So I guess in your opinion a 7lb slab of solid aluminum should do it??? It's pretty darn big. I'll use one slab for each channel and bolt them into the sides of a rackmount wooden case.
Lets see, there are two aluminum plates(14lbs), one 5kva tranny(62lbs), all of the circuitry and transistors(about 3lbs), the wooden case(about 15lbs)..... that totals to 94lbs
That's one heck of a heavy amplifier. It'll take quite a strong person to mount that puppy into a rack!!!! I think at that weight and size it'll have to sit either on the floor or at the very bottom of a rack.
The size of the heatsinks means the amp will be a 12U tall unit. Then 22" deep and 18" wide. This thing will be huge! 
Lets see, there are two aluminum plates(14lbs), one 5kva tranny(62lbs), all of the circuitry and transistors(about 3lbs), the wooden case(about 15lbs)..... that totals to 94lbs
That's one heck of a heavy amplifier. It'll take quite a strong person to mount that puppy into a rack!!!! I think at that weight and size it'll have to sit either on the floor or at the very bottom of a rack.The size of the heatsinks means the amp will be a 12U tall unit. Then 22" deep and 18" wide. This thing will be huge!
Duo...I don't know if that will work for a sink or not. Here's why. Heatsinks have fins and bases. Right? Some have thick bases, some have thin bases. The ones with thicker bases take longer to heat up, the ones with thinner bases give the heat to the fins faster, but if the surface area is the same, ultimately...as the sink heats up...its all about dissipation. How much heat can the heatsink get rid of. For instance, if you had a 50 lb block of aluminum that was 2" thick and the same dimensions as yours...(discounting that it has slightly high surface area b/c of the extra thickness) it'd take a long time to heat up maybe, but only be able to dissipate slightly more heat....so you'd be limited in the time you'd be able to use it. Also, if you want your amp to run into lower loads, you definitely need to make your heatsink adquate. Look at this thread:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=12238&highlight=heatsinks+source
please someone give a 2nd opinion here
-Matthew K. Olson
http://www.diyaudio.com/forums/showthread.php?s=&threadid=12238&highlight=heatsinks+source
please someone give a 2nd opinion here
-Matthew K. Olson
Hi there,
maybe I'm a bit late telling this, but maybe it's an idea of using a different rail for the voltage amplifier and the current amplifier?
If you connect a 2x6 trafo "above" (or in series, I don't know how you call it) with the BIG transformer, you have a higher possible output-voltage, witch means: more output power at the same rail-voltage, or lower dissipation with same power and lower rail-voltage.
This was just a thought, maybe you have already considered it and you don't think it useful.
Grtz, Joris
maybe I'm a bit late telling this, but maybe it's an idea of using a different rail for the voltage amplifier and the current amplifier?
If you connect a 2x6 trafo "above" (or in series, I don't know how you call it) with the BIG transformer, you have a higher possible output-voltage, witch means: more output power at the same rail-voltage, or lower dissipation with same power and lower rail-voltage.
This was just a thought, maybe you have already considered it and you don't think it useful.
Grtz, Joris
Duo what I did with my home made heat sink was bolt a peice of 2x2x1/4 aluminum angle and placed my transistors on it....I have 10 To-3 cases on each heat sink....I formed numerous U channels each one is .750" smaller than the other...I think there is 8 on each plate....I did paint the fins with a mixture of flat black (high heat) and gloss black (about 20%) to give a nice satin look....I tig welded all the U channels together and then applied thermal compound and bolted it to my 6x.375inch bar stock ...overall It looks pretty good for a home made job and as far as performance maybe not the best but it keeps my devices cool so I have the design criteria in my beleifs...I do have some small fans mounted but found out they were not needed so I left them not hooked up
Cheers!!The DIRT®
Cheers!!The DIRT®
"maybe I'm a bit late telling this, but maybe it's an idea of using a different rail for the voltage amplifier and the current amplifier?"
Maybe you should read the whole thread?
"I want to make a seperate power supply tier that will supply the LTP and VAS with a higher voltage... How much voltage should I use for this tier?"
How much of this do you really understand?
djk []
diyAudio Member
Online
Registered: Feb 2001
Post #52
"How many tiers do you think I need in my amp?? I was thinking of using just one. Would it be better to use more?
You will also need a small supply of ±85V at 100mA or so for the voltage gain stages of the amplifier. And a Baker clamp to both the ±40V tier and the ±80V tier.
06-02-2003 02:52 AM
A flat aluminum plate is called a griddle, works real well to cook food.
