If you are into water cooling, why not use a computer water cooling system? I was planning to do so but I am concerned with too much cooling. I am affraid that unless I ran thermistors or some sort of thermostat the amp may not warm up enough to sound good. Hey, maybe I can use it as a water heater to keep the water at 55 for my shower! I won't need to buy a water heater for the monsoon season!
Great Idea! The plumbing is exposed in the ceiling of my basement. I could drop one of the copper water pipes down to the amp level and pop the transistors right onto that! 
Getting the box welded will cost me more than buying a heatsink so I bought a heatsink last night. The computer cooling systems cost ALOT and I was thinking of doing this just to save money. Ended up with this sink:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200231372424&ssPageName=ADME:B:EOIBSA:US:1123
I would like to be able to saw it in half to use the amps as monoblocks. Will give it a shot, but I dont think it is going to be easy. Probably have to just mount both amps to the single sink.
Uriah
Getting the box welded will cost me more than buying a heatsink so I bought a heatsink last night. The computer cooling systems cost ALOT and I was thinking of doing this just to save money. Ended up with this sink:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200231372424&ssPageName=ADME:B:EOIBSA:US:1123
I would like to be able to saw it in half to use the amps as monoblocks. Will give it a shot, but I dont think it is going to be easy. Probably have to just mount both amps to the single sink.
Uriah
My guess, and its a guess, is that it will support the whole amp in stereo. Like I said I might try to cut it, but have never tried to cut thick aluminum before. People say you can do it on a table saw, but everytime I think about it I picture shards of saw blade flying about at Mach2.
Uriah
Uriah
Cuttting Heatsinks
To cut metal on a table-saw or other circular saw, use the black-gray narrow grindstone looking things available at HD called non-ferrous metal cutting blades.
I have done it. The heatsink being cut will get hot, and some chards will shoot from it. No sparks like steel. Will probably pop a fuse or two if your two aggressive with it.
To cut metal on a table-saw or other circular saw, use the black-gray narrow grindstone looking things available at HD called non-ferrous metal cutting blades.
I have done it. The heatsink being cut will get hot, and some chards will shoot from it. No sparks like steel. Will probably pop a fuse or two if your two aggressive with it.
JFETs and heat sinks
Hello Group
I wrote a few comments on my experience with working with aluminium on the Conrad heat sink thread if you are interested.
Right now am trying to aquire JFETS for building this and other NP designed prjects. Can any body help me out here with a supplier or share some or anything.
Thanks for the help
Hello Group
I wrote a few comments on my experience with working with aluminium on the Conrad heat sink thread if you are interested.
Right now am trying to aquire JFETS for building this and other NP designed prjects. Can any body help me out here with a supplier or share some or anything.
Thanks for the help
To cut metal on a table-saw
To cut metal on a table-saw I've used a Freud LU89M010 10 inch blade
with 72 teeth. Ordered from Ace Tool Repair, Wantagh, NY. { seach the net for best buy}.
I've cut 1/8", 1/4" and 3/4" with no problem. Just make sure your table is
surper aligned. Cann't use spackle to hide bad joints etc.
See http://www.diyaudio.com/forums/showthread.php?s=&threadid=3981&perpage=25&highlight=&pagenumber=1
...under diyAudio Forums > Top >Other Stuff >Everything Else >Useful tools and techniques
for lots of tips.
To cut metal on a table-saw I've used a Freud LU89M010 10 inch blade
with 72 teeth. Ordered from Ace Tool Repair, Wantagh, NY. { seach the net for best buy}.
I've cut 1/8", 1/4" and 3/4" with no problem. Just make sure your table is
surper aligned. Cann't use spackle to hide bad joints etc.
See http://www.diyaudio.com/forums/showthread.php?s=&threadid=3981&perpage=25&highlight=&pagenumber=1
...under diyAudio Forums > Top >Other Stuff >Everything Else >Useful tools and techniques
for lots of tips.
Re: To cut metal on a table-saw
Thanks man. This is a great link for way more than just cutting metal Will get the right blade now. Thanks again,
Uriah
ichiban said:To cut metal on a table-saw I've used a Freud LU89M010 10 inch blade
with 72 teeth. Ordered from Ace Tool Repair, Wantagh, NY. { seach the net for best buy}.
I've cut 1/8", 1/4" and 3/4" with no problem. Just make sure your table is
surper aligned. Cann't use spackle to hide bad joints etc.
See http://www.diyaudio.com/forums/showthread.php?s=&threadid=3981&perpage=25&highlight=&pagenumber=1
...under diyAudio Forums > Top >Other Stuff >Everything Else >Useful tools and techniques
for lots of tips.
Thanks man. This is a great link for way more than just cutting metal
Will get the right blade now. Thanks again,Uriah
F5 Compensated Prototype:
An externally hosted image should be here but it was not working when we last tested it.
fredlock said:
I had some prototype boards made -- I don't have the facilities to do plated through-holes and vias. I usually try to make my own boards for prototypes, but haven't had the time.
The holes for the source resistors plated up a bit heavier than I wanted so I had to dremel them out to 41 mils. On the photo I used the Ohmite TWW's which are like little radiators. The board house did a sloppy job of snapping the grid, they ignored the board outline, so I had to cut them down on my contractor saw. (It was probably my error as I had a "hole" on the gerber which I failed to pick up.)
Nice and warm and stable -- the other F5's I had built didn't have the thermal compensation -- this has been very stable with the thermistors just adjacent to the output devices (i.e. not glued on):
An externally hosted image should be here but it was not working when we last tested it.
The 2 balanced prototypes I built did not have thermal compensation.
At cold start, the bias was around 3.5A. After 1 hours (steady state), heatsink temperature went to 50 degC, and the bias rose to its proper working level of 4A.
As far as I am concerned, I am not going to be bothered with thermistors.
Patrick
At cold start, the bias was around 3.5A. After 1 hours (steady state), heatsink temperature went to 50 degC, and the bias rose to its proper working level of 4A.
As far as I am concerned, I am not going to be bothered with thermistors.
Patrick
Hello ,
here 's my first F5 , builded as p2p little boards .
I didnt use the thermistor too and actually felt to replace R15 and TH1 ( same for R16 and TH2 ) by a 5,7 K ohm resistor to have similar gain .
The amp itself was very easy to set to proper operating values , I preferred to turn on the Nchannel mosfet first anyway ( dont ask me why ) .
It is all working ok AFAIK and guess the heat sinks stays at about 50 degrees , I can touch them for 5-6 seconds or so .
The capacitor bank are 2 *56000uF par rail filtered with 0.22ohm . So after a little playing with the ground the amp is very very quiet at the speakers . There is the Earth connection through a CL60 .
here 's my first F5 , builded as p2p little boards .
I didnt use the thermistor too and actually felt to replace R15 and TH1 ( same for R16 and TH2 ) by a 5,7 K ohm resistor to have similar gain .
The amp itself was very easy to set to proper operating values , I preferred to turn on the Nchannel mosfet first anyway ( dont ask me why ) .
It is all working ok AFAIK and guess the heat sinks stays at about 50 degrees , I can touch them for 5-6 seconds or so .
The capacitor bank are 2 *56000uF par rail filtered with 0.22ohm . So after a little playing with the ground the amp is very very quiet at the speakers . There is the Earth connection through a CL60 .
Attachments
stefanobilliani said:Oh the last picture shows how the complete will look like
and cant forget to say that I liked it pretty soon , was actually very involved in listening the system with a pair of Jordans in MLTL .
It is doing a nice JOB
few long slots on upper plate , same as on bottom plate , oriented as you like ........
and you can call it Woodie
( and I can call it fugly!
)