Colin - have you come across any cases out there that can accommodate two amp packs and PSU's? I'm thinking one with built in heat sinks ala some of the First Watt designs.
I've not checked how big the modules are so this case might be overkill, but it sure does look purdy:
Well the Modushop ones look fine. Thanks very much fro the heads-up on those. Which is the size to go for with regard to internal height size (to accomodate the PCBs) and the heatsink capacity...? I'm hoping the "3 unit" ones here would be OK, as the 4 unit ones are taller than I'd like. And what does the "unit" bit refer to...? Is it something to do with the overall heatsink capacity...? If so is "3 units" enough...?
If you look under Spare Parts on the Modushop site it lists the various cases and the bits for them - this includes the heatsinks. It lists the heat dissipation for each of them.
From that info there are two heatsinks per side, together they are .38 degrees per watt, so TOGETHER they are suitable, you just need a method of spreading the heat across the pair. The heatsinks Sovereign is using in the Big Beast are suitable (they are what I am using in my mono blocks) as each one is rated at .4 degrees per watt
And the 190 euro order there includes everything (4x heatsinks, front and back & top and bottom panels...?
And the 0.38 heatsink rating is definitely adequate for the boards...? With regard to spreading the heat load over two sinks, would this be as simple as including some sort of metal plate that spans both heatsinks inside the case, and on to which the board can be mounted, or is there some other way...? Or, is there a simpler case & heatsink option elsewhere...? I should probably go back and read this thead...
I appreciate everyone's patience with this. This is the first time I've ever done anything like this...
It has 4 heatsinks all rated at 0.38C/W thus two a side is 0.38/2 = cool amps at 23W nice.approx.
Now all you need to do is couple both heatsink together to share the energy from the PCB. Try a Ali strip I have some here will cut two bit for you. (My metal work is crap got banned at school and woodwork, and the girls changing room why?)
If this case is suitable I'll also be buying one Ben. 6% discount if two are ordered. I'm away for a week from today but will be ordering on my return.
It looks like the same case I bought for my DAC except this one has heat sinks. Everything we need to build the box is included - apart from feet which I think I had to order from somewhere else.
Colin: Thanks for your offer of the Ali strip. Please add the cost of these to the invoice for the boards! >- Do the feet need to be of a particular height? I've noticed that on both my (your!) TOCA and the ID25 the feet are taller than one normally expects to see...
Paul: Thanks for the reminder about the PFM cases. This Modushop thing continues to tempt me as it's an all in one (cases and heatsinks) package, so I won't be anxious about making sure that parts match.
Brumjam: I'm happy to team up for a discount, but won't the order need to be sent to the same address to qualify...? If not, or if you live close to Gloucester, then I'm up for it.
Sov: That's good. I'll see how it arrives. I'm guessing feet are not a hassle to source if the case arrives without. And, what sort of feet? My intention has been to use something like these:
Ben 50mm should be the min distance from floor or carpet or further if in bathroom, I used door stops good to reject vibration also.
The gap it to allow air flow over the amp it will shut down the current until the max temp is 50C that will reduce power out, so the freezer would be better so chuck out fish, brussels, but keep ice cream, chocolate and pizza for fat Col I hate the others.
Fuse holder and 18-0, 0-18V power input for the transformer.
Bending and mounting the 6Amp diodes in the bridge rectifier.
Mounting the Green Led that is used to generate the ref voltage for the Current control. Note the long leg is near the hole it will be soldered into this is the Anode.
Led with the two 10nF caps behind.
One of the two 33,000uF bulk capacitors note the stripe in the case it is the Negative terminal alway check these or big bang will be louder than the music
.
Mounting the Op-Amp AD820.
The BC337 transistor and the DC offset preset.
The drive transistors BD139 na BD140, see there orientation and the BD140 is on the right. Solder them closed as the PCB acts as a small heatsink. Also mount the BC337 close but not tight to the PCB. See above.
Here is the PCB,sI did for Ben, (thanks for the order Ben could do with more)
On set up insure the IQ preset is Anticlockwise and the DC offset is centre.
PCB 1 , 5Hz - 100KHz Flat PCB 2, 5Hz - 100KHz Flat at full power (15W) in this case.
DC offset -3.2mV 0.3mV
I/P Z 13.5K 13.5K
Damping 1150 1128 with a 250VA transformer tag on.
