deep breath^ Thanks so much! I'll keep digging around. I was aware of the need for proper sinking, and I hope I've taken care of that. What I was looking for more information around was your comment that you thought "sustained heat will kill them over time" specifically when compared to something like a 240. I know dissipating the heat due to the small(er) package might be a concern, but I'm more interested in operating temperatures of concern over time. Like, how high is too high over time? As an example, I have no concern with running 240s at what I'd assume generally to be 75C+ junction temps for the life of my amps, but if I should not run the 1014Ds at those types of temps, I'd very much like to know.
I'd be grateful for any other information from all sources. Sorry for a bit OT.
Edited to correct - package to junction... key difference. My package temps are generally no higher than 60C.
Ok. I killed* my F3, which had, in it's original incarnation, LU1014Ds soldered directly to PCBs with a dumb little hollow brass cube mounted underneath the PCB, soldered to the vias, which was conducting the heat from the LU1014D to the heat sink through a piece of keratherm. Now there were a lot of suspects in the death of my F3, but I suspect heat the most because I could routinely measure case temps via heat gun that were north of 60C, and the immediate external portion of the heat sinks nearest that area of the board were frequently too hot to touch for long. I'd point you to the F3 builder's thread for that saga. This is anecdote! YMMV!
*killed here is defined as a noticeably narrow and distorted sound when played through 2-way speakers with a weird series crossover, which probably present a reactive load that the F3 topology doesn't like. This was followed by distortion analysis at BAF2022 which revealed utter horrors into a 4 ohm load.
A comment here, the 3U heat sink isn't large enough to accomodate the full UMS drill hole pattern, and if you ask Modushop to drill the UMS pattern for you on a 3U 300 heat sink, they won't do it. It can fit the subset necessary to mount @rhthatcher 's Aleph 30/40 boards, however, which can be drilled by hand.
I have dxf and fpd files for the pattern I used to mark the sinks for drilling that are shown below, it's basically a redacted version of the UMS pattern. The files can't be attached, but are available on request.
Attachments
I spoke with @Gianluca. He mentioned that with ranshdow's drawing, he can drill the 3U 300mm heatsinks for the Aleph boards. Otherwise, the UMS pattern will fit onto the 3U 400mm chassis.
With the 3U 400mm chassis, all you have to do is purchase the chassis and the service to drill the heatsinks.
With the 3U 400mm chassis, all you have to do is purchase the chassis and the service to drill the heatsinks.
Also be sure the partial pattern is centered vertically on the 3U heatsink. The standard UMS pattern is 40mm up from the bottom edge of a 4U heat sink, it needs to be re-centered for a 3U.
Hi. I have commenced my A2 build with the 3 trimpot installation. What is the correct value for R16 392 ohms Version 1.0d or 150 ohms as per the original Old School Aleph 2 Schematic. Thanks.
See the section in the build doc about trimpots. There should be a table showing fixed resistor + initial pot setting value = tots target that is equal to original a2 fixed resistor.
Sorry I might be missing the point. R16 is not a component in the trimpots list. It sits on the base of Q4 to the negative rail. Thanks again
R16 is 150R for aleph 2. When in doubt, refer to the BOM.
The BOM adapts the old school schematic to the new boards.
The BOM adapts the old school schematic to the new boards.
I have a modest amount of experience in this area. I suspect Pa suggested 100Hz because he knows some multimeters cannot accurately measure voltage at frequencies much past 60Hz. I followed his previous recommendations and bought the following for basic tasks. Multimeter . Fortunately for me I have a number of Flukes that are good from 60-1000Hz when measuring AC voltages. You have to check your meters specifications or you won't get accurate readings.
Regards,
Dan
The cheap meters were great when I was setting up my VFET2 and had six meters going at once. In my experience Flukes are one of the best but don't fit everyone's budget.
Regards,
Dan
Regards,
Dan
After building a single chassis full power schade as seen here 50w Single-Ended BAF2015 Schade Enabled I discovered a really good reason I won't be building an Aleph 1.2. My Single-Ended Schade weighs in at about 110lbs and takes two people to move. Can the lovely 1.2 be a back breaker too?
🤣
Regards,
Dan
I made a tweak to the Aleph 60 Build Notes. It's updated in Post #1 of this thread.
NOW REV V1.0F (29 Feb 2023)
Updated schematic for A60 specific values
Added cleaner "old school" schematic.
Replaced some caps in the BOM (Silmic 2 for Panasonic FC and some out of stock PSU caps with in-stock PSU caps)
NOW REV V1.0F (29 Feb 2023)
Updated schematic for A60 specific values
Added cleaner "old school" schematic.
Replaced some caps in the BOM (Silmic 2 for Panasonic FC and some out of stock PSU caps with in-stock PSU caps)
Nice, thorough work!
The A60 monoblocks I built last spring continue to amaze. I'll build something new, love it, then plug the A60s back in and it's "Welcome home, dear. Here's your martini."
The A60 monoblocks I built last spring continue to amaze. I'll build something new, love it, then plug the A60s back in and it's "Welcome home, dear. Here's your martini."
I know what you mean. I recently finished a Wolverine amp, but I also love the sweet Aleph sound. After years with a HiFi Setup i switched back to where I am coming from: jamaican sound system style. I hooked up a cheap yet good sounding active subwoofer crossover. Now I am using my Aleph 4+4 build with my 2-way loudspeakers and one channel of the dual mono Wolverine for an old 15" Speaker. Sounds great with Reggae and Dub, I feel sorry for my neighbours..
