diyAudio F5 Build Guide

6L6, great work on putting together the new guide over at new build guide area:
All Guides - diyAudio Guides
To think that your first indication that you were putting it together dates to May, reinforces the sense in being patient with this sort of venture. If only there was more time available for us all.

Anyhoo, would you be able to provide some more detail for me by answering two key questions?

Refer the pic below from your guide (that I've linked from Post #32):

IMG_1852.jpeg



What are the details on (what Zen Mod informs me is an L-bracket) the mounting device for the toroidal transformer? A clear photo would be great, if you have it, and any info on where you sourced it or how you fabricated it would be appreciated.

The second thing is, what's the black box to the left (in picture) of the transformer with power cables entering and exiting the item? Is it just some fast connection/disconnection junction box? Or something else? Regardless, some more detail would be appreciated to, a) satisfy my curiosity and b) potentially offer a worthwhile feature to copy.



I'm greatly appreciative of this aspect of the F5 build guide. I'm planning on building an Aleph J and the detail you've given around the PSU side of the F5 is filling in a few gaps in my knowledge and giving me some good ideas to think through.


:up:


EDIT:
6L6 pointed me to one of his other build threads to answer my questions:
F6 Illustrated Build Guide
 
Last edited:
Hello

I'd like to say thanks very much to 6L6 for the information on page 4 (and in all the build guides of course). Your dedication in helping others is inspiring.

I have just started ordering parts for an F5 and have a couple of questions:
I read somewhere in one of the many threads some reservation about the Antek transformer, though Mr. Pass seemed to weigh in with a positive comment about it - I'm looking at this one - AS-3218 - 300VA 18V TRANSFORMER.
Yay or nay and if nay what are some options?

And where do I find that nifty lead spacer / bender that I see in your post on page 4 with the resistor in it? Have to have it I do believe.

Thx
Dave
 
Hi All,

Having just completed my first ACA amp project, I was very impressed by the result that I immediately followed up with a second ACA build which, together with the first was bridged, and both are now connected and functioning as balanced mono-blocks!

I am keen to build the F5 but would like to know from experienced builders if all components are still available to successfully complete an F5 build?
Any advice or shared experience would be appreciated.
Thank you.
 

6L6

Moderator
Joined 2010
Paid Member
Linear Systems Matched LSJ74/LSK170 JFET pairs (Grade B) – diyAudio Store

Deluxe 4U Aluminum – diyAudio Store

F5 – diyAudio Store

Universal PSU – diyAudio Store

AS-3218 - 300VA 18V Transformer - AnTek Products Corp

Currently the back panel parts kit and the PCB kit is out of stock, however all that is available at other sources, and you need wire, a few bits and pieces and PSU components anyway, so you'll need to order things from an electronics distributer regardless.

Basically speaking, the Jfet are currently available, so you can build one.
 
Hi All,

Having just completed my first ACA amp project, I was very impressed by the result that I immediately followed up with a second ACA build which, together with the first was bridged, and both are now connected and functioning as balanced mono-blocks!

I am keen to build the F5 but would like to know from experienced builders if all components are still available to successfully complete an F5 build?
Any advice or shared experience would be appreciated.
Thank you.

Hello Nuryev

I am piecing together an F5 as well. I likely won't have everything until December and I do believe I will be asking the best wife for the Deluxe 4U case for Christmas!!!

I will probably be posting my build and it would be great if you did as well.

Regards
Dave
 
Linear Systems Matched LSJ74/LSK170 JFET pairs (Grade B) – diyAudio Store

Deluxe 4U Aluminum – diyAudio Store

F5 – diyAudio Store

Universal PSU – diyAudio Store

AS-3218 - 300VA 18V Transformer - AnTek Products Corp

Currently the back panel parts kit and the PCB kit is out of stock, however all that is available at other sources, and you need wire, a few bits and pieces and PSU components anyway, so you'll need to order things from an electronics distributer regardless.

