Thanks, I'll just keep the setup I have now, it is similar to yours but split in half for mono block use..Way too small unless you run at low bias.
My heatsink for a pair of clones is 30cm x 12.5x12.5 with a 4" fan and TO3 cans run at about 60C & heatsink at 54C with a bias of 0.5amp per transistor for 36w (according to the calculator). With the fan turned off, the temperature shoots up to over 75C.
It would have been better to use a heatsink drilled for TO3 cans.
They played for a sold hour yesterday while the kids where away. After "a while" one channel starts tu buzz but it goes away if I place a finger on the ground point between the caps.
Two monoblocks, one grounded grid pre amplifier, all with star ground connected to safety earth.
I suspect a loop of some kind between the different parts since the are quiet with just a phone connected to the monoblocks.
Two monoblocks, one grounded grid pre amplifier, all with star ground connected to safety earth.
I suspect a loop of some kind between the different parts since the are quiet with just a phone connected to the monoblocks.
Not trying to be funny but your "main" heatsink is the wrong one for the job and on top of that the position is also wrong that heatsink was design to be upright with the fins in the vertical position to be efficient.Way too small unless you run at low bias.
My heatsink for a pair of clones is 30cm x 12.5x12.5 with a 4" fan and TO3 cans run at about 60C & heatsink at 54C with a bias of 0.5amp per transistor for 36w (according to the calculator). With the fan turned off, the temperature shoots up to over 75C.
It would have been better to use a heatsink drilled for TO3 cans.
Those boards would be better on a flat Fisher SK heatsink.
But it worksNot trying to be funny but your "main" heatsink is the wrong one for the job and on top of that the position is also wrong that heatsink was design to be upright with the fins in the vertical position to be efficient.
Those boards would be better on a flat Fisher SK heatsink.
Not trying to be funny but your "main" heatsink is the wrong one for the job and on top of that the position is also wrong that heatsink was design to be upright with the fins in the vertical position to be efficient.
Those boards would be better on a flat Fisher SK heatsink.
That's why there's a fan fitted so it does work.
It may not suit a perfectionist such as you, but I tried a 30x10x40 finned heatsink for each channel (fins vertical) but wasn't happy with the temperature rise and of course, this type does not lend itself to fan cooling.
Calm down people, yes I am a perfectionist (I do work for the airspace industry) but I was only referring to the low efficiency without the fan Kmj mentioned that the temp went up after disconnecting the fan.
As for the Fisher SK flat heatsink (don't remember number) mine is 300x250x40 (2 off them) and they take an Aleph 30 for the last 7 years without breaking a sweat.
You guys need to loosen up a bit not everything is negative criticism.
As for the Fisher SK flat heatsink (don't remember number) mine is 300x250x40 (2 off them) and they take an Aleph 30 for the last 7 years without breaking a sweat.
You guys need to loosen up a bit not everything is negative criticism.
Not me, mine are cold as... Well, not ice. But cold.Calm down people, yes I am a perfectionist (I do work for the airspace industry) but I was only referring to the low efficiency without the fan Kmj mentioned that the temp went up after disconnecting the fan.
As for the Fisher SK flat heatsink (don't remember number) mine is 300x250x40 (2 off them) and they take an Aleph 30 for the last 7 years without breaking a sweat.
You guys need to loosen up a bit not everything is negative criticism.
You are refering to Batteryman
This is not fun anymore
Everybody knows (or should know) that there is the right tool for each job but even if you use the wrong one (heatsink in this case) you can make it work with some adjustment(s) in your case( KMJ) the use of a fan so problem solved and kudos to you.
In case of Batteryman using a 30x10x40 flat heatsink that he can't attach a fan to and try to get rid of 150W+ of heat and wondering why it's not working is something else.
To use the words of member of the Pass Forum (Nelson Pass ?) about heat sinks, think big and then double it and you will be safe and just for a small example my Mini-A (7W Rms) is attached to a 300x100x40mm heatsink and working like a champ.
