Hi Mikerodrig27
It's been a while since I've been on diyaudio so I checked what's new on the forum when I saw your F5m solution high powered with balanced input which piqued my interest.
I've wanted to build a diy First Watt amplifier for a year now when sinceI borrowed an F8 from a friend and really liked it.
So I wonder if you have 2 sets left I can buy.
/Mikael
It's been a while since I've been on diyaudio so I checked what's new on the forum when I saw your F5m solution high powered with balanced input which piqued my interest.
I've wanted to build a diy First Watt amplifier for a year now when sinceI borrowed an F8 from a friend and really liked it.
So I wonder if you have 2 sets left I can buy.
/Mikael
Hi Mikael,
Yes, I still have more sets of the F5mX amp kits. A decent amount actually. I bet that F8 was spectacular to listen to.
I will shoot you a PM
Yes, I still have more sets of the F5mX amp kits. A decent amount actually. I bet that F8 was spectacular to listen to.
I will shoot you a PM
I'm finally making progress on my F5mX build. I now need to match the MOSFETs and then on to installation into a chassis. I am very excited to get this playing tunes in the not too distant future.
More to come...stay tuned.
More to come...stay tuned.
Here we go folks. Another F5mX is born!!!
A huge thanks to Mike for a fantastic design based on Nelson's F5m. This thing rocks hard! I'm just enjoying my first glorious tunes, and I can already say it maintains that unreal F5m sound with sparkling highs. The extra oomph of the F5mX is obvious in the low end control. The F5m has great bass, but the F5mX has that extra thump that double the class A power provides. It's an obvious improvement in low end that puts my F4 in the penalty box. I've not heard the F5 Turbo, but this feels like an F5m Turbo.
I used a Modushop 5U/500 chassis and set it up with 8 FETs per channel (IRFP140/9140). I've got it biased on 0.36R source resistors to 0.52A and 55°C heat sinks. This is a "big boy amp".
I'm listening to it right now and just want to give a special shout out to @Mikerodrig27 for all his support. I would not be listening to glorious tunes without his help.
I plan to do a little write up on my journey to help others out, but for now, I gotta crank some music up and enjoy the amp. More to come.....
Amazing amp!
A huge thanks to Mike for a fantastic design based on Nelson's F5m. This thing rocks hard! I'm just enjoying my first glorious tunes, and I can already say it maintains that unreal F5m sound with sparkling highs. The extra oomph of the F5mX is obvious in the low end control. The F5m has great bass, but the F5mX has that extra thump that double the class A power provides. It's an obvious improvement in low end that puts my F4 in the penalty box. I've not heard the F5 Turbo, but this feels like an F5m Turbo.
I used a Modushop 5U/500 chassis and set it up with 8 FETs per channel (IRFP140/9140). I've got it biased on 0.36R source resistors to 0.52A and 55°C heat sinks. This is a "big boy amp".
I'm listening to it right now and just want to give a special shout out to @Mikerodrig27 for all his support. I would not be listening to glorious tunes without his help.
I plan to do a little write up on my journey to help others out, but for now, I gotta crank some music up and enjoy the amp. More to come.....
Amazing amp!
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@birdbox awesome build. Just a quick question on the LED switch which I am presuming is a AC one looking at the number of wires as I also use the same. This AC switch is meant for direct AC and I see you are using on the SW pins on Mark's soft start board, I also use similar Lanboo led switch and I get some hum if using with SW pins of Mark's so I had to replace the LED to the direct AC wiring on the IEC socket.
Schurter 4304.4045. Coincidentally - that is the model included with the new back panel parts kits.
@ ItsAllInMyHead: thank you for the information. I am really awaiting the new chassis and back panel kits. I check every day!
The switch is nothing special. Came from Bezos bookstore. The LED illumination requires DC voltage (suggested 12-24VDC), and is just two wires (black and red on my switch). The other three wires are used for switching. One chooses the two wires of the three that meet your desired On/Off criteria (I chose button "In=Off/open", "Out=On/closed"). The switch itself can technically work with AC, or DC. Its rated to 5A according to the specs. There is no hum from my soft start board. It works great!
How is it that no matter how many amplifiers I build... I inevitably forget to order (or forgot that I ran out of) some small component. DIYer's law?
Anyway... I made some progress on the F5M-X over the week. Matched up a few 140s / 9140s. Built up the PSU and the amp boards.
Now, I just need a few mechanical components to arrive, and I'll get it in a chassis and fired up. Turns out that the 400mm perforated plates will work in a 500mm chassis, so I don't need to order more of those or rob them from another amp.
