never tryed it. but its hard to get a nice thin coat betwin the fins. powder coat is easy that way.
high temp paint also have to be baked in a owen. or it just falls off.
I'm going to see how much the par metal ones are at 8" long. At least they're anodized. And I actually think the fin spacing is ok despite being better suited for forced air. The benefit of additional surface area will offset that to some degree as well. Also, I may just end up adding some sort of fan base anyway. The pros out weigh the cons more easily given the high proportionate cost of heat sinks in this build. That said, perhaps I'll just go with the stock 5" heat sinks if the fan base becomes more of a likelihood in my mind.
Also, can I use wirewound resistors for the 5W 1R resistors? Maybe this one.
It will be a tight fit on my board width wise but I stagger them top to bottom.
Otherwise, I can get these metal oxide ones. They're a little long though.
It will be a tight fit on my board width wise but I stagger them top to bottom.
Otherwise, I can get these metal oxide ones. They're a little long though.
After some research, I think the fin spacing is ok. The table claims minimum fin spacing of 6.5mm for 75mm long fins. The par-metal sinks I want are spaced at 7.1mm and the fins are only 48mm long.
Separate question... anyone have source for matched IRF9610s? I think I just need 2 pairs matched. The third one doesn't have to match, right?
Separate question... anyone have source for matched IRF9610s? I think I just need 2 pairs matched. The third one doesn't have to match, right?
Looks like some BOMs use the BC550C instead of the 2SC2240. I couldn't find any rationale or pros/cons though. Is the BC550C ok? I think I have a ton of these lying around from some of my Amb headphone amp projects.
you can also use BC546.
just use what suits you. just be watch the leg posisions
i use BC546 for my aleph2's and aleph30
Cool... I think I have some of those lying around too!
Turns out I have plenty of 550's to choose from. I think I have the B's and the C's actually. My understanding is the C's would be preferable due to higher hfe?
Looks like the pins are indeed different from the 2SC2240. Might be a little tricky since it's not backwards... it's 3,1,2 so two pins would cross. Will have to be careful not to short them.
Looks like the pins are indeed different from the 2SC2240. Might be a little tricky since it's not backwards... it's 3,1,2 so two pins would cross. Will have to be careful not to short them.
I love your projects. You do beautiful work.
If you still need the input MOSFET's (when you say Aleph X I'm assuming you mean the original with the MOSFET diff pair input version) I would be happy to send you two matched pairs of Intersil IRF9510's free - no charge. They are taken from the original boards shown in my amplifiers here:
http://www.diyaudio.com/forums/pass-labs/73543-ax100-100w-aleph-x-monoblocks.html
IMO the 9510's work better here because they have a bit more admittance and the Intersil parts don't have the gain shelf issue that the IR/Vishay parts do either. If you want matched IR 9610's I can do that instead, but you'll have to wait a couple of weeks for me to match them.
I will also send you two irf9610's for the CCS's for the diff pairs.
I converted my amps to JFET front ends years ago. The JFET's sound better.
I have used the AX100J's continuously for the last 5-6 years and I really am happy with them. Recently though, I have been thinking about building a pair of 200W F5T's. It's the first circuit to come down the road in all that time that has tempted me. So I find it fascinating that you are on what I would call the opposite road.
I don't think my PM is enabled. So give me a chance to get that going and you can send me your shipping address. If you're going to the 2012 Burning Amp and are willing to wait I can hand these parts over in person.
Graeme
If you still need the input MOSFET's (when you say Aleph X I'm assuming you mean the original with the MOSFET diff pair input version) I would be happy to send you two matched pairs of Intersil IRF9510's free - no charge. They are taken from the original boards shown in my amplifiers here:
http://www.diyaudio.com/forums/pass-labs/73543-ax100-100w-aleph-x-monoblocks.html
IMO the 9510's work better here because they have a bit more admittance and the Intersil parts don't have the gain shelf issue that the IR/Vishay parts do either. If you want matched IR 9610's I can do that instead, but you'll have to wait a couple of weeks for me to match them.
I will also send you two irf9610's for the CCS's for the diff pairs.
I converted my amps to JFET front ends years ago. The JFET's sound better.
I have used the AX100J's continuously for the last 5-6 years and I really am happy with them. Recently though, I have been thinking about building a pair of 200W F5T's. It's the first circuit to come down the road in all that time that has tempted me. So I find it fascinating that you are on what I would call the opposite road.
I don't think my PM is enabled. So give me a chance to get that going and you can send me your shipping address. If you're going to the 2012 Burning Amp and are willing to wait I can hand these parts over in person.
Graeme
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Wow, thanks Graeme! For both the compliments as well as the offer for parts. My projects are done as cheaply as I can without being entirely embarrassing to show in public. It's a delicate balance. Plus, they probably look worse in person once you get close.
Your Alephs are pretty awesome though! I love the exposed parts and heat sink design.
A couple pairs of 9510's with 9610's for the CCS would be awesome! I actually have some spare JFETs (2SK170BL and 2SJ74BL) lying around so maybe I'll do some research there to see if I should pre-emptively make the "upgrade." My guess is I'll go with the standard build for now though since I have all the parts for that already. As such, I'll look for your PM and get you my address. Thanks again!
Will hopefully see you at burning amp!
Your Alephs are pretty awesome though! I love the exposed parts and heat sink design.
A couple pairs of 9510's with 9610's for the CCS would be awesome! I actually have some spare JFETs (2SK170BL and 2SJ74BL) lying around so maybe I'll do some research there to see if I should pre-emptively make the "upgrade." My guess is I'll go with the standard build for now though since I have all the parts for that already. As such, I'll look for your PM and get you my address. Thanks again!
Will hopefully see you at burning amp!
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