if you want them all ,pcbs and critical parts matched and in one package , rest available in nearest grocery store , then here goes shameful plug
Well, that helps....
Well, that helps....
Hi VictoriaGuy,
The babelfish kit mentioned is ZM's take on an aleph with jfet input:
http://www.diyaudio.com/forums/pass-labs/273318-about-possible-babelfish-j-interest.html
http://www.diyaudio.com/forums/swap-meet/273336-babelfish-j-package.html#post4301409
(Orig thread on the babelfish-j here:
http://www.diyaudio.com/forums/pass-labs/75281-babbelfish-j-pcbs.html )
Cheers,
Dennis
I believe that would be a pretty comfortable budget for one...probably
$800 - $900 is possible.
Most of the cost of building one is the hardware of the chassis, and
the power supply (transformer and caps).
Dennis
My suggestion in other threads has been to build a stand alone multi-use power supply which will power virtually any Pass amp clone. [If you foresee a need for a dual mono supply, you can always insert a second circuit at a later date thereby saving money on a second enclosure. Being old now I feel that this is the way to go]. This is - initally - more expensive but any subsequent amp can be built later at a big saving.
You can build monobloc amps - light enough to haul around by yourself! Naturally if you can see your build being a "one off" effort, then choose whatever option most suits your needs and budget.
Regarding the cost of rare out of production devices...ZM recently made the point that yes they are expensive, but when compared with matched tubes they are not such a bad deal!
I am finishing up my Aleph J build and I kept a spreadsheet of components and the cost. For parts alone for the amp and the power supply for me it was $473.45 This included the boards and transistor kits from the DIY store and also a better pair of caps. The enclosure, hardware and connections will depend on if you buy an enclosure or make one. So that cost could be anywhere from $350 to $500 or more. I am making my own enclosure and my cost right now is sitting at $794.33 for the amp. This does not include metric hardware. I have not put that into the spreadsheet yet.
You may be correct!Regarding the cost of rare out of production devices...ZM recently made the point that yes they are expensive, but when compared with matched tubes they are not such a bad deal!
However, I generally don't build tube amps that need 'no longer made' /'crazy priced NOS tubes' as I want them to be usable/maintainable in the future. Most likely all my builds will end up in the landfill when I'm dead, but the alternative scenario (treasured by future generations) is a comforting fantasy.
I was brainwashed in the 70s to think of SS devices as 'lasting forever' - apparently that's not the case. I also read a lot of 'I smoked the transistors' in the SS build and repair threads.
I've done some stupid things in building, but I haven't destroyed a tube yet (damaged, perhaps, but not destroyed!
). It sounds like it's quite easy to destroy SS devices or have the amp 'run away'.....
So I hesitate to build with devices that can't be replaced.
It's part of my general philosophy "Never buy a car if the parts aren't available at the local auto supply store!"
Thanks for the comments and feedback from my questions.
Thanks to all who have been patient with my questions.
As a complete newcomer to the 'build from scratch' style of SS amp , I find it quite confusing to negotiate through the maze....
(I've built some chip amps from PCBs and a bunch of tube stuff 'from scratch' P2P.)
For the Pass amps, it would be extremely helpful if there were a table/spreadsheet showing the various DIY designs, intended function (what's all this voltage amp VS current amp stuff??), parts availablilty, and cost. I really don't want to read 15 000 posts and then find out that the parts are unobtainable!
For instance, it sounds like all these Class A designs require extremely expensive and large heatsinks, even though some are 'low powered' - it's very confusing for an 'outsider'. There doesn't seem to be an easy way to figure out if heatsinks from the scrap box will do the job, and the price of a miscalculation is destroying expensive 'matched' SS devices.
As a complete newcomer to the 'build from scratch' style of SS amp , I find it quite confusing to negotiate through the maze....
(I've built some chip amps from PCBs and a bunch of tube stuff 'from scratch' P2P.)
For the Pass amps, it would be extremely helpful if there were a table/spreadsheet showing the various DIY designs, intended function (what's all this voltage amp VS current amp stuff??), parts availablilty, and cost. I really don't want to read 15 000 posts and then find out that the parts are unobtainable!
For instance, it sounds like all these Class A designs require extremely expensive and large heatsinks, even though some are 'low powered' - it's very confusing for an 'outsider'. There doesn't seem to be an easy way to figure out if heatsinks from the scrap box will do the job, and the price of a miscalculation is destroying expensive 'matched' SS devices.
I guess if it were easy (and inexpensive) then everyone would do it but several times I've poured through threads on builds thinking 'this will be my next project' only to get derailed trying to figure out which parts are still available and which can be replaced with what. Or the 'I used old, not available power supply PCBs but you can make do with something else' parts to the build thread. Um, no I can't, not yet at least. I need to copy what you did and then maybe understand what it is doing and be able to tweak it later if necessary.
