• These commercial threads are for private transactions. diyAudio.com provides these forums for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members, use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

WTB Firstwatt Clone F2 PCB boards

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Member
Joined 2006
Paid Member
vonfilm said:
I am in for 1 on the wiki. Why is there not more interest in the F2?


Maybe its because you can get about any FW amp known to us right now except F2 on PCB.

The list of 33 so far is not bad. The F3-F4 list took a while to reach 50 units each.
The F5 I think took a few days only.

Even a:clown: like me can build an F2 point to point. My first Pass amp.

This is reason enough however for anyone to want to build an F2 with a real PCB. Mine looks like :cuss:
 

Attachments

  • f2small.jpg
    f2small.jpg
    15.4 KB · Views: 1,811
Member
Joined 2006
Paid Member
HaLo6 said:
Is this a good noob project.... I am very green at this... but reading "The Art of Electronics" is getting me excited about all the possibilites ... and how much is approximate cost?


Some recommended reading. F2 is good for full range drivers typically.. like fostex lowther, tang bang.

http://www.firstwatt.com/downloads/cs-amps-speakers.pdf

The heatsink's are likely most expensive part. Needs to dissapate some 100 Watts each channel constantly for this model. Transformer second most expensive?

PCB's 30 bucks or so, parts each channnel 30-50 dollars each.

Connectors drill taps, etc casing metal, the ski is the limit.

A more universal amp maybe the F5.

That being said - F2 circuit is pretty simple to roll. A voltmeter and a fire extinguisher are recommended.
:att'n:
 
I am in. That amp is so special. Just the thing for fullrange speakers, so 1 set for building and 1 set for the growing PCB collection;)

:)

Edit @HaLo6, this is a specialty amp with 5 watt output power and no damping factor, so it is not useful for the usual speakers with a crossover. The F2 amp need efficient singledriver speakers to sound good.

Anyone volunteering to do a Sonido GB??;)
 
frugal-phile™
Joined 2001
Paid Member
The speakers i build really like transconductance amps. F2 is Nelson's 2nd attempt so he hopefully learned from the F1. I expect this amp could well be a SS unit that actually rivals the tube amps we have built.

and 2 people, NetList & Scottmoose have F2s and VERY highly recommend them (Netlist has Fonkens)

dave
 
Member
Joined 2003
Paid Member
50 needed to proceed correct? Its always good to have a few extra for the collection, I might just have to increase my order to get this thing rolling. Just got my FE127E's.....pumped!! I was a little impatient, I made enclosures out of cardboard boxes, connected to a BOZ>>Zen amp.....unreal!! Leaning towards the Fonken, or the box discussed in the Full Range Reference thread.

Which do you recommend Dave?

I think this is the one from that thread:
This looks a little bit easier to construct......
 

Attachments

  • 127ref-project.jpg
    127ref-project.jpg
    59.4 KB · Views: 1,226
Member
Joined 2006
Paid Member
OT alert

I know I am drifting out of focus here -
Dave,
I have an old set of lowther medallion cabinets that I dont use no more. Do you know of the 8" fostex's or a direct fit, or any other that you can think of. The measurements look close....

I am using the F2 to drive a Eminence Definemax 15LO in an open baffle. It does a good job. I have to drive the gain up on the crossover to keep up with the F4's output on the lowthers.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.