Avondale NCC200 module pics - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 13th August 2003, 08:49 AM   #1
diyAudio Member
 
Join Date: Apr 2003
Location: Cambridge, UK
Default Avondale NCC200 module pics

For your general enlightenment, here's some pics of my latest project, based around Avondale Audio's NCC200 modules - see http://www.users.zetnet.co.uk/avondale/

Cheers
IH
Attached Images
File Type: jpg front-1-x.jpg (76.1 KB, 2554 views)
  Reply With Quote
Old 13th August 2003, 08:55 AM   #2
diyAudio Member
 
Join Date: Apr 2003
Location: Cambridge, UK
Here's the innards -

PSU is a 35-0-35, 625VA transformer and 2 x 22000uF caps. Rectifier was built on another Avondale PCB using (IIRC) BYW51 fast-recovery diodes.

The internal power wiring is mostly Silver Anniversary bi-wire (as it's basically very chunky ribbon cable), and as you can see I've tried to avoid supply & return currents from forming any loops of substantial area.
Attached Images
File Type: jpg x-topview.jpg (91.9 KB, 2517 views)
  Reply With Quote
Old 13th August 2003, 08:58 AM   #3
diyAudio Member
 
Join Date: Apr 2003
Location: Cambridge, UK
Here's a closeup of the module itself. I bought the bare PCBs and all the other bits come from Farnell. I made a few transistor type substitutions - BC546s for BC182s, because the supply voltage was right on the Vceo limit, and MJ21194 output transistors.
Attached Images
File Type: jpg x-modulecloseup.jpg (92.5 KB, 2436 views)
  Reply With Quote
Old 13th August 2003, 10:00 AM   #4
diyAudio Member
 
li_gangyi's Avatar
 
Join Date: Jun 2003
Location: Woodlands Circle
hmmm...interesting...I have a question though...is the flat pack mj21194 better or the TO3 version?? I assume it's the TO3 one...
__________________
Kids in the back seat cause accidents...Accidents in the back seat cause kids...
  Reply With Quote
Old 13th August 2003, 10:37 AM   #5
diyAudio Member
 
Join Date: Apr 2003
Location: Cambridge, UK
Measured performance is excellent:

Power output is about 90W into 8ohms, 180W into 4.

Frequency response is about as flat as I can measure, (<0.1dB, 20Hz-20Khz).

Sine-wave distortion seems to be entirely 2nd-harmonic, at about -80dB, at pretty much all frequencies/power output/load
combinations. The trace below was at about 10W out into 8Ohms, at 5Khz.

No measurable hum / PSU breakthrough at the output, and no detectable instability with long leads, capacitors, loudspeakers, etc.
Attached Images
File Type: png cs2.png (3.3 KB, 1465 views)
  Reply With Quote
Old 13th August 2003, 10:40 AM   #6
diyAudio Member
 
Join Date: Apr 2003
Location: Cambridge, UK
Quote:
Originally posted by li_gangyi
hmmm...interesting...I have a question though...is the flat pack mj21194 better or the TO3 version?? I assume it's the TO3 one...
Given a choice, I'd go for the flat pack one, as it's easier to mount (by basically clamping it to the heatsink with a big bar of aly), and there's no 'case' connection via screws & insulators & whatnot, but the PCB is for the TO3 one.

Cheers
IH
  Reply With Quote
Old 13th August 2003, 11:14 AM   #7
diyAudio Member
 
li_gangyi's Avatar
 
Join Date: Jun 2003
Location: Woodlands Circle
perhaps you can saw off a little part of the PCB...thin out the tracks and drill a few holes for flat-packs to be installed...or use a few pins sticking out for mounting...a little messy looking though...but izzin't TO3 suppossed to conduct heat faster?? Or is the flat pack better in this area...??
__________________
Kids in the back seat cause accidents...Accidents in the back seat cause kids...
  Reply With Quote
Old 13th August 2003, 12:06 PM   #8
diyAudio Member
 
Join Date: Apr 2003
Location: Cambridge, UK
Quote:
Originally posted by li_gangyi
perhaps you can saw off a little part of the PCB...thin out the tracks and drill a few holes for flat-packs to be installed...or use a few pins sticking out for mounting...a little messy looking though...but izzin't TO3 suppossed to conduct heat faster?? Or is the flat pack better in this area...??
According to the datasheets, both have the same junction-to-case thermal resistance (0.7 deg C/W), but ... the flat-pack is rated 200W at a 150 C junction temperature, whereas the TO3 is 250W and 200C.

So, roughly speaking, they are the same thermally, but you can run further into the danger zone with the metal TO3 case.

Cheers
IH
  Reply With Quote
Old 13th August 2003, 12:53 PM   #9
diyAudio Member
 
li_gangyi's Avatar
 
Join Date: Jun 2003
Location: Woodlands Circle
Ok I get the main idea...but dun manufacturer's use the same die for the different packages...if so why the diff?? Maybe I shouldn't be asking here...but I'll ask anyway...
__________________
Kids in the back seat cause accidents...Accidents in the back seat cause kids...
  Reply With Quote
Old 13th August 2003, 01:23 PM   #10
diyAudio Member
 
Da5id4Vz's Avatar
 
Join Date: Feb 2003
Location: lost in america...
Send a message via AIM to Da5id4Vz
Very nice.

XLR and Speakeron connectors, is this for your home Hi-Fi?
Attached Images
File Type: jpg sereo burp.jpg (49.7 KB, 2056 views)
  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
Quad 405-1 Avondale AndrewGM Solid State 0 21st October 2008 12:26 AM
avondale audio modded arcam alpha 5 - AAA5 - anyone tried it? anubisgrau Digital Source 3 16th September 2007 06:37 AM
GB150 (SKA), GB300, NCC200 and chip-amps Dr.H Solid State 2 1st September 2006 06:06 AM
TVC and Avondale mcds Solid State 0 20th October 2004 04:09 PM
Avondale Arcam Alpha 5 t. Digital Source 0 26th May 2003 01:04 AM


New To Site? Need Help?

All times are GMT. The time now is 01:00 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