Amp Camp Amp - ACA

... I assume this new heat sink will be more than substantial. I have a student version of Autodesk Inventor, so I modeled the profile, and after I trim it down to 8.5"x4.5" to fit the case, it will be around 1.22pounds, and have 435 square inches of surface area. Rather than make another assumption, how would I go about calculating the heat dissipation of the new heat sink.

Two thoughts,
First is that each amp board needs to dissipate 36 Watts all the time (class A) so 72 Watt for a stereo amp.
Second is the official case has 2 heatsinks, one per amp board, both are 8'' x 3.25'' with 1.5'' fins. Then the ACA still runs hot. How hot depends on ambient temperature of course.

I suspect you will still be short on free air cooling with your revised heatsink.
 
Yay! My chassis was deleiverd today. Sadly, it was not delivered to me. What are the chances of FedEx finding my box?
I had the same 3 weeks ago, turned out it had never left the depot but had been mysteriously scanned as delivered and signed for by the driver!! A polite complaint got it sent out next day. I suspect FedEx are as busy as all other couriers at the moment and there are pressures to hit unobtainable targets.
 
I had the same 3 weeks ago, turned out it had never left the depot but had been mysteriously scanned as delivered and signed for by the driver!! A polite complaint got it sent out next day. I suspect FedEx are as busy as all other couriers at the moment and there are pressures to hit unobtainable targets.

If you call FEDEX , they can call the driver and see what happened. Do it as soon as possible.

Done. I have zero faith in FedEx. Does anyone know if the chassis shipment is/was insured?
 
All PDA's used by couriers will have time and location tracking accurate to within about a meter or so. Also, due to covid, couriers are not requesting customer signatures on the doorstep but the recipients name should still be entered into the PDA when the driver signs on the customers behalf. I recommend that you contact FedEx again and request the time and location data for your delivery. For sure the person taking your call won't have this to hand but they need to find someone who does!!
 
All PDA's used by couriers will have time and location tracking accurate to within about a meter or so. Also, due to covid, couriers are not requesting customer signatures on the doorstep but the recipients name should still be entered into the PDA when the driver signs on the customers behalf. I recommend that you contact FedEx again and request the time and location data for your delivery. For sure the person taking your call won't have this to hand but they need to find someone who does!!

I've got the delivery PDF, time and who signed. Frustrating, it's not like this building is hard to find. The office was closed at the time, and no "K. Kirby" here. Grrrr.....
 
But its the gps location data attached to the final delivery scan that you need to get FedEx to retrieve for you. This is internal FedEx only data, they should be able to print out a google earth type location map that marks the spot of the final delivery scan. Suspicious if they can't.
I also imagine it will make life easier dealing with the modushop if you make this request.
 
But its the gps location data attached to the final delivery scan that you need to get FedEx to retrieve for you. This is internal FedEx only data, they should be able to print out a google earth type location map that marks the spot of the final delivery scan. Suspicious if they can't.
I also imagine it will make life easier dealing with the modushop if you make this request.

I'm assuming FedEx is working the location issue with the driver, but like I said, I have zero faith in their ability to find it.

Hurry up and wait, I guess.
 
You don't need the results of a conversation with the driver you need the location data automatically generated when he or someone scanned your parcel barcode as delivered. This is available right now if you call FedEx!

I don't see it as my job to find the box they mis-delivered! I checked the small store in my building and the apartment next door. Now it's on FedEx.

ETA: Just got a call from FedEx, they are at least looking for it!
 
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Two thoughts,
First is that each amp board needs to dissipate 36 Watts all the time (class A) so 72 Watt for a stereo amp.
Second is the official case has 2 heatsinks, one per amp board, both are 8'' x 3.25'' with 1.5'' fins. Then the ACA still runs hot. How hot depends on ambient temperature of course.

I suspect you will still be short on free air cooling with your revised heatsink.

Thank you, very useful information (that I probably should have already known). I'm not sure where I came up with the number, but I thought it was 20 watts per board. I guess what I will do is start by temporarily mounting both boards to the new heat sink, with out any other fitment for the case, power them up and just monitor the temperatures. I know cooling wouldn't get any better if I trim it down, so if there is insufficient cooling at that point, I won't waste any more time going that route

Thank you again.
 
The design comes from this thread "Mark Audio Alpair 10.3/A10p MLTL". Been using them with various chip amps but the one fault was occasional brightness with some recordings, this is not the case with the ACA.
My pair of ACAs are on the 2 outer shelves, a big part of the appeal for me was the small case to fit the amps on the shelves. I went for the deeper version of the case to compensate for the lack of airflow and all seems fine temperature wise.
My favourite speakers are however the TABAQ with P830987, I have these in another room with an F5. Worth checking out the long running TABAQ thread if you are unfamiliar, they must be the best, simplest and cheapest diy build ever!!

Coming from a world of multiway speakers with crossovers, my brain really can't understand the single full range drivers. Not to mention I have dual 21" subs and can't imagine any fullness on the bottom end without some support from subs. They must work but it seems illogical.

I'm in the middle of a Elsinore build that is sitting idle in my shop. Its a mildly complicated cabinet with a complicated crossover (at least to me). I keep looking at the full range driver options thinking I might try a pair to see what they're like. Thanks for posting the pics. Nice set up.
 
Coming from a world of multiway speakers with crossovers, my brain really can't understand the single full range drivers.
Years ago I used to drink tea with 2 spoons of sugar but moved over to no sugar. If someone gives me a cup now with sugar I can't drink it, horrible! I'm the same with multiway speakers, grew up with them but just can't listen to them anymore!!!