The other problem I run into is I know just enough to get myself in trouble but not enough to understand many of the posts on how to get back out of trouble with the build.
As a stranger in Electronicsville I'm only slightly familiar with the language and as helpful as many of the residents try to be the language is often way above my head. Sometimes they might as well be shouting "oogly boogly! oogly boogly!" for all of my understanding ability.
As I go through the threads I keep muttering to myself "give me a parts list, give me a parts list for exactly what you are building (and have it be currently available parts)" only to find partial lists with some parts as 'optional' or 'figure out the value based off your other components' and have seen people chastised for asking for a BOM because "Just make a list off the schematic".
As expensive as some of the components are I really want to know up front that I've sourced every part needed before ordering anything.
Having built a point to point single ended tube amp from nothing more than a schematic that sounds really good and then the Amp Camp Amp with the PCBs and sourcing all the parts for it my confidence shot up. Probably higher than it should have been.
I spent a long time shopping for heatsinks for the ACA only to find recently that if I'd drilled down deeper in the menus at the store here they were available separate from the kit (undrilled but still available).
What makes these projects so much fun is everyone innovates, tweaks and changes their build a bit from the prior one; often using some old parts they already had.. But that makes it really difficult for the non-engineer to 'copy'.
Maybe it isn't true DIY then, but I would love a next step up from the ACA that would have PCBs and a tested and proven BOM (with good heatsink specs) that would go together and function well with minimal adjustments like the ACA.
These amplifiers use the same PSU:
Local voltage primary
18V+18V x 300VA secondary
2 x 35A bridge rectifiers or equivalent discrete diodes
CRC: 30mF + 0.1R 12W + 30mF + 2K2 bleeder per rail
They also require between 5lb and 6lb (2.3Kg to 2.7Kg) of reasonably designed heat sink per side (L + R)
border="1"
|-
| class="tcat" | Amplifier
| class="tcat" | Input stage
| class="tcat" | Output stage
|-
| Aleph J || 2SJ74 + 2SJ74 || 3 x IRFP240 + 3 x IRFP9240
|-
| F4 || 2SK170 + 2SJ74 || 3 x IRFP240 + 3 x IRFP9240
|-
| F5 || 2SK170 + 2SJ74 || 1 x IRFP240 + 1 x IRFP9240
|-
| F6* || 2SK170 + 2SJ74 || 2 x IRFP240
|-
| M2* || 2SK170 + 2SJ74 || 1 x IRFP240 + 1 x IRFP9240
|-
| BA-3 || 2SK170 + 2SJ74 || 3 x IRFP240 + 3 x IRFP9240 or 6 x IRFP240
|-
(*) F6 and M2 also require input transformers, which are in current production
2SK170 and 2SJ74 can be replaced by LSK170 and LSJ74 respectively, which are in current production
PCBs are available from the DIYAudioStore, except M2's which I still have a few left from a group buy and Tea-Bag also has available
This summary should help those trying to make sense of Nelson Pass's designs available to the community. Whatever is missing, Papa's little helper (Zen Mod) will certainly add later on.
Local voltage primary
18V+18V x 300VA secondary
2 x 35A bridge rectifiers or equivalent discrete diodes
CRC: 30mF + 0.1R 12W + 30mF + 2K2 bleeder per rail
They also require between 5lb and 6lb (2.3Kg to 2.7Kg) of reasonably designed heat sink per side (L + R)
|-
| class="tcat" | Amplifier
| class="tcat" | Input stage
| class="tcat" | Output stage
|-
| Aleph J || 2SJ74 + 2SJ74 || 3 x IRFP240 + 3 x IRFP9240
|-
| F4 || 2SK170 + 2SJ74 || 3 x IRFP240 + 3 x IRFP9240
|-
| F5 || 2SK170 + 2SJ74 || 1 x IRFP240 + 1 x IRFP9240
|-
| F6* || 2SK170 + 2SJ74 || 2 x IRFP240
|-
| M2* || 2SK170 + 2SJ74 || 1 x IRFP240 + 1 x IRFP9240
|-
| BA-3 || 2SK170 + 2SJ74 || 3 x IRFP240 + 3 x IRFP9240 or 6 x IRFP240
|-
2SK170 and 2SJ74 can be replaced by LSK170 and LSJ74 respectively, which are in current production
PCBs are available from the DIYAudioStore, except M2's which I still have a few left from a group buy and Tea-Bag also has available
This summary should help those trying to make sense of Nelson Pass's designs available to the community. Whatever is missing, Papa's little helper (Zen Mod) will certainly add later on.
As someone solidly in the "oogly boogly! oogly boogly!" camp. I just want to echo the comments of recent posters asking for more (sounds like Oliver Twist; 'Please sir..').
