Yes I agree it is not my preferred layout.
However with this layout it does have the benefit of mounting it vertically (ie directly to the heat sink) so less space is taken up in the case. So you have more room for your transformer and power supply.
I generally like to use heatsinks with the built in bracket for easy mounting of transistors (no need to tap threads) just bolt them down and you are good to go.
However with this layout it does have the benefit of mounting it vertically (ie directly to the heat sink) so less space is taken up in the case. So you have more room for your transformer and power supply.
I generally like to use heatsinks with the built in bracket for easy mounting of transistors (no need to tap threads) just bolt them down and you are good to go.
a) Why not make the PCB ready for an AJ-X ?
b) What pin layout for input diff pair (2SK109) ?
c) How much ? (price and X-Readiness will determine my quantities)
Patrick
PS As you all know, you can still use 2x 2SJ74BLs with the 2SJ109 pin layout.
http://www.diyaudio.com/forums/showthread.php?postid=1690438#post1690438
b) What pin layout for input diff pair (2SK109) ?
c) How much ? (price and X-Readiness will determine my quantities)
Patrick
PS As you all know, you can still use 2x 2SJ74BLs with the 2SJ109 pin layout.
http://www.diyaudio.com/forums/showthread.php?postid=1690438#post1690438
Attachments
> I wonder how many of us would buy the boards if it were the same A30 layout as per pic for the fets ....
> Yes I agree it is not my preferred layout.....
Please kindly explain this to me, as I do not quite understand the problem.
For Class A amps, you always want big heatsinks. The layout show will simply allow you to lay the PCB parallel to a heatsink with a flat (vertical) mounting surface. There are many of those, like the ones from Conrad (though I use something else personally). Just 4 tapped holes, 4 insulators, 4 screws, and it's done.
Or not ?
Patrick
PS Here is an example (my balanced F5) :
http://www.diyaudio.com/forums/attachment.php?s=&postid=1538832&stamp=1213462615
> Yes I agree it is not my preferred layout.....
Please kindly explain this to me, as I do not quite understand the problem.
For Class A amps, you always want big heatsinks. The layout show will simply allow you to lay the PCB parallel to a heatsink with a flat (vertical) mounting surface. There are many of those, like the ones from Conrad (though I use something else personally). Just 4 tapped holes, 4 insulators, 4 screws, and it's done.
Or not ?
Patrick
PS Here is an example (my balanced F5) :
http://www.diyaudio.com/forums/attachment.php?s=&postid=1538832&stamp=1213462615
I generally mount transistors exactly like Nelson does it, and I already have the heat sinks.
If we go with the current layout I will have to buy new heatsinks.
However, maybe it is time I learnt how to tap threads.
By the way we have almost reached the half way point in 5 days.
At this rate we should have the numbers we need within another week.
It looks promising.
I really hope this one goes ahead, as I think this really is a special amplifier. I don't have full range drivers so F1, F2, are out of the question. My speakers are 4 Ohm so F3 is not that great either. I have a B1 preamp so F4 is out of the question.
So it is either Aleph J or F5. I know I love the sound of 2nd harmonic from experience with playing Bass guitar.
So Aleph J I predict will be my favourite (Well F3 will be my favourite for headphones). The only adjustment is for higher bias for 4Ohm load. I think the Aleph 30 or was it 3 (or was it both) was biased to give 60W into 4 ohms.
If we go with the current layout I will have to buy new heatsinks.
However, maybe it is time I learnt how to tap threads.
By the way we have almost reached the half way point in 5 days.
At this rate we should have the numbers we need within another week.
It looks promising.
I really hope this one goes ahead, as I think this really is a special amplifier. I don't have full range drivers so F1, F2, are out of the question. My speakers are 4 Ohm so F3 is not that great either. I have a B1 preamp so F4 is out of the question.
So it is either Aleph J or F5. I know I love the sound of 2nd harmonic from experience with playing Bass guitar.
So Aleph J I predict will be my favourite (Well F3 will be my favourite for headphones). The only adjustment is for higher bias for 4Ohm load. I think the Aleph 30 or was it 3 (or was it both) was biased to give 60W into 4 ohms.
EUVL said:
No special problem.
However my experience tells me that the efficient layout of the heat sources gives me better chances for the reduced heat sink temp. By the way, I also like to have better spaces between each component for relaxed soldering job . . . unless the short signal path is required for better sound . . .
ahh . . . isn't this GB . . . ?
I beleive the theory is that devices mounted on a heat sink horizontally spaced is more efficient. And, devices spread somewhat evenly accross the heat sink is also good. Verticle mounting requires taller heat sinks that will not perform as good with convection. You basically get more air with a horizontal configuration.
