The 2.0 & 4.0 I have are Dayton PMPC Met. PolyPro's.
They are leftover from another project.
Would they be ok?
I can pick them up easily.
They are leftover from another project.
Would they be ok?
I can pick them up easily.
use the 4.0 daytons...they are actually quite good.
I am beginning to think that you need to build a moskido...DC version
I am beginning to think that you need to build a moskido...DC version
OK, the massive cone movement no longer happens if I let the Aikido warm up for 30 seconds before I turn on the amplifier.
What mosFET setup would you recommend?
Those LJM L20 kits look good.
I really only need about 50wpc for my purposes.
Those LJM L20 kits look good.
I really only need about 50wpc for my purposes.
The two that I would recommend would be:
1. Pass F5 - or new F5 turbo
2. Moskido - Aikido front end mated to some nice BUZ MOSFETS
The Moskido would be more challenging build and will require some point to point wiring or some perfboard or DIY PCB action. The F5 has boards available...not sure on the turbo version.
I have both a Moskido and a modified F5 with dual output pairs using Toshibas.
From overall sound I like the Moskido but for room thumping power the dual output F5 wins.
Either one should give you plenty of power.
1. Pass F5 - or new F5 turbo
2. Moskido - Aikido front end mated to some nice BUZ MOSFETS
The Moskido would be more challenging build and will require some point to point wiring or some perfboard or DIY PCB action. The F5 has boards available...not sure on the turbo version.
I have both a Moskido and a modified F5 with dual output pairs using Toshibas.
From overall sound I like the Moskido but for room thumping power the dual output F5 wins.
Either one should give you plenty of power.
I'm not too scared of P2P wiring I'm really building this for quality.
So long as I have good instructions I can build anything.
The BUZ MOSKIDO would be fine if I have a mentor.
So long as I have good instructions I can build anything.
The BUZ MOSKIDO would be fine if I have a mentor.
Taking the sound comparison off the table as both are proven excellent sounding amps - that is not the question - it may come down to cost/complexity of build.
F5 - both amp and PSU boards readily available
1 xfomrer - simple layout and quite simple to build
Need a big chassis with large sinks
Moskido
2 PSUs needed although the aikido all in one is a good option for the tube section
Bias section needed - Bob's version has been built the most and seems to work well but you have to DIY on perfboard or make a PCB for it. My V+/- was a little low and could not get it to work so I ended up finding an elegant solution with a ready made PCB - the Pass Burning Amp II bias section.
The MOSFET section can be easily done P2P as it is a simple connection.
You will need 4X coupling caps which can add up if you go with high end
The Moskido thread is a really good read and all the schematics are there.
Not sure if this helps or not so in my opinion it comes down to how much you want to spend as that is really the big difference between the 2. You can not go wrong either way. The F5 could be built for half the cost probably.
F5 - both amp and PSU boards readily available
1 xfomrer - simple layout and quite simple to build
Need a big chassis with large sinks
Moskido
2 PSUs needed although the aikido all in one is a good option for the tube section
Bias section needed - Bob's version has been built the most and seems to work well but you have to DIY on perfboard or make a PCB for it. My V+/- was a little low and could not get it to work so I ended up finding an elegant solution with a ready made PCB - the Pass Burning Amp II bias section.
The MOSFET section can be easily done P2P as it is a simple connection.
You will need 4X coupling caps which can add up if you go with high end
The Moskido thread is a really good read and all the schematics are there.
Not sure if this helps or not so in my opinion it comes down to how much you want to spend as that is really the big difference between the 2. You can not go wrong either way. The F5 could be built for half the cost probably.
Also, not to start a flame war or anything but a Class A power section will blow away a chipamp if built properly. My first DIY amp was an LM3886 and it is a damn fine little amp but there is a difference and a pretty big one IMO...
Just make sure you get BIG heatsinks. If there is even a remote possiblity that you would go for 4X MOSFETS per channel then you will will want at least a 5U size case.
Just make sure you get BIG heatsinks. If there is even a remote possiblity that you would go for 4X MOSFETS per channel then you will will want at least a 5U size case.
