Another pic...
On the temp I tried to use Williams X Aleph spread sheet and scaled the bias accordingly.
The good news its still alive!
The boards are Mark Finnis Aleph 5 and I fabricated a small daughter board for the 109's.
The Master said I should move on from the X Aleph so here we are.
There is an interesting story to this project.
I little while ago a friend in Brooklyn asked me what would I recommend a as diy project for biamping his horn system..he uses Light Force amps on his Altec woofers, I suggested the Aleph J.
Initally I was going to help with the boards and a few parts because I had some of the Jfets. When I got started I enjoyed it so much I thought I may as well assemble it and one thing lead to another. (I do this for fun only)
The hard part as always is the chassis. So we decided to make the amp as modules around the heatsinks that would form the basis for the chassis.
Conrad make some of the best heatsinks so I called Julian and went from there (its quite interesting to tour through the factory)
I used L angle and some square 12mm rod & flat bar stock and extended the angle an inch proud of each end of the 300mm heatsinks. All the hardware is M4 and M3 stainless steel except for the flanges so metric Allen keys want be a problem in NY trying to assemble it!
I will bark it up tomorrow night but this will be a good excuse to stop over in NY and see how it all turned out next time I fly over the Big Pond.
Ian
On the temp I tried to use Williams X Aleph spread sheet and scaled the bias accordingly.
The good news its still alive!
The boards are Mark Finnis Aleph 5 and I fabricated a small daughter board for the 109's.
The Master said I should move on from the X Aleph so here we are.
There is an interesting story to this project.
I little while ago a friend in Brooklyn asked me what would I recommend a as diy project for biamping his horn system..he uses Light Force amps on his Altec woofers, I suggested the Aleph J.
Initally I was going to help with the boards and a few parts because I had some of the Jfets. When I got started I enjoyed it so much I thought I may as well assemble it and one thing lead to another. (I do this for fun only)
The hard part as always is the chassis. So we decided to make the amp as modules around the heatsinks that would form the basis for the chassis.
Conrad make some of the best heatsinks so I called Julian and went from there (its quite interesting to tour through the factory)
I used L angle and some square 12mm rod & flat bar stock and extended the angle an inch proud of each end of the 300mm heatsinks. All the hardware is M4 and M3 stainless steel except for the flanges so metric Allen keys want be a problem in NY trying to assemble it!
I will bark it up tomorrow night but this will be a good excuse to stop over in NY and see how it all turned out next time I fly over the Big Pond.
Ian
Attachments
A question about heatsinks for Aleph J?
My german friend wants to use a case/heatsink set and the catalog states that the Heat transger value of the heatsinks (mounted in the case) are approx. 0,3 C/W but the values of each heatsink (free, not mounted) are 0,15 C/W.
Two times better than mounted in a case?
Can he still use the mounted Heatsinks for the Aleph J (2x250VA Transformator and with 4 IRFP240 per Heat sink)?
2 heatsink with size 300mm x 150mm x 80mm!
My german friend wants to use a case/heatsink set and the catalog states that the Heat transger value of the heatsinks (mounted in the case) are approx. 0,3 C/W but the values of each heatsink (free, not mounted) are 0,15 C/W.
Two times better than mounted in a case?
Can he still use the mounted Heatsinks for the Aleph J (2x250VA Transformator and with 4 IRFP240 per Heat sink)?
2 heatsink with size 300mm x 150mm x 80mm!
DVBjunky said:
if these heatsinks should be mounted in normal way - fins in free air , they'll be certainly more than adequate ;
tell him that he worry too much .......
jacco vermeulen said:
yup .......
world is small ....... besides cwayzee serbie and cwayzee dutchie, seems that we have few cwayzee deutshie here ......
Yeah!
Aykman is a pal of mine. We did talk about heatsinks and the several formulas (or online tools) to calculate heat issue.
My 2cents are - it doesnt matter.....the case will work because with the KL-271 from seifert they have approx. 50-55 Celsius....and so Aykman willl have 60-65 Celsius! But I want to be safe and asked
- >> He will joins us...as soon he reactivated his account.
@ jacco
Are you also a regular member at the AAA Forum?
regards
Alan
Aykman is a pal of mine. We did talk about heatsinks and the several formulas (or online tools) to calculate heat issue.
