What I have found with the resistors as light bulbs ( incandescent or halogen ) that they are slightly sensitive to vibrations . In other words they can "sound" better dependin where and how they are mounted .
Regarding the dissipation , I am approaching 2 Amps with 2 little fans , the heat sinks and then the Sit transistors cool down to a comfortable temperature with little effort . The fans are not noisy at all .
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I don't know about that particular supply, but I have an adjustable heavy duty switching power supply in my lab and it's terrible for audio work.
michael , you are the man!! i put the heatsink of the 10ohm resistor outside the case, it is very hot but the case , transfo and Caps stay warm 
for the sound no change for me with the wirewound resistor , but i have lost my hexfred bridge for a 3 cents one .. this afternoon if my wife set me free i will put a old good motorola bridge and tell you..
for the sound no change for me with the wirewound resistor , but i have lost my hexfred bridge for a 3 cents one .. this afternoon if my wife set me free i will put a old good motorola bridge and tell you..An externally hosted image should be here but it was not working when we last tested it.
finally it looks like a heavy machine......driving something very dangerous.....
glad you fixed the problem.....
and I am astonished that you do not have the sound difference with the thick film resistors I found astonishing..................................that´s life!
bow with the motorola bridge it sounds superb! , even better than before with the hexfred and the wirewound resistor , so it think the upgrade came from the Thick film res ..
this week / Rcore transfo test and CLC with Rifa PeH200 and hammond 10mh choke ...
this amp 's got so few part , very funny to tweak
What's the voltage/current rating of the Philips pieces? If you're running them at significantly less than rated power, MTBF will increase dramatically...
Roscoe
Hi again...
To whoever....
I wonder if this is a good solution: 2 of these in serie - Halogenlampa 24 V 100 W GY6.35, gives app 12 ohm - and take 1 or 2 resistor 40Watt/1 ohm also in serie. That way you can try both lamps and resistor.
And stay at app 14-15 ohm load! And the biulbs are 4000 hours livingtime. And the voltage over the lamps should be fairly ok. And the Heat Sink for resistors will stay somewhat smaller.
I include a pic of the lamp, and if anybody could leave a comment...
To whoever....
I wonder if this is a good solution: 2 of these in serie - Halogenlampa 24 V 100 W GY6.35, gives app 12 ohm - and take 1 or 2 resistor 40Watt/1 ohm also in serie. That way you can try both lamps and resistor.
And stay at app 14-15 ohm load! And the biulbs are 4000 hours livingtime. And the voltage over the lamps should be fairly ok. And the Heat Sink for resistors will stay somewhat smaller.
I include a pic of the lamp, and if anybody could leave a comment...
Attachments
Yea...
Hi juanitox!
You are right - but with a couple of resistors i serie some of the voltage over the resistor will lower the voltage that stays over the bulbs - but you could also use 3 bulbs= 72 volt/15-16 volt and no resistors.
Could be more than 1 solution on this dilemma ; big heat sink with many resistors - or samller heat sink, w some resistors and 2 or 3 bulbs?
Don`t know for sure still - but some day I will complete this Beast!!
First I must get from Sea to my awaiting B1 Buffer - soon to be finished - if time wills....
Best
Olav
Hi juanitox!
You are right - but with a couple of resistors i serie some of the voltage over the resistor will lower the voltage that stays over the bulbs - but you could also use 3 bulbs= 72 volt/15-16 volt and no resistors.
Could be more than 1 solution on this dilemma ; big heat sink with many resistors - or samller heat sink, w some resistors and 2 or 3 bulbs?
Don`t know for sure still - but some day I will complete this Beast!!
First I must get from Sea to my awaiting B1 Buffer - soon to be finished - if time wills....
Best
Olav
Thougt so...
Yes - it was my intention to get the powersupply together with 3 bulbs = approximately 15 Ohm - then 2 pieces 1 ohm resistor/50watt --- and then measure the ampere through the serie - and the voltage over each individual bulb/resistor. First measure cold, then measure them when they are hot!
That way I will know the load/heat/and resistance on each bulb(in cold/varm condition).
If they change too much when hot - I will build a resistance-chain like generg.
Thats my plan
Olav
Yes - it was my intention to get the powersupply together with 3 bulbs = approximately 15 Ohm - then 2 pieces 1 ohm resistor/50watt --- and then measure the ampere through the serie - and the voltage over each individual bulb/resistor. First measure cold, then measure them when they are hot!
That way I will know the load/heat/and resistance on each bulb(in cold/varm condition).
If they change too much when hot - I will build a resistance-chain like generg.
Thats my plan
Olav
