I do love big caps. They just make you feel better about things in general.I assume the last two are the Icar motor ru s you were talking about. I use GE in my tube preamp. Very nice indeed. You will enjoy it thoroughly.
yes, they are Icar.From what GE comes?
I choose rifa`s because they have very long life(60000h @ 85C), high ripple curent, very low ESR and the price is acceptable(~15euro/piece, farnel delayed a little bit the order and for this they offered me a discount)
yesterday morning my other amp(toshiba sc330) died.I used with him a tube pre(6h8c+6h9c).all the time when I was starting the hv power supply of the pre a noise was taking the amp vumetters at ~20Wpc(volume control was at maximum all the time on amp side because I use the pot from the pre) and yesterday the power transistors on one channel didn`t take it no more and blew away(on one channel I have originals on the other that blew away I have BD equivalents, I received the amp like this).
now I wonder are there any chances that this will happen with aleph too?(this time I am planning to start the amps after the pre)
does it worth it to use a speaker dc protection & delay?
forgot to mention that the pre is capacitor coupled with the amp
ps with the speakers didn`t happen nothing cause on the amp i have a switch to couple them and that one is the last I am switching ON
I choose rifa`s because they have very long life(60000h @ 85C), high ripple curent, very low ESR and the price is acceptable(~15euro/piece, farnel delayed a little bit the order and for this they offered me a discount)
yesterday morning my other amp(toshiba sc330) died.I used with him a tube pre(6h8c+6h9c).all the time when I was starting the hv power supply of the pre a noise was taking the amp vumetters at ~20Wpc(volume control was at maximum all the time on amp side because I use the pot from the pre) and yesterday the power transistors on one channel didn`t take it no more and blew away(on one channel I have originals on the other that blew away I have BD equivalents, I received the amp like this).
now I wonder are there any chances that this will happen with aleph too?(this time I am planning to start the amps after the pre)
does it worth it to use a speaker dc protection & delay?
forgot to mention that the pre is capacitor coupled with the amp
ps with the speakers didn`t happen nothing cause on the amp i have a switch to couple them and that one is the last I am switching ON
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Always turn power amp on last. It prevents any nasties from getting through when turning on other small signal stuff. Small to large at turn on and opposite for power down. Sounds like pre has some nasty DC at turn on. Doesnt make sense that it is capacitively coupled ic its turn on affected power amp. AJ will be fine, especially if you have speaker with crossover.
measured right now dc at output of the pre and when I power on the hv ps the multimetter shows me 20V.how this could be possible if the is a 4uf/280V x2 class polypropylene cap on the output?
Do you have schematic? Sound like you may need slower B+ ramp up. Just guessing without schematic, maybe even with 😀
Toobz not my game, but my guess is B+ ramp is too fast, but can't say for sure. Maybe PSU s hematics and pics would help with diagnosis. Sometin very wrong.
the hv ps of the pre uses 5u4g(if I remember corectly) tube rectifier, after this clclc, two ob2 (tied in series between them, each one is 150V stabiliser) and after these a rcrc filter
Turn on and see if voltage at output slowly goes away. If so, I think ramp up is issue, as I don't see another way to have same results.
bloody bleeding resistor on output
is missing , of course
and yeah - short circ between two headphones
next time use 220Vac from wall instead of amp , to prepare speakers for listening session
is missing , of course
and yeah - short circ between two headphones
next time use 220Vac from wall instead of amp , to prepare speakers for listening session
maybe yes . maybe not
whatever - powering tube pre in same time or after power amp is ......... just not worshiping as it needs to be ..........
either culprit is in SS HV or elsewhere
who cares ?
either put delayed mute relay on pre output , or use da unshorted circuit between two headphones
whatever - powering tube pre in same time or after power amp is ......... just not worshiping as it needs to be ..........
either culprit is in SS HV or elsewhere
who cares ?
either put delayed mute relay on pre output , or use da unshorted circuit between two headphones
I have bleeding resistors on output of 100K.
Could there be any problem for the input jfets of the aleph if on the input arrives 20Vdc and the amp is shut down?
in the future I thought to redesign the preamp and I think mute relays will be an option
Could there be any problem for the input jfets of the aleph if on the input arrives 20Vdc and the amp is shut down?
in the future I thought to redesign the preamp and I think mute relays will be an option
that's not DC , but surge AC voltage
it happens in moment of gas tubes firing
see datasheets
so - I repeat - either muting relay on pre out , or power up power amp about 1min later
don't make big issue of it - normal behavior
it happens in moment of gas tubes firing
see datasheets
so - I repeat - either muting relay on pre out , or power up power amp about 1min later
don't make big issue of it - normal behavior