Michael, have you compared the sound using the switchers vs. a simple CRC passive supply?
I don't know if Vicors sound better, but you often can pick up an appropriate model from eBay without too much waiting or searching.
I don't know if Vicors sound better, but you often can pick up an appropriate model from eBay without too much waiting or searching.
Juanitox! Excuse me not asking for the heat problems, but.....
For the sound, did you here the same big jump forward in precision and clarity I meant to here after changing to thick film resistors.....?
For the sound, did you here the same big jump forward in precision and clarity I meant to here after changing to thick film resistors.....?
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..
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!
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!
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That's great! And, it looks great too.
Now you can focus on dialing-in the sweet spot for your speakers/taste. It may take a little time, but you'll have fun.
Well done 🙂
Now you can focus on dialing-in the sweet spot for your speakers/taste. It may take a little time, but you'll have fun.
Well done 🙂
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
hi!
Ohm`s law: Volt x Volt / Watt= 24x24 divide on 100= app 5,7 ohm. but it depends somewhat on the current. so app 1,7 Ampere....
Gets you nearby I think
Olav
Ohm`s law: Volt x Volt / Watt= 24x24 divide on 100= app 5,7 ohm. but it depends somewhat on the current. so app 1,7 Ampere....
Gets you nearby I think
Olav
You really want to measure the bulbs at the voltages and currents you'll be using them. The resistance changes with filament temperature.
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