Everybody knows (or should know) that there is the right tool for each job but even if you use the wrong one (heatsink in this case) you can make it work with some adjustment(s) in your case( KMJ) the use of a fan so problem solved and kudos to you.
In case of Batteryman using a 30x10x40 flat heatsink that he can't attach a fan to and try to get rid of 150W+ of heat and wondering why it's not working is something else.
To use the words of member of the Pass Forum (Nelson Pass ?) about heat sinks, think big and then double it and you will be safe and just for a small example my Mini-A (7W Rms) is attached to a 300x100x40mm heatsink and working like a champ.
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I think we are misunderstanding each other.This is not fun anymore
Everybody knows (or should know) that there is the right tool for each job but even if you use the wrong one (heatsink in this case) you can make it work with some adjustment(s) in your case( KMJ) the use of a fan so problem solved and kudos to you.
In case of Batteryman using a 30x10x40 flat heatsink that he can't attach a fan to and try to get rid of 150W+ of heat and wondering why it's not working is something else.
To use the words of member of the Pass Forum (Nelson Pass ?) about heat sinks, think big and then double it and you will be safe and just for a small example my Mini-A (7W Rms) is attached to a 300x100x40mm heatsink and working like a champ.
I have two vertically mounted heat tunnels with fans as we speak (and as on 2nd photo.
I got ahold of some others that seemed massive so I asked if you guys thought it was enough.
I am not using the passive heatsinks I asked about and battery man is also using heat tunnels and fans (horizontally mounted).
In other words, just misunderstandings
A tip för ny fellow cloners who are looking for transformers.
The krell uses 2pcs of 2x27V transformers at 400VA each, if memory serves.
You can often find the the Logitech z-5500 speaker system for around $50.
That system includes the following:
1x transformer 2x26.4V and 1x14V at 330VA.
7x TDA7294 chips
2x heatsinks
5x Tangband W3-593SF 3" full range drivers (same as W3-871)
1x Tangband WT-644F 10" subwoofer.
That is what I call a good deal
The krell uses 2pcs of 2x27V transformers at 400VA each, if memory serves.
You can often find the the Logitech z-5500 speaker system for around $50.
That system includes the following:
1x transformer 2x26.4V and 1x14V at 330VA.
7x TDA7294 chips
2x heatsinks
5x Tangband W3-593SF 3" full range drivers (same as W3-871)
1x Tangband WT-644F 10" subwoofer.
That is what I call a good deal
Ok, it took a decade or two but mine are finished.
2x Monoblocks, each with the following properties:
-1x Power transformer 2x26.4v at 300VA
-2x 68.000uF capacitors.
-1x Tunnel heatsink with 92mm fan.
-2x Pairs of MJ15003/15004.
Cable management, what is that?
2x Monoblocks, each with the following properties:
-1x Power transformer 2x26.4v at 300VA
-2x 68.000uF capacitors.
-1x Tunnel heatsink with 92mm fan.
-2x Pairs of MJ15003/15004.
- Dimensions: 350x260x210mm (DxWxH)
- Biased to 630mV per device.
Cable management, what is that?
It's most likely a Chinese joke. With such a correction, the amplifier works as an integrator and at a frequency of 20 kHz we have a triangular voltage at the output.Here is schematic.
Best info ever! Thank You!You can often find the the Logitech z-5500 speaker system for around $50.
1x transformer 2x26.4V and 1x14V at 330VA.
Bought a flood damaged KSA-100B and made seller dismantle it .. this is what I wanted from it.
My plan is to make a pair of "KMA-50" mono blocks, running true! 50W Class A ..., each powered by 1000W transformer and 120000uF/80V-
Further more I am considering adding, regulated power supplies
My plan is to make a pair of "KMA-50" mono blocks, running true! 50W Class A ..., each powered by 1000W transformer and 120000uF/80V-
Further more I am considering adding, regulated power supplies
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