The combination of Mr Pass's design and the forums' complete ACA kit not only addresses the simplicity, but also gives the ability to finish without getting hooked up on a detail that requires a lot more understanding. This is the difference between people who go on and people who sit on the side. There is some cost increase in going up to the other models, but I suspect that is not the whole story and perhaps the testing and setup is much more complex(?).
I also am hesitant to invest the money in the ACA when I know for some incremental amount I can get a top of the line amplifier. So for example, is there a way to step from one to the next without starting from scratch? The recent post on building a separate PSU and then adding standalone amplifiers seems a good way to start.
regardless, many thanks for all the illumination and information on these posts.
Beardy
The combination of Mr Pass's design and the forums' complete ACA kit not only addresses the simplicity, but also gives the ability to finish without getting hooked up on a detail that requires a lot more understanding. This is the difference between people who go on and people who sit on the side. There is some cost increase in going up to the other models, but I suspect that is not the whole story and perhaps the testing and setup is much more complex(?).
I also am hesitant to invest the money in the ACA when I know for some incremental amount I can get a top of the line amplifier. So for example, is there a way to step from one to the next without starting from scratch? The recent post on building a separate PSU and then adding standalone amplifiers seems a good way to start.
regardless, many thanks for all the illumination and information on these posts.
Beardy
I think this point bears repeating: With the availability of the LSK170/LSJ74,
all parts (or functional equivalents) in the F4, F5, F6, M2, Aleph-J are
in production; no hunting for unobtainiums needed.
Cheers,
Dennis
I noticed a mistake in the Aleph J Output stage. Here is the table corrected and enhanced.
border="1"
|-
| class="tcat" | Amplifier
| class="tcat" | Input stage
| class="tcat" | Output stage
|-
| Aleph J || 2SJ74 + 2SJ74 || 2 x IRFP240 (matched) + 2 x IRFP240 (matched)
|-
| F4 || 2SK170 + 2SJ74 || 3 x IRFP240 (matched) + 3 x IRFP9240 (matched)
|-
| F5 || 2SK170 + 2SJ74 || 1 x IRFP240 + 1 x IRFP9240
|-
| F6* || 2SK170 + 2SJ74 || 2 x IRFP240
|-
| M2* || 2SK170 + 2SJ74 || 1 x IRFP240 + 1 x IRFP9240
|-
| BA-3 || 2SK170 + 2SJ74 || 3 x IRFP240 (matched) + 3 x IRFP9240 (matched) or 6 x IRFP240 (matched)
|-
|-
| class="tcat" | Amplifier
| class="tcat" | Input stage
| class="tcat" | Output stage
|-
| Aleph J || 2SJ74 + 2SJ74 || 2 x IRFP240 (matched) + 2 x IRFP240 (matched)
|-
| F4 || 2SK170 + 2SJ74 || 3 x IRFP240 (matched) + 3 x IRFP9240 (matched)
|-
| F5 || 2SK170 + 2SJ74 || 1 x IRFP240 + 1 x IRFP9240
|-
| F6* || 2SK170 + 2SJ74 || 2 x IRFP240
|-
| M2* || 2SK170 + 2SJ74 || 1 x IRFP240 + 1 x IRFP9240
|-
| BA-3 || 2SK170 + 2SJ74 || 3 x IRFP240 (matched) + 3 x IRFP9240 (matched) or 6 x IRFP240 (matched)
|-
Is the power (dissipated as heat and output to speakers) proportional to the number of output devices?
i.e. is the same capacity power supply and same hefty heat$ink$ required for all the designs? It would seem 'not' to me, but everything I read seems to indicate that the same PS and sinks are used in all those designs...
I'd think that the F5,F6, and M2 would have more modest requirements but none of my 'tube thinking' seems to apply here!!
i.e. is the same capacity power supply and same hefty heat$ink$ required for all the designs? It would seem 'not' to me, but everything I read seems to indicate that the same PS and sinks are used in all those designs...
I'd think that the F5,F6, and M2 would have more modest requirements but none of my 'tube thinking' seems to apply here!!
The Aleph J, F4 and BA-3 use output devices in parallel so they are able to handle together more current. These amplifiers require more heat sink capacity than the F5, F6 and M2. However, not a lot more. So, for a manufacturer like First Watt, it is more cost effective to have a case and PSU which can be used for every design. A large number of members building the clones purchase their cases from the DIYAudio store which offers models suitable to use with the PCBs they also sell. That's why you keep seeing the same cases and PSUs used time and again. Follow the link for pictures of an M2 clone using hand crafted case and dual, compact, PSU boards.
http://www.diyaudio.com/forums/pass-labs/166784-pictures-your-diy-pass-amplifier-155.html#post4980497
http://www.diyaudio.com/forums/pass-labs/166784-pictures-your-diy-pass-amplifier-155.html#post4980497
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Which of the chassis sold in the store are good 'enough' for the M2? Will the 300mm Dissipante 4U work?
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