My vote is for seperate power stage PCBs
I agree with Brian, without active cooling It is looking like you would have to have monster heatsinks probably with copper heatspreaders or active cooling to pull off a safe amp with Peter's PCB if you mounted all 6 devices on the PCB. While this does not preclude using Peter's design by any means, I think Brian's design is more accessible and practical to a broader set of users. Both are so cool though.
I agree with Brian, without active cooling It is looking like you would have to have monster heatsinks probably with copper heatspreaders or active cooling to pull off a safe amp with Peter's PCB if you mounted all 6 devices on the PCB. While this does not preclude using Peter's design by any means, I think Brian's design is more accessible and practical to a broader set of users. Both are so cool though.
I think the solution to that is very simple. Since my board is about the same size as Brian's Aleph Mini board (yet still allows functionality of both A30 and A mini), all it needs is additional output boards for broader (and more thermally efficient) applications. This way you will have the best of both. I'd like to note that although my board allows all 6 Mosfets (and power resistors on board), the front end section layout is not compromized in any way because of that. I actually think it has some advantages.
As to the output boards, I would see them as rows of 6 devices, which can be broken in half, if only 3 per side are needed. This would give a choice to people getting one board for two channels or one per channel for more power. There would be 2 output boards per set.
I'm not gonna mention here possibilities of applying the boards to Aleph X as well
Still, no matter what verdict in here is, I will produce my board anyway, as I believe it's a way to go with a small Aleph. I did a drawing, showing 6 devices mounted, with copper spreaders (which definitely would be very advantegous). As you can see, the size is about right for R-theta heatsinks ( 6" x 11") which are perfect for one channel of Aleph 30.
As to the output boards, I would see them as rows of 6 devices, which can be broken in half, if only 3 per side are needed. This would give a choice to people getting one board for two channels or one per channel for more power. There would be 2 output boards per set.
I'm not gonna mention here possibilities of applying the boards to Aleph X as well
Still, no matter what verdict in here is, I will produce my board anyway, as I believe it's a way to go with a small Aleph. I did a drawing, showing 6 devices mounted, with copper spreaders (which definitely would be very advantegous). As you can see, the size is about right for R-theta heatsinks ( 6" x 11") which are perfect for one channel of Aleph 30.
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I don't really see advantages in a wider pcb. It's harder to implement, the traces are longer, and for some reason it looses the appeal.
Everybody was commenting on Brian's original Aleph Mini as beautiful and cute creation. Well, I want to create something like that with Aleph 30.
And I'm trully not concerned with heat problems. With copper spreaders it will run cooler than with bigger board without spreaders.
Everybody was commenting on Brian's original Aleph Mini as beautiful and cute creation. Well, I want to create something like that with Aleph 30.
And I'm trully not concerned with heat problems. With copper spreaders it will run cooler than with bigger board without spreaders.
I can't help thinking that Brians layout is more simple to implement. If this is to reach a broader audience, I dont think copperspreaders wil be appealing (to most ppl) Also if the output boards are to be used in Peters design, you would have to leave out 14 resistors on each board. Also there would have to be 2x4 clearly marked pads on each board, for taking the leads to the outputboards. Unless you mean to take out 18 leads from each pcb.
So for the groupbuy, my vote is still for Brians layout. BTW, Peters layout is quite amazing, with all that stuff fitted on that little pcb And cute it is, for sure As for the heat, I was playing a little this weekend. It occured to me that I had all the stuff lying around for a ZenV1 amp. I stumbled over a pcb for it I couldn't resist and did put it together. The chassis is my "play" chassis
Considering this is 2x10 watts, the amp runs amazingly hot. The sinks not being huge, but not excactly small either, I was stunned about the temp it ran at. One Fet per sink! I would never mount three on each of them. Have a look .
Steen.
BTW it sounds great, except for the psu ripple that spills over at the output. I intend to get rid of that though.
So for the groupbuy, my vote is still for Brians layout. BTW, Peters layout is quite amazing, with all that stuff fitted on that little pcb
And cute it is, for sure As for the heat, I was playing a little this weekend. It occured to me that I had all the stuff lying around for a ZenV1 amp. I stumbled over a pcb for it I couldn't resist and did put it together. The chassis is my "play" chassis Considering this is 2x10 watts, the amp runs amazingly hot. The sinks not being huge, but not excactly small either, I was stunned about the temp it ran at. One Fet per sink! I would never mount three on each of them. Have a look .
Steen.
BTW it sounds great, except for the psu ripple that spills over at the output. I intend to get rid of that though.
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I agree with Peter, I had no problems with one of my Zens dissipating 100W per channel on huge heatsinks with the only 2 mosfets which were fairly close together. With the A30 this dissipation is shared between 6 FETs so the junction temperature will be even lower. If one still think it gets too hot one can always decrease bias current... there are plenty of topics on how to do that
steenoe said:
Actually it's only 7 wires, if you want to spread the mosfets: you leave mosfets on one side on the board, all resistors stay on board as well, and you place only 3 mosfets outside the board. You will need 3 wires to connect gates, 3 wires to sources, and one wire for shared power rail.
How many wireas are used with Brian's layout?
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I think we should make both. The reason i like the mini a is because 10watts in class a is plenty for me. ALso these mini a's that brian built are on there way to me. I believe the board that peter are awesome but are to close together If peter was to make teh board cut'able to mount the fets on the heatsink away from the main board it would be good. My intention here is to provide a kit small for people that are not ritch to build a aleph 2 1 or 3 these boards are small cheap and easy to build Im thinking seriouly about selling all my aleph 2 parts except heat sinks. that is 2 x 1kva victoria magnetic's transformers all the caps 2 brian gt main boards fully stuffed the output boards the binding postes and a few other goodies. so i can build up 6 channels of the mini'a's 3 per speaker as mine are going to be tri'amped..It's sad that i spent a fortune on my Aleph 2's but in the end i think tri'amping would sound better.