I have a couple of heatsink options.
One is 5" High x 12.25" Long x 2.5" Thick.
The Fins are 1-7/8" high .25" thick.
The base is about .5" thick.
I have 6 of them.
Would this be suitable for the F5 Turbo V2?
Otherwise I have a 12x18x4 anodized I can cut in half.
One is 5" High x 12.25" Long x 2.5" Thick.
The Fins are 1-7/8" high .25" thick.
The base is about .5" thick.
I have 6 of them.
Would this be suitable for the F5 Turbo V2?
Otherwise I have a 12x18x4 anodized I can cut in half.
Those sinks would be enough for a single pair of MOSFETS running pretty hot but two pairs per channel might be pushing it.
Also, I mentioned a 5U case above...for two pairs a 4U rack would be good although 5U would be even better....
3U = 120mm tall = 4.7"
4U = 165mm tall = 6.5"
My pass F5 uses a 4U case 300mm(11.8") deep and it cools the two pairs per channel pretty good.
Looks like you are just on the borderline. Worst case would be to build it and maybe you have to bias it down a little more.
I forget exactly but I am running about 4A bias per channel (1A per device) on the F5 and about 3A per channel (1.5A per device) for my Moskido and it runs pretty hot.
My Moskido is in a 3U case so I can not add more MOSFETs in the current case its in.
Also, I mentioned a 5U case above...for two pairs a 4U rack would be good although 5U would be even better....
3U = 120mm tall = 4.7"
4U = 165mm tall = 6.5"
My pass F5 uses a 4U case 300mm(11.8") deep and it cools the two pairs per channel pretty good.
Looks like you are just on the borderline. Worst case would be to build it and maybe you have to bias it down a little more.
I forget exactly but I am running about 4A bias per channel (1A per device) on the F5 and about 3A per channel (1.5A per device) for my Moskido and it runs pretty hot.
My Moskido is in a 3U case so I can not add more MOSFETs in the current case its in.
I can put some fans on the inside of the chassis to help circulate from the back side.
I could also heatsink the topside of the chips with heatsinks on the pressure plate.
I can cut aluminum on my table saw to I could cut the 6 heatsinks I have and create some 4U sinks to join together with a flat piece of aluminum.
Do you think any of those are a viable solution?
I could also heatsink the topside of the chips with heatsinks on the pressure plate.
I can cut aluminum on my table saw to I could cut the 6 heatsinks I have and create some 4U sinks to join together with a flat piece of aluminum.
Do you think any of those are a viable solution?
What do you think of the LJM L20 Kits?
He is a member here and the kits are readily available.
It looks like the Version 7 is 4 pair of transistors per channel.
They run up to +-70VDC and ljm_ljm says they run pretty cool (comparatively).
He is a member here and the kits are readily available.
It looks like the Version 7 is 4 pair of transistors per channel.
They run up to +-70VDC and ljm_ljm says they run pretty cool (comparatively).
If it were me I would start out with the Pass F5. The amps typically run off 18V toroids putting out around 24-25VDC. This keeps things very simple. PSU capacitors can be had in very high capacitance relatively inexpensively versus going greater than 35V say.
I would avoid fans.
You could try it with 2 of the heatsinks you have and just keep an eye on the bias. If you need more sinking then deal with it then. You should be able to get at least 3A per channel bias based on the dimensions you gave.
Go with a 600VA 18V secondary for the F5. Its a monster but will give you lots of headroom. Antek is the unit of choice.
I would avoid fans.
You could try it with 2 of the heatsinks you have and just keep an eye on the bias. If you need more sinking then deal with it then. You should be able to get at least 3A per channel bias based on the dimensions you gave.
Go with a 600VA 18V secondary for the F5. Its a monster but will give you lots of headroom. Antek is the unit of choice.
Perfect, CeeVee will provide me his Gerber files for F5 Turbo tomorrow.
I may pick up a standard F5 on eBay though.
35V caps will be nice to use.
I may pick up a standard F5 on eBay though.
35V caps will be nice to use.
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