My 2cents are - it doesnt matter.....the case will work because with the KL-271 from seifert they have approx. 50-55 Celsius....and so Aykman willl have 60-65 Celsius! But I want to be safe and asked
- >> He will joins us...as soon he reactivated his account.
@ jacco
Are you also a regular member at the AAA Forum?
regards
Alan
Zee-Mee, Stop following me around the block.
Moderators : Help, Harassment !!
Aah, that was fun, i feel much better now, thank you.
Very relaxing, better than 2 hours of beating up a bag at the gym, even the live ones.
Anyway, the heatsinks of the HF2K boxes are similar to Fischer's SK-56.
The 0.30C/W (0.31) checks out and is for 1 heatsink, which makes 0.15C/W for 2 heatsinks combined.
If the temperature still turns out too high there are some tricks to lower it, either through decreasing the dissipation by biasing to a lower quiescent current level, or by lowering the total C/W value.
One way for that would be to improve the thermal transfer contact between the heatsinks and the chassis.
A second rescue option would to place the power amp on a nice piece of rock, with some room between them, and thermally connect the two.
Something Brinkmann has been doing with his sleek open view Mono amp model for Gawd knows how long.
( Ja doch, sogar mit dem AJ Platinchen Gruppeneinkauf und den ganzen Kram.
)
Moderators : Help, Harassment !!
Aah, that was fun, i feel much better now, thank you.
Very relaxing, better than 2 hours of beating up a bag at the gym, even the live ones.
Anyway, the heatsinks of the HF2K boxes are similar to Fischer's SK-56.
The 0.30C/W (0.31) checks out and is for 1 heatsink, which makes 0.15C/W for 2 heatsinks combined.
If the temperature still turns out too high there are some tricks to lower it, either through decreasing the dissipation by biasing to a lower quiescent current level, or by lowering the total C/W value.
One way for that would be to improve the thermal transfer contact between the heatsinks and the chassis.
A second rescue option would to place the power amp on a nice piece of rock, with some room between them, and thermally connect the two.
Something Brinkmann has been doing with his sleek open view Mono amp model for Gawd knows how long.
( Ja doch, sogar mit dem AJ Platinchen Gruppeneinkauf und den ganzen Kram.
)
Hmm, what was it again ?
Oh yeah, if both the feet and granite have a very smooth surface, the weight of the power amp enables a moderate thermal resistance between both. =>Class AB ampy, kemo sabe Bwana ?
Drilling some holes in the tomb stone to shove a couple of bolts through , plus a dab of the familiar sun tan cream, would be smarter cookie for a Class A critter.
Last time i saw this amp in the nude was like 2 decades ago, pretty amazing l-t-c stretch for an audio product.
Oh yeah, if both the feet and granite have a very smooth surface, the weight of the power amp enables a moderate thermal resistance between both. =>Class AB ampy, kemo sabe Bwana ?
Drilling some holes in the tomb stone to shove a couple of bolts through , plus a dab of the familiar sun tan cream, would be smarter cookie for a Class A critter.
Last time i saw this amp in the nude was like 2 decades ago, pretty amazing l-t-c stretch for an audio product.
Attachments
jacco vermeulen said:
Jacco san, do you mean without leaving some space between bottom plate of amp and tombstone for airflow?
Ou j'ai mal comprendo , comme d'hab.?
But if it works, that with the stone, I will give a try.
May be can ZM provide some old oily BQ
serbian stone for this purpose. As a bonus would be the smell of burned cevapis everytime I play music.
Hang on, just how many of those "habitudes" have you got ?
No, there has to be a gap for airflow, which large round metal feet clear.
Stuff like granite or marble does not replace aluminium heatsinks, but it's a nice aesthetic emergency add-on.
(Excuser for the late reply, my belly was in need of grilled tuna steak at the sea front. My favorite place around the corner, i can even check at home to see if it's rush hour before heading over: 1984-1 + 1984-2 . Plus they have insane club and beach parties, me dansa the night away)
No, there has to be a gap for airflow, which large round metal feet clear.
Stuff like granite or marble does not replace aluminium heatsinks, but it's a nice aesthetic emergency add-on.
(Excuser for the late reply, my belly was in need of grilled tuna steak at the sea front. My favorite place around the corner, i can even check at home to see if it's rush hour before heading over: 1984-1 + 1984-2 . Plus they have insane club and beach parties, me dansa the night away)