I'm also coming to conclusion that we should run both offerings. It seems like there are people who prefer one over the other, and I would suspect it's about 50/50 split.
Brian and Jason can go on with their boards as part of a group buy, and I will offer the boards on basis of individual inquiries.
I already have seen interest in at least 30 of them, so I'm pretty sure that whatever I invest will show return. I will match the prices with the group buy offering.
Brian and Jason can go on with their boards as part of a group buy, and I will offer the boards on basis of individual inquiries.
I already have seen interest in at least 30 of them, so I'm pretty sure that whatever I invest will show return. I will match the prices with the group buy offering.
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Joined 2002
You see, usually the reason for creating group buy is to make sure that whatever you order from manufacturing place will be sold and you are not loosing any money.
In case of those Aleph 30 boards, I'm pretty shure that whatever I have in stock will be sold anyway, so I don't really need a group buy assurance.
I will just order the boards, and when they bacome available, I will be selling them to whomever is interested. The price will reflect pretty much my cost.
Group buys had recently gained bad reputation, that's why I'd rather avoid being associated with one
I can have the boards ready in 10 days.
In case of those Aleph 30 boards, I'm pretty shure that whatever I have in stock will be sold anyway, so I don't really need a group buy assurance.
I will just order the boards, and when they bacome available, I will be selling them to whomever is interested. The price will reflect pretty much my cost.
Group buys had recently gained bad reputation, that's why I'd rather avoid being associated with one
I can have the boards ready in 10 days.
Again to set the record straight.
Peter’s board (which is very nice) is an Aleph 30 clone. It could be used to actually make one of Mr. Pass' amps at a very reasonable price. Note that the circuitry IS patented so Peter can NOT make money on the sale of them.
Also, I am too highly impressed with Peter’s layout and the size of the "total" package.
Brian/Jason's board is the outcome of Grey's thoughts of a Mini-A, a tiny class-A amplifier. The output boards were an afterthought.
Again, the circuitry IS PATENTED and Brian nor Jason can make a profit from its sale.
I think Peters clone is a great project but again think it deserves it's own thread.
Peter’s board (which is very nice) is an Aleph 30 clone. It could be used to actually make one of Mr. Pass' amps at a very reasonable price. Note that the circuitry IS patented so Peter can NOT make money on the sale of them.
Also, I am too highly impressed with Peter’s layout and the size of the "total" package.
Brian/Jason's board is the outcome of Grey's thoughts of a Mini-A, a tiny class-A amplifier. The output boards were an afterthought.
Again, the circuitry IS PATENTED and Brian nor Jason can make a profit from its sale.
I think Peters clone is a great project but again think it deserves it's own thread.
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Joined 2002
I'm not trying to make proffit im trying to offer people a decent price. Alowing me to get as many people interested brings down the price for the boards also making it so i can buy a few set's for my self.
The only proffit i would get is making kits and adding a few dollars to get a few components for my self free or cheaper. that is it. And to me that sounds fair for doing all the work. : O )
The only proffit i would get is making kits and adding a few dollars to get a few components for my self free or cheaper. that is it. And to me that sounds fair for doing all the work. : O )
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Joined 2002
If Peter will be ordering the A30 design, then I respectfully submit that the alternative buy be for the true "mini A". The price of the boards will be much lower without the "wings". Just my two cents.
Peter can serve the mid-price, mid-power market. Jleaman can serve the low-price, low power one.
Peter can serve the mid-price, mid-power market. Jleaman can serve the low-price, low power one.
Banned
Joined 2002
The purpose of a group buy is to enable many like-minded people to capitalize on quantity ordering. Ordering of PCB's, components or what ever.
In this case (Peters too), no money should be made on the PCB's since it is patented circuitry for Mr. Pass.
I would buy a complete "kit" of parts to build a pair of Mini-A's. But in order to stay true to the patent, you would be obliged to sell just the PCB's at cost too.
However the components to stuff the boards are fair to sell at a profit. The sheer numbers ordered would almost guarantee that the price would be reduced compared to individual orders.
The "kits" and shipping are where the owner of a GB would make their "profit", whether it is money or parts for there own use. The profit taking is what separates the hobbyist from the poacher. If you’re doing GB's for money you prolly need to find a real job. Running GB's is not how you send your children to college. If you're doing it for parts or drinking money, I'll be happy to throw a few bucks in to encourage the hobby (drinking OR building, just not concurrently).
In this case (Peters too), no money should be made on the PCB's since it is patented circuitry for Mr. Pass.
I would buy a complete "kit" of parts to build a pair of Mini-A's. But in order to stay true to the patent, you would be obliged to sell just the PCB's at cost too.
However the components to stuff the boards are fair to sell at a profit. The sheer numbers ordered would almost guarantee that the price would be reduced compared to individual orders.
The "kits" and shipping are where the owner of a GB would make their "profit", whether it is money or parts for there own use. The profit taking is what separates the hobbyist from the poacher. If you’re doing GB's for money you prolly need to find a real job. Running GB's is not how you send your children to college. If you're doing it for parts or drinking money, I'll be happy to throw a few bucks in to encourage the hobby (drinking OR building, just not concurrently).
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