F5 V3

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I ran the suspected channel for over three hours last night and made adjustments to try to keep things where they should be, I ended up with a very stable .604 bias and 9 something mV.
This pic was from a 1 hour warm up from a cold start today.
It definitely needs an hour to stabilize from what I saw on the meters.
I could hold my hand on the heat sinks all day long, just warm to the touch.
So copy and paste to the other side and I should be good?
 

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Maybe? After building the Amp Camp Amp, I was immediately like: "Okay. I should have built a bigger one.." I guess I want to keep my options open for F5 turbo versions?

Which, while I've got your ear... Should I/Could I be building a higher powered (50watt into 8ohm) F5 as Nelson describes in the beginning of the F5 Turbo document? Is there any reason I should do the regular F5 first? It looks like a higher voltage power supply and a couple of other upgraded components would double my wattage?

"Increasing the power supply voltage is the obvious way to get more power out
of an F5. You can simply raise the supply rails to +/-32 Volts and get 50
watts into 8 ohms right away without other modification. 24 V AC secondaries
on the power transformer will do it."

Thanks.. Feel free to tell me to read more forums...
 

6L6

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Joined 2010
Paid Member
jan492 - As the ACA is about a 3W amp, any of the Firstwatt will be so much more power you'll be genuinely astounded.

IF you want to do a high power F5 (F5Tv1) you need two things - real Toshiba Jfets since they are being run above spec and bigger heatsinks.

Build one of the amps as designed, you'll love it.
 
I used terminal blocks & connectors instead of direct soldering (which is obviously better) for the simple reason that I want to easily repair anything if needed.
That was useful when I had a leaking condo and it is going to help again to change resistor s on the amp boards.
 
I did not obsess about the DC off set, kind of arrived in that range trying to dial it up.
I adjusted each pot watching the meters and never letting the dc off set to get over 50mV before adjusting that one back to close to zero.
My target was .606 bias, complete arbitrary number I came up with with absolutely no idea why.
As I got closer to my target values, seeing how the pot adjustments read out on the meters, I made the adjustments finer.
Until I hit my target point, at that point I put the lid on it and let it stabilize and made adjustments to keep close to my target.
Those are the numbers I ended up with.
Did I do it wrong?
 
Ok, here are a couple.
No frontal nudity as it is only a piece silver anodized aluminum (should have got black) with nothing on it.
Anyway, I would like to give a big THANK YOU to all have helped me with this project.
Without your guidance and help, I would not have reached this point.
This is truly a great community.
Anyway, going to listen it to it sometime this weekend
 

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I hooked it up to some equipment and speakers that I had laying around, nothing fancy.
So, no pops on power up/down.
Dead silent in between tracks, no buzz.
Listened to Patty Griffiths 1000 kisses CD, which i am very familiar with.
Sounded exceptionally good even with sub par equipment.
 

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