Phase angle 20Hz - 20KHz -,+ 3.0 deg both PCB,s
Boxed ready to go Ben
Also not the insulators under the MOS FETs a small amount of heatsink compound only OK "U" yes you now who. )
Thanks Colin! =D> ^:)^ 8-> Lovely work. Lovely photos. (Even though this bit is done for me, I would agree with Sov that photos are the single most helpful instructions for me.)
My second response is "thank crikey you've done that for me". Incredible value for money: Hand built by the best designer of Class A amps in the business.
I'm looking forward to getting things started...! I suspect it will be a single step process with each step checked here first. (E.g. "OK I have unwrapped the PCBs...What do I do next...?" or more likely "OK I have snapped the PCB in half while unwrapping it... What do I do next...?") A slow, steady and cautious pace will be the way forward here...
Couple of questions... I notice you seem to have attached the metal plates for coupling the heatsinks...? (Many thanks. ) If so, do I still need the heatsink compound to fix between the plates and heatsinks? If so, is this it, and is that quantity enough or do I need more?
Comments
I suppose our Colin deserves some credit also.
I've not checked how big the modules are so this case might be overkill, but it sure does look purdy:
http://www.modushop.biz/site/index.php?route=product/product&path=66_96_104&product_id=204
Which is the size to go for with regard to internal height size (to accomodate the PCBs) and the heatsink capacity...?
I'm hoping the "3 unit" ones here would be OK, as the 4 unit ones are taller than I'd like.
And what does the "unit" bit refer to...? Is it something to do with the overall heatsink capacity...? If so is "3 units" enough...?
Thank you.
Feeling excited about this Colin. 8->
Should I treat your suggestion on the case as a formal instruction (ie follow it to the letter)...?
Are you able to use these heatsinks that is part of the case, or do you need more heat sinkerage?
I can't see any specs for the heatsinks (other than dimensions) on the modushop website, for me to fail to understand.
I hadn't discovered the spare parts bit.
Will take a good look later.
So the modushop option to go for would be this one...
http://www.modushop.biz/site/index.php?route=product/product&path=66_97_106&product_id=222
(ie 4U 400mm (with 2 heatsinks each side))...
And the 190 euro order there includes everything (4x heatsinks, front and back & top and bottom panels...?
And the 0.38 heatsink rating is definitely adequate for the boards...?
With regard to spreading the heat load over two sinks, would this be as simple as including some sort of metal plate that spans both heatsinks inside the case, and on to which the board can be mounted, or is there some other way...?
Or, is there a simpler case & heatsink option elsewhere...? I should probably go back and read this thead...
I appreciate everyone's patience with this. This is the first time I've ever done anything like this...
Ben can have another colour.
Ben can have puce :-)
for the cases.
It looks like the same case I bought for my DAC except this one has heat sinks. Everything we need to build the box is included - apart from feet which I think I had to order from somewhere else.
Do the feet need to be of a particular height? I've noticed that on both my (your!) TOCA and the ID25 the feet are taller than one normally expects to see...
Paul: Thanks for the reminder about the PFM cases. This Modushop thing continues to tempt me as it's an all in one (cases and heatsinks) package, so I won't be anxious about making sure that parts match.
Brumjam: I'm happy to team up for a discount, but won't the order need to be sent to the same address to qualify...? If not, or if you live close to Gloucester, then I'm up for it.
Sov: That's good. I'll see how it arrives. I'm guessing feet are not a hassle to source if the case arrives without. And, what sort of feet? My intention has been to use something like these:
My freezer needs defrosting, so I will sling the boards in there the moment they are wired up...
Thanks for everyone's ongoing input on this.
I do love to sing in the shower
=D> ^:)^ 8->
Lovely work. Lovely photos. (Even though this bit is done for me, I would agree with Sov that photos are the single most helpful instructions for me.)
My second response is "thank crikey you've done that for me". Incredible value for money: Hand built by the best designer of Class A amps in the business.
I'm looking forward to getting things started...!
I suspect it will be a single step process with each step checked here first. (E.g. "OK I have unwrapped the PCBs...What do I do next...?" or more likely "OK I have snapped the PCB in half while unwrapping it... What do I do next...?") A slow, steady and cautious pace will be the way forward here...
Couple of questions...
I notice you seem to have attached the metal plates for coupling the heatsinks...? (Many thanks. )
If so, do I still need the heatsink compound to fix between the plates and heatsinks?
If so, is this it, and is that quantity enough or do I need more?
Above all, thanks Again Mr. Wonfor.