Moving Ahead
Well-Known Member
bravo
thanks for the welcome!
I am very curious how you will rate your 6060 once upgraded. as I see in your signature you also own a 6120. is that restored, too? would be curious about the differences. and how compares the 6055 re bass and treble sweetness?
.....
eschenborn
So you're ready to go to the dark side?
Let me reinstate I have not had the pleasure of seeing a 6060 in the flesh so what I pass on you can take with a grain of salt.
Firstly as you can appreciate it is a historical piece and one must appreciate this- warts and all.
And secondly I don't know about your str unit but I'd rather have a lobotomy than work on the 1120 again. So proceed at your own peril.
The 1120 should be your big brother- so I can assume it shares the same DNA. Yes I did change out the sC631,sC632. They were all 430hFE +-5%. I replaced with low noise type with higher gain than the originals. I than tied a knot in the head amp feedback. I replaced with old resistor to match the original look so no one will know any different. So yes I kept the circuit the same. I doesn't achieve a zero noise floor but man I can hear a pin drop.
In addition Q1 on the main amp board-c631 I changed out too. I applied a little pressure to the brake pedal here cause of the earlier changes.
Now the heat sink has dropped about eight degrees as the volume is about 10 o'clock. Which works for me as the thermal compensation diodes can now have a holiday.
The unit I have brings much joy.
I think that the degradation of caps resistors etc. leads to a path of eventual sonic critical mass...just before failure or going out of spec it seems like the fatigued parts pass a little more of a relaxed sagged signal as opposed to a fast critically clean signal...and frankly it's very pleasent if your listening closely...I think you experienced that on initial listening..I think cap replacement should be approached pretty cautiously..You might feel the same way as I do because it seems like there is recap fever going on with new "used" purchases..When maybe just a minor tweaking is all that's needed...I'm not referring to qualified experts doing a valid renovation like yourself. But people instantly recapping everything , kind of because everybody else says they did....sort of like audio peer pressure....Your thoughts are eagerly awaited, as you obviously get it.thanks. that's very interesting. which transistors (numbers) did you use then?
I am always flirting with the dark side. although I am hesitating to do this change, because it is not my only amp, and it is fully functional. the legacy thing. and I have used up all my spare time for the moment. but it would be interesting to hear what difference there is.
I was wondering about how it sounds without NFB altogether. not sure if this is possible in that circuit, as any transistors, even low noise, may introduce some hiss. but what I heard in the low end when I shortly eliminated the pre-amp global NFB circuit was a very full low end.
can aging transistors cause a different sound balance? or was the amp designed like that?
@FOH Engineer : the strange thing is that my 6060 unit is on the border of too bright. super revealing and extremely resolving with some recordings, to bright and sharp with others. this is what I meant with "to solid state". my experience is that normally the older the vintage SS gear is, the less pronounced is the SS flair of it, and the nicer it is to listen to. so for me the 6055 was a step down from the 6050. in that logic, and due to many happy owners posting their bliss, I was thinking that the 6060 was even better. but there might be wide variations between single units of the same model.
I think that the degradation of caps resistors etc. leads to a path of eventual sonic critical mass...just before failure or going out of spec it seems like the fatigued parts pass a little more of a relaxed sagged signal as opposed to a fast critically clean signal...and frankly it's very pleasent if your listening closely...I think you experienced that on initial listening..I think cap replacement should be approached pretty cautiously..You might feel the same way as I do because it seems like there is recap fever going on with new "used" purchases..When maybe just a minor tweaking is all that's needed...I'm not referring to qualified experts doing a valid renovation like yourself. But people instantly recapping everything , kind of because everybody else says they did....sort of like audio peer pressure....Your thoughts are eagerly awaited, as you obviously get it.
Does the UF4006 diode need to be rated 3A/600V? Can’t seem to locate that size at Mouser or Digikey.