Lafish
The 57 is a easy load compared to other esl,s
Put a protection board in it and you run any wattage you like.
That said, your question is good one and I would like to know which Pass amp would give the most transparent detailed presentation also for the 57
Regards
David
The 57 is a easy load compared to other esl,s
Put a protection board in it and you run any wattage you like.
That said, your question is good one and I would like to know which Pass amp would give the most transparent detailed presentation also for the 57
Regards
David
If Nelson is lurking around I would like to hear his answer to driving a 57
Don,t care about power output
I use a Vandersteen 2wq sub so bass is not a issue
Any thoughts Nelson?
Regards
David
Don,t care about power output
I use a Vandersteen 2wq sub so bass is not a issue
Any thoughts Nelson?
Regards
David
Thanks all for your input. I too would love to hear Nelson's thoughts. I once heard a 400A driving 57's and while it was way too powerful for them, the sound was remarkable.
I have had customers driving 57's. Neither amplifier or speaker is designed
around a lot of power, so it would be a horse race.
😎
around a lot of power, so it would be a horse race.
😎
Thanks Nelson. Since I have both sets of boards, and the PSU is the same, maybe I'll just build both and swap around.
Sinks arrived yesterday from GB.
purchased directly from Birmingham Aluminium.
Good service nice price and awesome pacing.
http://www.bal-group.com/heatsink_d...=100&calc_air_flow=0&update=Update#calculator
DHL door delivery
The sinks are 84mm x 100mm x 300mm equals 0,282degC/W
Recomended.
Thanx to Jean for posting the Birmingham A. sinks in post 270.
Perfect
purchased directly from Birmingham Aluminium.
Good service nice price and awesome pacing.
http://www.bal-group.com/heatsink_d...=100&calc_air_flow=0&update=Update#calculator
DHL door delivery
The sinks are 84mm x 100mm x 300mm equals 0,282degC/W
Recomended.
Thanx to Jean for posting the Birmingham A. sinks in post 270.
Perfect
An externally hosted image should be here but it was not working when we last tested it.
I ended up buying twice as big as these heatsinks. I had become a heat paranoid after researching. Sigh...
Wow. that should please even the hottest transistors.🙂
Whats the size / brand of sinks you purchased?
P.
It's good to know that I was not totally wrong. I was somewhat skeptical about my heatsinc purchase.
I got second hand ones, so no brand, about 200x280x85mm/ch. It's still cost me a fortune, since I'm building multiple channels.
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Cool, how far are you in the build?.
Pictures🙂
New sinks from BAL is not that expensive though.
Asked for wrong length the first time (lenght equals height of the sink when installed in the amp)
Asked for a quote for 2ea 300mm length ( = height) x 300mm x 84mm.
The price was just over 100euro each incl shipping to Norway.
Shipping cost will of-course wary.
P.
A larger heat sink is a good think ... Lower junction temps will make the devices last much longer.
At a few dollars the piece, how long do you wish them to last.
In present value, the price of a power device nowadays is a mere fraction of the cost 25 years ago.
When I started building power amps with vertical MOSFETs in the mid 1980s, my rule of thumb was to spend half on the output devices and half on the heatsinks.
At a standard die temperature, chances are more likely that the output devices will outlive the amp and/or the owner.
And if they do happen to terminate themselves within 2 decades, the write-off for the power devices will be in the order of a dime a year.
(A bit like yesteryears automobiles, where the engine far outlived the car. Up to this day, there are literally thousands of small motoryachts overhere with a propulsion by a marine converted Mercedes OM636, a car/van diesel engine that hasn't been manufactured for over half a century)
Not cutting corners on heatsinks has a better chance of obtaining the desired operating temperature.
If they turn out oversized after all, it enables to bias the output devices harder : there's never enough quiescent current !
Assuming the heatsink was sized properly to begin with ... and not sure about you, but I sure as heck don't want to go into my amp AGAIN and remove all of the screws, spacers, etc. to replace devices. 😀
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In my experience, a power amp will require a maintenance job long before it reaches end of life. (as a car, a washing machine, yacht, airplane, or anything military)
Ever seen what the goop under power devices in a class A power amp looks like after 15 to 20 ?
Ever seen what the goop under power devices in a class A power amp looks like after 15 to 20 ?