Was hoping to tidy it all up later today or tomorrow, but it will be next weekend most likely... unless I get lucky.
A huge thanks to @Mikerodrig27 for the fantastic design and straight forward build / guidance docs. Another big ol' thank you to @birdbox for grabbing a lot of the essential components.
Anyway... I made some progress on the F5M-X over the week. Matched up a few 140s / 9140s. Built up the PSU and the amp boards.
Now, I just need a few mechanical components to arrive, and I'll get it in a chassis and fired up. Turns out that the 400mm perforated plates will work in a 500mm chassis, so I don't need to order more of those or rob them from another amp.
Was hoping to tidy it all up later today or tomorrow, but it will be next weekend most likely... unless I get lucky.A huge thanks to @Mikerodrig27 for the fantastic design and straight forward build / guidance docs. Another big ol' thank you to @birdbox for grabbing a lot of the essential components.
Attachments
I did a thing!
Who was I trying to kid?! There was no way I was going to wait until this weekend to finish it up. JFETs came in mid-afternoon yesterday, so I did a quick rough in and got it into the chassis along with some initial checks before a meeting.
Tidied (sort of...) the wiring and let it cook this morning while tweaking and deciding on the initial bias between meetings. Eagle-eyed folks can probably see one oopsie in the photo, but that part won't be here until tomorrow. Made a dodo move.
Settings -
I always get this wrong, but I think I set the Iq at 5A, which gives me 10A of current capability (push-pull). One of these days, I'll understand how that all works out, particularly with balanced. I know... I should understand it, but for some reason it has yet to sink in.
Either way, I'm reasonably certain I'm dissipating about 130W per channel give or take with 8 devices per channel, 26V5 rails, and 0V300 across 0R47 source resistors.
I'll try to get a few measurements on it, but after a quick test-speaker / phone source session, I moved over to listen to some larger speakers. It needs to warm back up, but so far... groovy tunes.
A HUGE thank you to @Mikerodrig27. This project is exceptionally well thought out, and it goes together intuitively. No muss, no fuss. His documentation goes above and beyond.
For those that may want some ooooooomph and some swing for a dance party night... this could be the amp for you. It's also a helluva workout tool. Oooof, my back!
Edited to add - Sheesh, I just noticed all the dust. I guess I'd better get a Swiffer.
Who was I trying to kid?! There was no way I was going to wait until this weekend to finish it up. JFETs came in mid-afternoon yesterday, so I did a quick rough in and got it into the chassis along with some initial checks before a meeting.
Tidied (sort of...) the wiring and let it cook this morning while tweaking and deciding on the initial bias between meetings. Eagle-eyed folks can probably see one oopsie in the photo, but that part won't be here until tomorrow. Made a dodo move.
Settings -
I always get this wrong, but I think I set the Iq at 5A, which gives me 10A of current capability (push-pull). One of these days, I'll understand how that all works out, particularly with balanced. I know... I should understand it, but for some reason it has yet to sink in.
Either way, I'm reasonably certain I'm dissipating about 130W per channel give or take with 8 devices per channel, 26V5 rails, and 0V300 across 0R47 source resistors.
I'll try to get a few measurements on it, but after a quick test-speaker / phone source session, I moved over to listen to some larger speakers. It needs to warm back up, but so far... groovy tunes.
A HUGE thank you to @Mikerodrig27. This project is exceptionally well thought out, and it goes together intuitively. No muss, no fuss. His documentation goes above and beyond.
For those that may want some ooooooomph and some swing for a dance party night... this could be the amp for you. It's also a helluva workout tool. Oooof, my back!
Edited to add - Sheesh, I just noticed all the dust. I guess I'd better get a Swiffer.
Sooooooooooooooo.... I may have irritated a few folks while carefully testing <cough> the amp. I have plenty of amps that sound just lovely at what I call "don't wake wifey" levels. If you're going to put heat into a room, move some air!
Let's just say it'll make silly speakers do silly things that make silly people want to do even sillier things.
The nuance in Maynard's vocals at incredible SPL is just <chef's kiss>.
Seriously though... It's a keeper.
Let's just say it'll make silly speakers do silly things that make silly people want to do even sillier things.
The nuance in Maynard's vocals at incredible SPL is just <chef's kiss>.
Seriously though... It's a keeper.
Ha ha! That is awesome! I haven't listened to Tool in forever. I had a friend years ago who demoed his Polk SDA SRS 1.2TL speakers with tool. The drum hits were pretty impressive.
I am glad you like it!
I am glad you like it!
Mike, I have a set of Harris 240/9240 from your testing how many pairs did you use that sounded the best?