200k bleeders will run at about 0.6W, so yes, they should be hot, but it shouldn't cause any problem if they're real 2W ones
A9
Well I'm not certain about being real ? Their not burning or discoloured but let's say their hot enough to leave a burn mark on your skin , that worried me , I have some Takman 5w equivalent but much bigger physically, ive been trying to work out exactly what is right for these , so many opinions but surely there must be 1 correct answer ? The caps they need to bleed are 330uf x1 and 33uf x2 is there something better ?? But I don't want one of those big cement types ive seen thrown in , ive spent a lot of time and effort inside the app, but I'm also still learning
Well I'm not certain about being real ? Their not burning or discoloured but let's say their hot enough to leave a burn mark on your skin , that worried me , I have some Takman 5w equivalent but much bigger physically, ive been trying to work out exactly what is right for these , so many opinions but surely there must be 1 correct answer ? The caps they need to bleed are 330uf x1 and 33uf x2 is there something better ?? But I don't want one of those big cement types ive seen thrown in , ive spent a lot of time and effort inside the app, but I'm also still learning
I think you said earlier that the charge bled away quite quickly. Maybe double that time by increasing the resistors, reducing the current - and hence its heating effect.
True, you may increase the resistors value with discharge time increasing proportionally.
330k will run at about 0.37W, 470k at about 0.26W.
330k will run at about 0.37W, 470k at about 0.26W.
A9
Thank you , as I said I'm still on a learning curve but I pay a lot of attention to this , I will see what other resistors I may have , I really question the quality of the ones I fitted , and so happens they were the ebay ones !! Everything else i get from hifi collective , should I increase to 3w ? Much thanks for the replys guys
Thank you , as I said I'm still on a learning curve but I pay a lot of attention to this , I will see what other resistors I may have , I really question the quality of the ones I fitted , and so happens they were the ebay ones !! Everything else i get from hifi collective , should I increase to 3w ? Much thanks for the replys guys
Ok so I have tonight changed the 2 bleedback resistors, luckily I had a pair of Takman 330k , the pink ones in the photo , all is cool 😎 now literally, to my disappointment the grey ones are fake without a doubt , is nothing sacred??
think were both confused now !! so the grey unbranded ones but i suspect fake in their values was supposed to be 200k 2w - the new pink Takmans are 330k 1w - and they are almost cool to touch , Takman rate their 1w resistors to run at something like 5-600w - physically they are big as 2-3w resistors - i know some people just dont worry about cheap stuff but i always buy good quality - as in the case of me risking buying the grey200k's from ebay - look where that ended up !! normally i use hifi collective because i trust their products - Takmans are about £1.00 each - ebay pack of 10 rubbish £1.50 -- NEVER AGAIN !!
Right, I have used some Taskman’s too and they are very solid and have very rigid wires, perfect for my needs (including point-to-point wiring). I’ll never buy these on ebay/aliexpress.
Regards, Gerrit
Regards, Gerrit
Takmans
they are well worth the extra spend - all the other resistors in there are Amtrans - again superb quality and fair pricepoint ---
so my boyuu is still behaving well - very well in fact , at the technicians on Wednesday it had really good traces on the scope - sorry i cant tell you the technical stuff -- thats why i was there !! -- we found it was making about 9w running very cool and under voltages - about 2% distortion at absolute max full gain -- we helped this a little by changing the 500ohm resistance - so now rather than the pair of 1k (500ohm) we removed one on each channel - replaced with a 680r -- that has now given 404ohm resistance - i could see a big difference on the scope - really cleaned up the distortion -- no more can be got from this amp as simply the opt are rubbish !!! -- i might change them for better but now looking at building a pair of kt66-6l6gc pp monoblocks - hoping for about 30w+ -- so will probably leave the boyuu and put my money towards the new scratch build --- my boyuu is powering Klipsch R51-m spkrs -- about 92db sens -- so it does go pretty loud !! - above all its very well behaved -
they are well worth the extra spend - all the other resistors in there are Amtrans - again superb quality and fair pricepoint ---
so my boyuu is still behaving well - very well in fact , at the technicians on Wednesday it had really good traces on the scope - sorry i cant tell you the technical stuff -- thats why i was there !! -- we found it was making about 9w running very cool and under voltages - about 2% distortion at absolute max full gain -- we helped this a little by changing the 500ohm resistance - so now rather than the pair of 1k (500ohm) we removed one on each channel - replaced with a 680r -- that has now given 404ohm resistance - i could see a big difference on the scope - really cleaned up the distortion -- no more can be got from this amp as simply the opt are rubbish !!! -- i might change them for better but now looking at building a pair of kt66-6l6gc pp monoblocks - hoping for about 30w+ -- so will probably leave the boyuu and put my money towards the new scratch build --- my boyuu is powering Klipsch R51-m spkrs -- about 92db sens -- so it does go pretty loud !! - above all its very well behaved -
Has anyone got the specs for the stock power transformer?
Or the model?
I'm particular interested in mA capacity.
Or the model?
I'm particular interested in mA capacity.
I've found nothing in the way of specs for these its pretty poor that the supplier doesn't give it
Spec is quite clear from the circuit diagram. Secondaries are:
5v @ 4A
6.3v @ 3.5A
6.3v @ 1A
315-0-315v [the choke is labelled 200mA, so that's a guide]
...and weighs 3.33Kg
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Hi I think one of my 6N9PJ valves has gone bad. Can anyone recommend an equivalent replacement?