Basically speaking, the Jfet are currently available, so you can build one.

Hi 6L6,
Thanks for the prompt reply and the links, I will be adding them to my favourite web pages!
 
Hello Nuryev

I am piecing together an F5 as well. I likely won't have everything until December and I do believe I will be asking the best wife for the Deluxe 4U case for Christmas!!!

I will probably be posting my build and it would be great if you did as well.

Regards
Dave

Hi Trismos,
Thank you for the encouraging comment. I will be watching your progress closely. Where did you order your components?
 
Linear Systems Matched LSJ74/LSK170 JFET pairs (Grade B) – diyAudio Store

Deluxe 4U Aluminum – diyAudio Store

F5 – diyAudio Store

Universal PSU – diyAudio Store

AS-3218 - 300VA 18V Transformer - AnTek Products Corp

Currently the back panel parts kit and the PCB kit is out of stock, however all that is available at other sources, and you need wire, a few bits and pieces and PSU components anyway, so you'll need to order things from an electronics distributer regardless.

Basically speaking, the Jfet are currently available, so you can build one.

6l6 - a few questions: I am building the F5 and was looking at this Cap :https://www.mouser.ca/ProductDetail...wFf0viD3Y3RiK1i3BOqatjrTACjhZSL4oxUrd0RlFeA==
Satisfactory?
Also, I can't tell from your build guide which diodes you are using though you mention the TO 220 package... I don't suppose you have a Digi_key or Mouser prt#? There seems to be alot of variations.

One more comment - your build guide that is linked to in the DIY Audio Store for the PSU has a number of img links that just take us to the archives general page. How do we find the actual photo referenced? There are quite a few that you make comments about but of course we can't see the pics now.

Thx much

Dave
 
Firstwatt F5 amplifier v3 - diyAudio Guides

As for the PSU page, yes, sadly many of those links are corrupt.

Your capacitor looks good. :)

It appears that a few resistors as installed in the pictures in this build guide do not align to the schematic. For example, I think R13/R14/R17/R18 are 100R in the schematic, but it appears that 1K resistors are installed in this build guide. Is there a reason to adjust the values of those resistors (or am I reading this wrong)? Will be good to know since I'm in the middle stuffing my F5 amp boards. Thanks!
 

6L6

Moderator
Joined 2010
Paid Member
Dale/Vishay RN and CMF series are three-digit with multiplier in the 4th place.

If the value printed on the side reads 1000, it is 100 ohm with 0 zeros behind it, or 100 ohm.

1001 would be 100ohm with 1 zero behind it, meaning 1k

1002 is 10k, 1003 100k, 1004 1m, etc...

Sub-100 ohm have an “R” in the decimal. 10R0 is 10.0ohm
 
Switches things on and off again
Joined 2000
Paid Member
One more comment - your build guide that is linked to in the DIY Audio Store for the PSU has a number of img links that just take us to the archives general page. How do we find the actual photo referenced?

Bit of a mess, will be fixed in the future. In the meantime, you can try to salvage the images you are after from this archive:

6L6 Gallery - My Photo Gallery

The PSU photos start here: 6L6 Gallery - My Photo Gallery
 
Happy New Years to all.

I just returned from a nice little vacation in Palm Springs CA to my home in Yellowknife NT. (Canada) - from 2 weeks of basically 70F (21C) to -13F (-25C) - and I'm ready to hunker down and get back to my F5 project. I'm about to order the deluxe 4U from the DIYAUDIO Store and I would like to use the black face plate but I'm curious about the missing 8 pre-tapped M3 threads - what are these for?

As well, I happen to have a Hypex soft start module and the rocker switch with the blue led ring surround (DIYclassd.com). The module specs indicate it's good for Max 1500VA outputs and 6A continuous current. Would this be suitable for use with the F5?

Hope all is well with everyone and thanks for your continued support!

Kind regards

Dave