Yes, you can absolutely build it, you have the experience/background. 
I’m curious as to why you need that much power? Sound reenforcement in a theater or church? Extremely inefficient speakers? Do you listen to Zeppelin and Ozzy at concert levels? 100wpc of real class-A is an enormous and power amplifier, hence the need for a pair of gigantic chassis.
A huge percentage of builders find that the 25wpc Class-A amps are much more than they need and sound more powerful than any of their previous amplifiers regardless of rated power.
My suggestion is to look at the standard firstwatt amps, Aleph J, F5, F6, M2x, etc... and build the one that is the most interesting to you, since they (truly) all sound fantastic.
Real Class-A is a thing. You will be amazed and pleased.
I’m curious as to why you need that much power? Sound reenforcement in a theater or church? Extremely inefficient speakers? Do you listen to Zeppelin and Ozzy at concert levels? 100wpc of real class-A is an enormous and power amplifier, hence the need for a pair of gigantic chassis.
A huge percentage of builders find that the 25wpc Class-A amps are much more than they need and sound more powerful than any of their previous amplifiers regardless of rated power.
My suggestion is to look at the standard firstwatt amps, Aleph J, F5, F6, M2x, etc... and build the one that is the most interesting to you, since they (truly) all sound fantastic.
Real Class-A is a thing. You will be amazed and pleased.
6l6, thank you for your input. I don’t listen to music very loud. In fact I think I very modest levels. I have a Mc amp that when playing the meters are generally around 3 watts average and possibly peak at 30ish occasionally. The speakers I want to power are only 86db efficient. Those are not what I’m using on the Mc system. Right now I power those speakers with a pair of 125w Bob Latino monoblocks I built. They do absolutely fine. I’ve never owned a class A amp but since a kid always wanted to. I guess I really don’t know what I’m going to get via class A power vs AB output. I do understand the concept of operation though. I may end up doing something smaller after learning in this thread.
Hello again, I’ve confirmed my game plan after getting some info earlier build the F5T-V2. I’m concerned my speakers are pretty inefficient and therefore am skeptical to build the standard F5. Anyway, I was going to order parts and I have a question about ordering the matched JFETs. There are (4) choices. Can someone tell what the difference is or which ones I should go with to build the F5T-V3. I am also assuming the F-5T V1/2 TRANSISTOR KIT is correct for this amp? Thank you again in advance. Joe
F-5T V1/2 Transistor Kit – diyAudio Store
And the LSK170/LSJ74 matched quad from this link -
Linear Systems Matched JFETs – diyAudio Store
And the LSK170/LSJ74 matched quad from this link -
Linear Systems Matched JFETs – diyAudio Store
5U deluxe chassis, back panel kit, amp PCB kit, PSU board,
Deluxe 5U Aluminum – diyAudio Store
Back panel parts kit plus PCB / Transistor / Diode mounting parts kit – diyAudio Store
Universal Power Supply – diyAudio Store
F-5T – diyAudio Store
Deluxe 5U Aluminum – diyAudio Store
Back panel parts kit plus PCB / Transistor / Diode mounting parts kit – diyAudio Store
Universal Power Supply – diyAudio Store
F-5T – diyAudio Store
I ordered the amp boards and power supply boards for the F5T v2 (50wpc) and I have a few questions regarding the power supply. I ordered (2) of the universal boards thinking I would use one per channel with either dual (500va) transformers @ (24 0 24) or I was considering (1) larger 1000va with double (25 0 25) (25 0 25) secondaries to get the +-32vdc rails. I am trying to understand what I can achieve by raising the rail voltage to say 48vdc and can this be done by without having to change parts off the BOM. I am pretty new at this hobby and would have no idea how to reinvent the wheel. Any suggestions or thoughts are welcome.
My opinion blocks are the best way to go.... more than that though, when you start talking about V3 or even more, your problem is heat. All that hot stuff in one box is harder to cool. I think monos sound better even if heat were not an issue, but that is a lessor factor to controlling heat in the box.
JT
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General hookup wire.... I built the same amp 3 times. 1 cost $500, 2 cost $700 the third, well $850. I knew the $850 must be better.
5 Friends did a blind test and only one chose the $850. That's not to say the 850 wasn't better, just I need more audiophile friends... whatever that means.
