Not yet. It was late when I put it together last night and I didn't want to risk shorting something working at the angle I was. I'll get round to it sometime today.
I was excited by what I heard yesterday when it was only running at 9.5V. Looking forward to trying it again today and I think I'll leave the current heatsink as it is.
Chris
I was excited by what I heard yesterday when it was only running at 9.5V. Looking forward to trying it again today and I think I'll leave the current heatsink as it is.
Chris
Let us know CCS current and impressions later. Well done.it does have a heatsink in my FM4. It is bolted to a metal strap that forms the metal compartment inside the main chassis.
I have just gone and checked.
I can feel the temperature rise around the mains IEC area compared to further away from that end where it is noticeably cooler. That temp rise is due to the heatsink transferring heat from the regulator to the chassis.
Yes the regulator runs hot. I have opened up and felt it. I can imagine many operating scenarios where the regulator may have to work at considerably higher temperatures. Higher temperatures than I have experienced could easily lead to device failure due to operation outside the specification limits.
I have just gone and checked.
I can feel the temperature rise around the mains IEC area compared to further away from that end where it is noticeably cooler. That temp rise is due to the heatsink transferring heat from the regulator to the chassis.
Yes the regulator runs hot. I have opened up and felt it. I can imagine many operating scenarios where the regulator may have to work at considerably higher temperatures. Higher temperatures than I have experienced could easily lead to device failure due to operation outside the specification limits.
Yours must have been a later model taking steps to do something about the reg failure issue as there are no signs of holes for bolts or screws on mine.
Incidentally Andrew, is there a green diode on the pcb near the front of the chassis, to the left as you look at it from the front. There is on mine and it has never worked. Is it worth replacing?
Chris
Incidentally Andrew, is there a green diode on the pcb near the front of the chassis, to the left as you look at it from the front. There is on mine and it has never worked. Is it worth replacing?
Chris
Ah, a Bib playing the Beeb. 
Psycho Killer - The Ukulele Orchestra of Great Britain - BBC Proms - YouTube
Psycho Killer - The Ukulele Orchestra of Great Britain - BBC Proms - YouTube
Back,
how much effort to find out out if the current draw from the new PSU is constant, or nearly constant, or slightly variable or very variable?
Running the FM4 from an isolated supply and connect an earthed scope across the lower value of test resistor. Try 1r0 instead of 8r2. Keep your hands off while powered up.
how much effort to find out out if the current draw from the new PSU is constant, or nearly constant, or slightly variable or very variable?
Running the FM4 from an isolated supply and connect an earthed scope across the lower value of test resistor. Try 1r0 instead of 8r2. Keep your hands off while powered up.
Sorry Andrew I don't have a scope.
I am only running the audio output and tuner section with the external supply. The FM4 transformer supplies the rest which includes the tuning freq display. In fact it will run on just the tuner and audio output only with the freq display blank.
Have you measured the current draw on yours?
Chris
I am only running the audio output and tuner section with the external supply. The FM4 transformer supplies the rest which includes the tuning freq display. In fact it will run on just the tuner and audio output only with the freq display blank.
Have you measured the current draw on yours?
Chris
These are my thoughts after listening to the Salas BiB this afternoon.
This afternoon I finally plugged in the Salas BiB shunt regulator in to power up my old Quad FM4 tuner. The regulator is powered by an external toroid supply rated at 16VAC 1amp for each of its secondaries, only one of which is being used here. I listened first to a solo piano piece and what was immediately gratifying was an absence of glare from the piano notes. It is too easy to find piano notes sounding like wood blocks being knocked together and the resulting brittle glare is difficult to relax into. It also creates a two dimensional image but there was no sign of any of this with this setup; the absence of background noise allowed the dying harmonics inside the piano to be heard and the instrument was presented as a whole. With previous power supplies the piano often sounded an instrument of two halves, one connected with the right hand and another involved with the lower end of the keyboard. I think it is the ability to reveal the low level detail that allows the instrument to be seen as a whole. This ability to create a satisfying musical whole was apparent from BBC’s next offering.