However, there is the philosophy that devices mounted in close proximity will force better tracking, stability and DC offset at the output
I would prefer the "longer" layout rather than the square or rectangle of Peter's current boards. A board about 8-10" long with all the power devices on one side
However, there is the philosophy that devices mounted in close proximity will force better tracking, stability and DC offset at the output
I would prefer the "longer" layout rather than the square or rectangle of Peter's current boards. A board about 8-10" long with all the power devices on one side
Please correct me if i am wrong but my impression was that the board pictured is Peter's style of using short circuit paths and narrow columnar chassis. So the two channel's output devices are spaced only a few inches across from one another. Heat sinks in these Pass designs tend to be large, and nearly all chassis i come across are your standard rectangular enclosures with a face plate of about 15-19 wide. So that left and right output devices sit on the large heatsinks on either side panel and its adherent heatsink. How can Peters small board be made to meet this standard enclosure?????as per nearly all Pass lab designs. Do we buy one very elongated narrow enclosure with the power supplies either end and the circuit board in the middle?? Is there enough air convection capability in such a narrow design without drilling lots of holes in all directions for ventilation?? Or is my eyes decieving me and the board shown is actually dual mono which can be split in half??
The subject of spacing devices for heatsink mounting always comes up. I already tried to explain it few times in a past that small boards are much more practical, as they offer more options in building.
It is OK to have long board (like First Watt) in a commercial product when you deal with one heatsink type only and use that heatsink in all your other products.
With infamous GB offers, we sometimes deal with hundreds of boards and everybody uses different heatsinks, that's why I prefer to make boards suitable for EVERYBODY. Those who want to make it long, can simply add extention wires.
I'd also like to mention that at least 200 of A30 boards have been sold in a past, 300 F4 boards and 300 F5 boards, all with a compatible spacing of devices. I simply cannot do it any other way now.
Besides, those are only 30watt amps, the heat is not really an issue here.
I actually still keep four A30 boards with intention of making an X circuit. When A J schematic was released, I was hoping to modify A30 boards for J version.
So yes, I am considering AJ-X amp. See attached pic. I could make 2.5 x 8" board with center piece designed specifically for X version. Two side boards are breakable and fully fuctional single channels of Aleph J. I somehow need to figure out how to elegantly interface all 3 boards for X-men option. And also, it would finally be a long board
I'd like to keep the price below $20 including shipping. I could also offer boards for free and simply charge $20 shipping
I can use any desired pin layout for input devices (SJ74 would certainly be given priority)
It is OK to have long board (like First Watt) in a commercial product when you deal with one heatsink type only and use that heatsink in all your other products.
With infamous GB offers, we sometimes deal with hundreds of boards and everybody uses different heatsinks, that's why I prefer to make boards suitable for EVERYBODY. Those who want to make it long, can simply add extention wires.
I'd also like to mention that at least 200 of A30 boards have been sold in a past, 300 F4 boards and 300 F5 boards, all with a compatible spacing of devices. I simply cannot do it any other way now.
Besides, those are only 30watt amps, the heat is not really an issue here.
EUVL said:
I actually still keep four A30 boards with intention of making an X circuit. When A J schematic was released, I was hoping to modify A30 boards for J version.
So yes, I am considering AJ-X amp. See attached pic. I could make 2.5 x 8" board with center piece designed specifically for X version. Two side boards are breakable and fully fuctional single channels of Aleph J. I somehow need to figure out how to elegantly interface all 3 boards for X-men option. And also, it would finally be a long board
I'd like to keep the price below $20 including shipping. I could also offer boards for free and simply charge $20 shipping
I can use any desired pin layout for input devices (SJ74 would certainly be given priority)
Attachments
Peter,
I don't think you need to make both power stage in an X breakable, though I won't object either. Just one side breakable is OK.
It is IMHO better to have the break line on the non-copper side, so that the conductors will remain intact. Otherwise jumpers for the rails are not really ideal.
Below USD 20 sounds good. I might want 8 if the layout suits me and price is right, but 2-4 at least.
And please use pin layout of 2SJ109. As shown, 2x 2SJ74 will always fit to the 2SJ109 pin layout.
Cheers,
Patrick
I don't think you need to make both power stage in an X breakable, though I won't object either. Just one side breakable is OK.
It is IMHO better to have the break line on the non-copper side, so that the conductors will remain intact. Otherwise jumpers for the rails are not really ideal.
Below USD 20 sounds good. I might want 8 if the layout suits me and price is right, but 2-4 at least.
And please use pin layout of 2SJ109. As shown, 2x 2SJ74 will always fit to the 2SJ109 pin layout.
