Building an F5 Turbo v2 (in-Progress)

I'm new to this and have been reading threads and posts here at the forum about the F5 amp for days now. I must say it's quite some to take in and get goin' for a noob...

Anyway, the best way to get started is to get started, so here I go!

First of all I need the boards... There seems to be quite a few versions, and places to get them from. At the same time, it's not obvious which ones to get and which ones to avoid.

I've been trying to find out where to buy the PCB's for the F5Turbo v2. , since the "diyAudio F5T ver. 3 PCB" is apparently sold out. (I am on the list to get notified if and when they are back in stock.) Does anyone know if they will be back to order? If so, any idea when?

And if they won't be back, is there any other place to order them from? Or possibly a kit? I live in Sweden, if that makes any difference...

Appreciate any help I can get to get started!

A some what lost Noob...
 
Just want to say that, after two years or so (due to problems getting the cases built), a friend and I have finally completed our F5 Turbo v3 project. Or maybe I should call it our F5 Turbo v3 on steroids project: 26 dB gain; 8 Fairchild output devices per channel; 2 x 1.4 kVA transformers; 750 joules energy storage per channel; 135 pure class A watts/ch into 8 ohms; 100 kg weight divided into four separate cases (2 amp modules, 2 power supply modules). The break-in period, I'm told, is fairly lengthy, but even after 40 hours, the amp is proving both ultra-transparent and almighty powerful beyond what I've noticed with a number of well-regarded $10K to $20K commercial models...kudos and gratitude to Nelson Pass for so generously making his circuit designs available to the DIY community!
 
Question for you folks.. forgive me if im missing something obvious to some of you.
im building sigfried linkwitz lx521. It requires 8 channels of amplification capable of driving 4 ohms with reference-like quality.

As a personal challenge, Im considering building 4 channels of the V2 F5turbo to drive the four 4 ohm woofers in the Linkwitz lx521.

I use a home built PassDIY Pearl 2, and home brew Aleph P1.7 with roughly about 10-12db gain.

1) Can someone confirm that this amp design would be suitable to drive these woofer loads? (im assuming it is easily stable at 4ohms nominal)
2) how much voltage gain does the F5Turbo v2 produce? I cant find this info...

I need to know how much gain the F5turbo provides, so i can match the channel gain for the mids and tweeters. (i will probably just use the 4 chip amps i already have, to drive the mids and tweeters (at least for now)). i want to know this info before building because im not yet decided upon what amp to build to drive the lx521.
 
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Question for you folks.. forgive me if im missing something obvious to some of you.
im building sigfried linkwitz lx521. It requires 8 channels of amplification capable of driving 4 ohms with reference-like quality.

As a personal challenge, Im considering building 4 channels of the V2 F5turbo to drive the four 4 ohm woofers in the Linkwitz lx521.

I use a home built PassDIY Pearl 2, and home brew Aleph P1.7 with roughly about 10-12db gain.

1) Can someone confirm that this amp design would be suitable to drive these woofer loads? (im assuming it is easily stable at 4ohms nominal)
2) how much voltage gain does the F5Turbo v2 produce? I cant find this info...

I need to know how much gain the F5turbo provides, so i can match the channel gain for the mids and tweeters. (i will probably just use the 4 chip amps i already have, to drive the mids and tweeters (at least for now)). i want to know this info before building because im not yet decided upon what amp to build to drive the lx521.
This proposal sounds back to front.

"requires 8 channels of amplification capable of driving 4 ohms with reference-like quality." and then uses 4 channels of ClassAB chipamps to drive the Mids and Trebles.
And proposes enormous ClassA power to drive the bass only channels.

Surely a ClassAB to drive each bass only driver and use some reference quality ClassA to drive the mids and trebles would be a better distribution of resources.