Schubert’s unfinished was to follow played by the Scottish Symphony Orchestra.
Again the absence of background noise allowed individual instruments not only to be enjoyed in their own right with full and realistic dynamics but also to gel homogeneously with the rest of the orchestra. I have often listened to instruments appearing from the orchestra as though escaping from a dark background which is not unpleasant. But with the Salas in place the instruments can be heard against a background of other more subtle musical images such as quiet strings and woodwind. And these instruments don’t disappear at low sound levels so the musical image is held together as a unit. I haven’t enjoyed so much before the strings of the double basses and cellos holding their own as the rest of the orchestra joined. In the past they became lost in the overall sound but this power supply kept everything in focus. Timbre and depth of musical image are very good allowing one to sense the human hand and body at work.behind the instrument. Strings are rich and possess depth. Lesser supplies can emphasise the upper registers of violins for example, which can fatigue but also prevents the richer undertones from being heard and again prevents us from experiencing that human element to the playing. Percussive dynamics are excellent but don’t overwhelm the more subtle harmonics behind the sound. Bass lines are well delineated and the supply creates a satisfying depth to the soundstage and illuminates very nicely the subtle echoes running around the performance space at the end of each movement.
I like this supply a lot. I don’t have shares in the company so I’m just writing enthusiastically because it is always great to enjoy the company of an old friend in great form—my old tuner that is. A power supply can make all the difference to good listening; it is not just my imagination.
This afternoon I finally plugged in the Salas BiB shunt regulator in to power up my old Quad FM4 tuner. The regulator is powered by an external toroid supply rated at 16VAC 1amp for each of its secondaries, only one of which is being used here. I listened first to a solo piano piece and what was immediately gratifying was an absence of glare from the piano notes. It is too easy to find piano notes sounding like wood blocks being knocked together and the resulting brittle glare is difficult to relax into. It also creates a two dimensional image but there was no sign of any of this with this setup; the absence of background noise allowed the dying harmonics inside the piano to be heard and the instrument was presented as a whole. With previous power supplies the piano often sounded an instrument of two halves, one connected with the right hand and another involved with the lower end of the keyboard. I think it is the ability to reveal the low level detail that allows the instrument to be seen as a whole. This ability to create a satisfying musical whole was apparent from BBC’s next offering.
Schubert’s unfinished was to follow played by the Scottish Symphony Orchestra.
Again the absence of background noise allowed individual instruments not only to be enjoyed in their own right with full and realistic dynamics but also to gel homogeneously with the rest of the orchestra. I have often listened to instruments appearing from the orchestra as though escaping from a dark background which is not unpleasant. But with the Salas in place the instruments can be heard against a background of other more subtle musical images such as quiet strings and woodwind. And these instruments don’t disappear at low sound levels so the musical image is held together as a unit. I haven’t enjoyed so much before the strings of the double basses and cellos holding their own as the rest of the orchestra joined. In the past they became lost in the overall sound but this power supply kept everything in focus. Timbre and depth of musical image are very good allowing one to sense the human hand and body at work.behind the instrument. Strings are rich and possess depth. Lesser supplies can emphasise the upper registers of violins for example, which can fatigue but also prevents the richer undertones from being heard and again prevents us from experiencing that human element to the playing. Percussive dynamics are excellent but don’t overwhelm the more subtle harmonics behind the sound. Bass lines are well delineated and the supply creates a satisfying depth to the soundstage and illuminates very nicely the subtle echoes running around the performance space at the end of each movement.
I like this supply a lot. I don’t have shares in the company so I’m just writing enthusiastically because it is always great to enjoy the company of an old friend in great form—my old tuner that is. A power supply can make all the difference to good listening; it is not just my imagination.
My pleasure.
I have increased the size of the heatsink from 10degC/W to 3.6C/W and I can now hold my finger on the metal near the mosfet without discomfort. On the downside I can't get the lid on the box now. It might be possible to get away with 5degC/W.
