Destroyer x Amplifier DX HDII version.

[meanman1964]

Originally posted by konkret
Hi meanman,

as a new member of diyaudio.com
I do not have access to other member e-mail addresses yet,
so I cannot contact you this way.
Since you should not have this problem,
please do not hesitate to contact me via my member e-mail address.

Cheers,

----------
konkret

yOU CAN MAIL ME PATRICK.ROVERS@SCARLET.BE

[dudaindc]

Hi Nordic
Please count me in for a stereo set.
(Pending final costs I may increase that...)
Cheers!

[Harry3]

Hi,
What is the pitch for the plastic caps eg 100nF?
Hopefully there is provision for 5 and 10mm pitch on the PCB.
Also is the spacing for the resistors wide enough to take the Vishay RN60D series resistors?

Regards
Harry

[Nordic]

Hi Harry

I am not sure, but I believe those resistors are larger than the 7mm pitch of standard 1/4W metalfoil resistors. The witdth should not be a problem, as few resistors are "blocked in", alll resistors on the board are 7mm pitch, except the 3 power resistors which were spaced for non inductive R's, the 2 47R resistors at the diff pair also allows for 9mm pitch and input resistor is a 5mm 1/8W jobby (space constraints). In fact I mounted my input cap and this resistor "offboard" in my unit to allow for larger input caps... you can simply solder a 180R resistor to the positive pin of the input RCA socket...

To keep size of PCB (cost) and inductances low, I had to minimise traces, and in the process, component sizes....

Trust me, there is not a single "audiophile" component in my box, and it sounds better than anything, I have had the honour to listen to... Small caps are all 5mm pitch... you ca fit a mica cap in the space provided for the Cdom cap... I did this in mine...

If you'd like to start stocking up, you will need 20 x 100nf caps if you also want to bypas elcos... else you will need 12 of those caps for the 2 channels....(I can provide these at a cost of about $2 as they cost me only about 9 south african rand + VAT) Same type as provided with the Twisted pair Kits, not sure ofthe brand... they are little yellow caps, they work well.

I can also provide the resistors at about the same cost... there are about 50 resistors between the 2 channels...

Welcome to the new faces, we are at 13 sets (26 boards) after just one weekend...

[AndrewT]

Hi,
0.28inch (7mm) is very small.
The normal minimum pitch for low watt resistors is 0.35inch (8.9mm). Most PCBs use 0.4inch or more for minimum resistor pitch.

When space is available I always recommend at least dual pitch for as many caps as possible. But you are excused when PCB space is scarce.

[Nordic]

I have seen the larger resistors RS sells a .333W unit in this size..., but 7mm pitch worked just fine... legs take a standard 90degree corner straight down the hole... with no unnessecary leads.. The issue is to not go to a larger PCB size... without going for miniature parts...

I have constructed 2 units with no construction problems up to now.. did get the idea to provide holes for a BG or other NP elco type input caps though...

I know there are those who believe in "audiophile" parts, but Carlos made me experience for myself that topology means more in the big scheme of things... I still believe in nice input caps though (big fan of Ampohm brand), but without fast swapping AB, I will not be able to say wich one I am listening to...

I didn't have any more nice large film caps to aid in comparison listening, will get a few diffirent ones of e-bay again... and I like my chipamp best with the ampohm jobbies... so I settled for cheap hitano non-polar 10uf cap to get the amp boxed again, and the livingroom cleaned up.....I would never have believed this cheap cap can sound so "good"

[dw1narso]

Hi Nordic,

count me in for a stereo channel... (a PCB pair, right?)

I would be interrested to get as many parts as possible from you too to build it, if you have surplus to sell...

(I'm living in a country of very little DIY offerings... even for some chips like LM3875 or audio transistors I have to order overseas...)

I'm contactable at david_winarso at yahoo dot com

Thanks,
---
David

[A'af]

sorry out of topic..

howmany LM you need from innerseas dwinarso, let me know...

all the best,
a'af

[Greg Erskine]

hi Nordic,

1 pair of PCBs (2 off) for me thanks.

regards
Greg

[Nordic]

Wonderfull and welcome on board, sorry for not posting today... busy with my first SMD project... boy 0805 is alot smaller than I thought.... but, I have a large supply on a dead PC motherboard...
Only have to buy 2 values to complete the boards... I guess 1M and 470k, is not all that popular on PCs.. Maybe I should just get 1M and paralell 2 for 470k...


Managed to reduce my Pedja Rogic buffer to 3 x 4 cm...yep it will fit in a matchbox...but, I am dead tired now...

The group buy looks more or less like a sure thing at this point in time... I will let it run on till Friday, if noone objects, before finalising costs...

David we will sort you out partswise.... Let me know if you can get large electrolytics though say from 2200u to 10000uf under 25mm diameter, 50V.

Also if you can get 2sc5200 and 2sa1943 localy... else we will have to get you some off ebay... my regular suorce, sell fake ones... I can get real ones localy at good prices through the official distributor... but need to take a whole tube... will only happen if more people need those...


Welcome Greg... father of the DX amp layout...!!!!!!