That's essentially the amp that I'm building for a friend now (except it's dual mono: 330VA transformer, HackerCAP, and QUDOS). I'm wondering how that will compare to the Voyagers you finished for me (with the VBE powering the front-end of the QUDOS).Hi Stack, I don't know about cooling off under load, but I've also noted that the HCR200 modules run fairly warm.
I'm rebuilding my Avondale'd 250 with CAP6's in place of the regulator modules. The NCC220s should be fine unregulated. We'll see.
Trying to make it fit is a constant problem.Hi Mike! You've prompted an interesting idea. The FE regulation is really beneficial. By replacing the regulator boards in the 250 with HackerCAP's fit where the reg boards were, there could be a way to use the space where the original caps were for FE regulators. The Avondale CAP6's are too big for this scheme in a 250 box.
Given how arduous transplanting components can be, my personal preference would be to order the new QUDOS boards, and use the spare NCC200 in another amp.you could have asked Les to sell you the ncc220 qudos bare boards
and used most of the components off you ncc200 only a few differences
This thread is giving me an itch to somehow upgrade my NCC220 MiniCap6 NAP250 case and TX, but I think space would be an issue...Trying to make it fit is a constant problem.
if anyone wants any boards making up for them i have some spare time at the minute these are the boards i built up myself
420181129_142609_1543501695284 by glenn jarrett, on Flickr
420181125_163529_1543163842535 by glenn jarrett, on Flickr
FWIW The pair of beautifully built boards I bought from Avondale 2 years ago did not have the 27R and 100nF fitted.I'm finally pulling together all the spare bits and bobs I have here from previous builds to start on another one. I notice from the above board photo that R4/C9 and R27/C10 are not fitted, but on the Avondale website they are still shown on the board photos. R5 looks to be 10R above
Does anyone have details of the latest and greatest circuit diagram for the Qudos? The one I have here has 27R/100n and 15R for R4/C9 and R5. The photos on the Avondale site appear to show R4 61R and R5 27R, if I'm reading the colour codes correctly!
Cheers
Thanks. Thinking about it, I suppose I'd need to know if there are any value changes elsewhere in the circuit as well in order to leave them out, so I may well just go with the circuit diagram I have.FWIW The pair of beautifully built boards I bought from Avondale 2 years ago did not have the 27R and 100nF fitted.
I have a 250 with Avondale regulator boards and self built 220s.
I have the bias set to 100ma at present and it sounds excellent.
I have used it at this setting for several years and it gets warm but not hot.
Could any of you more knowledgeable chaps comment on the advantages/disadvantages of higher and lower bias settings.