Join Date: Feb 2007
Location: Gulf Breeze, Florida
You can put me down for 2 sets. Thanks!
  Reply With Quote
Old 11th September 2007, 07:13 AM   #47
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
if the voltage amp board and the output board are separated, then only the output board needs the thicker copper. This could save significant money if the GB is large enough to actually order two separate PCBs.
The simple connection between the two boards is 0.1inch pitch PCB holes. That leads to many choices for the permanent or pluggable connection.

The original Jens' PCB demanded a very large area heatsink due to the layout. That can be made more compact.
Separating the PCBs can go further in allowing a smaller area heatsink. The 3pair or 6pair option does seem attractive.
What if the driver pair were kept with the 3pair output? Then twin drivers could be used for the 6pair arrangement.
A secondary advantage in separating the PCBs is removing the high current connections, which have a very high loop area in the Jens' layout, from the voltage amp stage. It will still allow the choice of a common voltage feed to all stages or separate voltages to the stages.
Take the time to rethink, gather some views and decide if changes are advisable.
__________________
regards Andrew T.
  Reply With Quote
Old 11th September 2007, 08:02 AM   #48
pool is offline pool  Sweden
diyAudio Member
 
Join Date: Oct 2004
Send a message via ICQ to pool
Im in for 4 boards with 10 outputs . I added myself to the wiki..
  Reply With Quote
Old 11th September 2007, 10:10 AM   #49
diyAudio Member
 
Join Date: Apr 2007
Default Andrew

If we provide a separate power supply to the input stage, ie 10 transistor version, what would it look like. Could you show us a sketch of how you would make the two separate supplies. How much power would be necessary to just run the input stage. On Jens website he has what i consider to be a rather large voltage drop from no load to full output. With the separate stage their would be less or non at all impact on the driver stage. I like this arrangement. Putting these amps together is not going to be cheap. I would like it to be done with the final results being close to perfect. That would be nice. Thanks Tad
  Reply With Quote
Old 11th September 2007, 11:34 AM   #50
hags is offline hags  United States
diyAudio Member
 
Join Date: Nov 2004
Location: Chain o' Lakes
Default Re: Andrew

Quote:
Originally posted by tryonziess
If we provide a separate power supply to the input stage, ie 10 transistor version, what would it look like. Could you show us a sketch of how you would make the two separate supplies. How much power would be necessary to just run the input stage. On Jens website he has what i consider to be a rather large voltage drop from no load to full output. With the separate stage their would be less or non at all impact on the driver stage. I like this arrangement. Putting these amps together is not going to be cheap. I would like it to be done with the final results being close to perfect. That would be nice. Thanks Tad

I'm in for at least four 10 transistor version boards as shown on http://delta-audio.com/Leach-Clone.htm.
Count me out if there is any deviation from the original.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
WTB:2 boards from Jens Rasmussen Leach clone group buy mpmarino Swap Meet 0 12th January 2009 11:53 AM


New To Site? Need Help?

All times are GMT. The time now is 01:02 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2