A heatsink for a 2KW power amp will have LOTS and LOTS and LOTS of heatsink area, without the ±40V tier the amplifier will have to get rid of twice the amount of heat that the Crown does.
Parts with MPS, MJ, MJE, etc, pre-fixes were originally Motorola part numbers. In 1999 ON Semiconductor bought Motorola (more or less).
Maybe you should read the whole thread?
"I want to make a seperate power supply tier that will supply the LTP and VAS with a higher voltage... How much voltage should I use for this tier?"
How much of this do you really understand?
djk []
diyAudio Member
Online
Registered: Feb 2001
Post #52
"How many tiers do you think I need in my amp?? I was thinking of using just one. Would it be better to use more?
You will also need a small supply of ±85V at 100mA or so for the voltage gain stages of the amplifier. And a Baker clamp to both the ±40V tier and the ±80V tier.
06-02-2003 02:52 AM
A flat aluminum plate is called a griddle, works real well to cook food.
A heatsink for a 2KW power amp will have LOTS and LOTS and LOTS of heatsink area, without the ±40V tier the amplifier will have to get rid of twice the amount of heat that the Crown does.
Parts with MPS, MJ, MJE, etc, pre-fixes were originally Motorola part numbers. In 1999 ON Semiconductor bought Motorola (more or less).
Joyce bought a truckload of used Crown M2000s a while back. Several had to be scrapped out. See if she has any of the heatsinks left, she had them on eBay for a while.
soundvalves@hotmail.com
I bought out the balance of her Hafler DH500 heatsink tunnels, about 50 pcs.
soundvalves@hotmail.com
I bought out the balance of her Hafler DH500 heatsink tunnels, about 50 pcs.
Well, I think I'm going to make fins to go onto this aluminum plate to make more surface area.
The plates are the perfect size to use for the sides of a case since the heatsink is just slightly taller than the transformer I intend to use.
I have two such plates and intend to mount them on the sides of the cabinet. The back and front will be MDF board and the top will be hardwood, all of the wood will be stained and lacquered.
The plates are the perfect size to use for the sides of a case since the heatsink is just slightly taller than the transformer I intend to use.
I have two such plates and intend to mount them on the sides of the cabinet. The back and front will be MDF board and the top will be hardwood, all of the wood will be stained and lacquered.
You must have used the wrong link. http://wingzero.ath.cx links to my mailserver right now.
It won't spam you at all.
It won't spam you at all.
whew, another question.... This is for those with lots of heatsink experience.
I have these two metal plates and there will be ten transistors for each plate. I want to leave the collectors of each transistors connected to each plate directly.
I have two options here:
1. I can have 5 matched pairs on each plate with thier collectors common for the output. This means that the plate would be connected to the speaker output. I guess this means I'd have a very easy way of connecting fat speaker cables.
2. I can have all the PNP transistors on one plate and all the NPN's on the other and use the plates as supply rails. This means the amp would be emitter loaded. This also means that if you run one channel, the other channel's transistors will be heated.
Which seems to be the better idea??? I really don't want to try insulating the collectors from the heatsink, especially since I'm going to have the transistors and heatsinks fairly open on the sides of the amp. I mean, yeah, the whole plate on each side will be live but it's better than making it easy to short the transistor to a grounded heatsink...
I have these two metal plates and there will be ten transistors for each plate. I want to leave the collectors of each transistors connected to each plate directly.
I have two options here:
1. I can have 5 matched pairs on each plate with thier collectors common for the output. This means that the plate would be connected to the speaker output. I guess this means I'd have a very easy way of connecting fat speaker cables.
2. I can have all the PNP transistors on one plate and all the NPN's on the other and use the plates as supply rails. This means the amp would be emitter loaded. This also means that if you run one channel, the other channel's transistors will be heated.
Which seems to be the better idea??? I really don't want to try insulating the collectors from the heatsink, especially since I'm going to have the transistors and heatsinks fairly open on the sides of the amp. I mean, yeah, the whole plate on each side will be live but it's better than making it easy to short the transistor to a grounded heatsink...
Hi.
Right said Pinkmouse.
Duo,you have to redesign the whole thing.It's not a good idea.
Bellow is how I'm going to resolve this thing with the isolated
heatsinks in RMX4050.Maybe it will be usefull for you.
Dimension of heatsinks:120mm wide,120mm tall and 360mm deep
Regards.
Right said Pinkmouse.
Duo,you have to redesign the whole thing.It's not a good idea.
Bellow is how I'm going to resolve this thing with the isolated
heatsinks in RMX4050.Maybe it will be usefull for you.
Dimension of heatsinks:120mm wide,120mm tall and 360mm deep
Regards.
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