Commercial Gainclone kit- building instructions - Page 3 - diyAudio
Go Back   Home > Forums > Commercial Sector > Vendor Forums > Audio Sector

Audio Sector Kits & PC boards from AudioSector

Reply
 
Thread Tools Search this Thread
Old 13th May 2008, 08:22 PM   #21
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Default Re: which transformer?

Quote:
Originally posted by gychang
I will be following this thread, but I get confused on the transformer to get about 55W/ch in stereo from GC.

Anyone know the website for the appropriate transformer?, need cost-effective solution for the classic GC kit from Peter.

Any of the model here work?
http://www.apexjr.com/miscellaneous.html#Toroids

or here:
http://www.partsexpress.com/webpage....e_ID=3&x=0&y=0

do I need one or 2 transformers. (please say 1 )

gychang
Partsexpress is more suitable choice. Go with a single Avel 250VA transformer, either 2 x 25V for 8 ohm speakers, or 2 x 18V for 4 ohm speakers.

I will post tomorrow more info how to wire single transformer.
__________________
www.audiosector.com
Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it. - JC
  Reply With Quote
Old 13th May 2008, 08:42 PM   #22
Colin is offline Colin  United Kingdom
diyAudio Member
 
Join Date: Aug 2003
Location: UK
For UK Gaincloners, this Airlink transformer is a good substitute for the 300VA Piltron. Kensai (I believe) recommended Airlink on another thread. I received my Airlink toroid earlier this week and it seems a very solid unit. One offs are about 32 including delivery.
  Reply With Quote
Old 13th May 2008, 09:08 PM   #23
gychang is offline gychang  United States
diyAudio Member
 
Join Date: Feb 2005
Location: Davis, California
Default Re: Re: which transformer?

Quote:
Originally posted by Peter Daniel


Partsexpress is more suitable choice. Go with a single Avel 250VA transformer, either 2 x 25V for 8 ohm speakers, or 2 x 18V for 4 ohm speakers.

I will post tomorrow more info how to wire single transformer.
My speakers are 8Ohms.

Is this the right one, I only need one right?
http://www.partsexpress.com/pe/showd...number=122-625

I will be looking forward to your instructions.

gychang
  Reply With Quote
Old 13th May 2008, 09:15 PM   #24
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Yes, Avel Y236652 250VA 25V+25V Toroidal Transformer is right choice for 8ohm speakers.

If you don't mind spending a bit more, Avel Y236750 330VA 25V+25V is a good choice too.
__________________
www.audiosector.com
Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it. - JC
  Reply With Quote
Old 15th May 2008, 01:39 AM   #25
Bluto is offline Bluto  United States
diyAudio Member
 
Join Date: Sep 2007
Location: WI.- near the Dells
Hi Peter -

My boards just arrived about an hour ago. The quality is very impressive. Thank You again.

How many questions do you want here on list vs. via PM?

I already have several 'dumb newbee' ones myself.

Bluto
  Reply With Quote
Old 15th May 2008, 01:46 AM   #26
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
No problem with all the questions in here.
__________________
www.audiosector.com
Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it. - JC
  Reply With Quote
Old 15th May 2008, 03:30 PM   #27
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Quote:
Originally posted by Peter Daniel
This concludes the assembly and we have two separate amp channels with separate bridge rectifiers. All is needed now is to connect 2 transformers (one per channel) as per schematic posted here: http://www.diyaudio.com/forums/attac...amp=1210694958 , connect the input (SG for ground, IN for signal input) and output ( OUT to positive binding post, OG to negative) and we have a working dual mono amplifier.
And this is how one complete amp channel looks when wiring is done. The transformer primaries are not connected yet, and I will explain it at later stages.

I usually use 26ga solid core wire for input signal and I never found a need for shielded cable. I normally don't even twist them, but it's a good idea anyway.

For speaker connections I use 19ga stranded wire.

See this table for American Wire Gauge Table:

http://cc.msnscache.com/cache.aspx?q...b17&FORM=CVRE2
Attached Images
File Type: jpg wire1.jpg (86.5 KB, 12649 views)
__________________
www.audiosector.com
Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it. - JC
  Reply With Quote
Old 15th May 2008, 03:33 PM   #28
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Those are some tools you may find useful for wire insulation stripping:
Attached Images
File Type: jpg strip.jpg (81.2 KB, 10527 views)
__________________
www.audiosector.com
Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it. - JC
  Reply With Quote
Old 15th May 2008, 05:55 PM   #29
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
By stereo version I mean the use of a single transformer powering both channels. You could still use two separate rectifiers boards, but depending on wiring it may produce hum in some systems, so I always stick with a single rectifier board when using one transformer.

For demonstration purpose, I will install all the boards inside 3 x 1.5" U-channel, 1.25" aluminum extrusion. For normal listening, this is enough to dissipate heat from the chips, and when things get hot, you can always attach it to larger aluminum panel.

I will show a version with a potentiometer, and without, so stay tuned.
Attached Images
File Type: jpg stereo1.jpg (81.6 KB, 12210 views)
__________________
www.audiosector.com
Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it. - JC
  Reply With Quote
Old 20th May 2008, 02:45 AM   #30
diyAudio Member
 
Join Date: Oct 2006
Default bump!!!

Hello Peter,

Great thread.

My buddy just ordered 2 3875 classic kits last week. I will be the builder. One kit for my studio monitors and one kit for his home stereo.

Can't wait for the rest.

I will be building 2 stereo versions.

I also had a question about internal wiring of the inputs/outputs and passive pot.

I use mogami 2549 mic cable it is OFC 22 gauge shielded.

DC Resistance
Inner Cond. 0.058W/m(0.018W/Ft)
Shield 0.013Ohms/m(0.004Ohms/Ft )

Capacitance at 1kHz, 20C
K0 76pF/m(23pF/Ft)
K1 11pF/m(3.4pF/Ft)

I use this for all my interconnects and mic cable in my studio.

Would this be ok/good to use for the input and output (and pot) wiring?

Out,

Robert

p.s. you have amazing machining skills.
  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
Commercial complete Gainclone kit for a beginner? gychang Chip Amps 365 4th October 2011 09:19 AM


New To Site? Need Help?

All times are GMT. The time now is 06:55 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