Cheers,
Patrick
Peter, I'm sorry if MHO creates a conundrum of sorts, but, it's MHO, and I tried to project that idea in my post. You do great work and service to us all but, I believe it is easy to understand my POV from the Heat sink perspective. I think my understanding is correct from my POV. Your's is also a great versital, universal, philosophy also, that makes more people happy than I could ever hope toPeter Daniel said:The subject of spacing devices for heatsink mounting always comes up. I already tried to explain it few times in a past that small boards are much more practical, as they offer more options in building.
It is OK to have long board (like First Watt) in a commercial product when you deal with one heatsink type only and use that heatsink in all your other products.
With infamous GB offers, we sometimes deal with hundreds of boards and everybody uses different heatsinks, that's why I prefer to make boards suitable for EVERYBODY. Those who want to make it long, can simply add extention wires.
I'd also like to mention that at least 200 of A30 boards have been sold in a past, 300 F4 boards and 300 F5 boards, all with a compatible spacing of devices. I simply cannot do it any other way now.
Besides, those are only 30watt amps, the heat is not really an issue here.
I actually still keep four A30 boards with intention of making an X circuit. When A J schematic was released, I was hoping to modify A30 boards for J version.
So yes, I am considering AJ-X amp. See attached pic. I could make 2.5 x 8" board with center piece designed specifically for X version. Two side boards are breakable and fully fuctional single channels of Aleph J. I somehow need to figure out how to elegantly interface all 3 boards for X-men option. And also, it would finally be a long board
I'd like to keep the price below $20 including shipping. I could also offer boards for free and simply charge $20 shipping
I can use any desired pin layout for input devices (SJ74 would certainly be given priority)
. I have no problem with your boards but, I'm after all the ideal parametors I can get(DIY) and your stuff is very well suited to everyone's position. Just not always the most ideal for me. I still go for your work that I'm intersted in even if it's not my idea of perfect Who is perfect around here??? Certainly not me
Don't worry about me, keep it up
I would be interested if someone can tell me if my Spica TC-50 will play nice and behave themselves with the Aleph J.
Specs are around 83 to 84 dB sensitivity and is a 4 ohm design. I know Mr. Pass said he designed the J more in line with 8 ohm speakers.
Does an Aleph 3 make better sense for my speakers? I have cviller's F5 boards but I'll wait on that build until I can afford a nice set of efficient speakers.
Specs are around 83 to 84 dB sensitivity and is a 4 ohm design. I know Mr. Pass said he designed the J more in line with 8 ohm speakers.
Does an Aleph 3 make better sense for my speakers? I have cviller's F5 boards but I'll wait on that build until I can afford a nice set of efficient speakers.
Hi audiojoy you dont have to mount using wires or using a very narrow chassis.
If the heat sinks are tall enough you can mount the whole pcb parrallel with the face of the heat sink.
So you can use any dimension chassis (ie width and depth) as long as the heatsinks on each side are tall enough to fit the whole pcb to it (ie one heatsink per pcb).
Have a look at the pictures here to give you a beer idea of what I am trying to say.
http://www.diyaudio.com/forums/showthread.php?postid=1847777#post1847777
If the heat sinks are tall enough you can mount the whole pcb parrallel with the face of the heat sink.
So you can use any dimension chassis (ie width and depth) as long as the heatsinks on each side are tall enough to fit the whole pcb to it (ie one heatsink per pcb).
Have a look at the pictures here to give you a beer idea of what I am trying to say.
http://www.diyaudio.com/forums/showthread.php?postid=1847777#post1847777
Hello
Hi Peter,
Could I be put down for 2?
Oh by the way this would be my first post but,
I've been researching this forum quite a bit in the
last several months. There is a wealth of information.
I'm currently collecting parts for the F5 and B1. Thanks
to Jack, Cvillar, and Nelson Pass I was able to
get started with the pcbs and some components.
Just wanted to say hello to everyone.
Eric
Hi Peter,
Could I be put down for 2?
Oh by the way this would be my first post but,
I've been researching this forum quite a bit in the
last several months. There is a wealth of information.
I'm currently collecting parts for the F5 and B1. Thanks
to Jack, Cvillar, and Nelson Pass I was able to
get started with the pcbs and some components.
Just wanted to say hello to everyone.
Eric
Thanks Thanh
got it now--- that board was for a single channel--- thats my inexperience showing here. Just thought having opposing output devices meant it was a stereo set up. Sorry my fault , ok in that case the wire connectors would be very short indeed, or if the depth of the enclosure side panel is deep enough it should be able to fit the whole circuit board onto the heatsink!!
In that case apologies for the confusion earlier on in the thread.
got it now--- that board was for a single channel--- thats my inexperience showing here. Just thought having opposing output devices meant it was a stereo set up. Sorry my fault , ok in that case the wire connectors would be very short indeed, or if the depth of the enclosure side panel is deep enough it should be able to fit the whole circuit board onto the heatsink!!
In that case apologies for the confusion earlier on in the thread.