A quick, I am in the thought to hope, question.
Will one 800va transformer have ability to handle 4@ F5 Turbo v2 boards and live a long happy life?
Mono blocks with independent l-r channel capacitor bank boards (8@ 22,000 uf 63v 105c caps per channel).
This transformer:
AN-8425 - 800VA 25V Transformer - AnTek Products Corp
These boards:
Posh Audio - High Quality Audio Grade Components: Pass F5 Turbo V2 (4 Mosfet)
Of course I know the diy audio store has the official (to here) board version but these were a gift and I have them populated with good parts.
Thank you.
Will one 800va transformer have ability to handle 4@ F5 Turbo v2 boards and live a long happy life?
Mono blocks with independent l-r channel capacitor bank boards (8@ 22,000 uf 63v 105c caps per channel).
This transformer:
AN-8425 - 800VA 25V Transformer - AnTek Products Corp
These boards:
Posh Audio - High Quality Audio Grade Components: Pass F5 Turbo V2 (4 Mosfet)
Of course I know the diy audio store has the official (to here) board version but these were a gift and I have them populated with good parts.
Thank you.
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It depends on your bias level. At more than 1amp bias per channel and with 4 channels I would want a bigger transformer.
Also, those PCB's have no cascode. I hope you don't plan on rail voltages much over 30V.
T1D … I'm assuming this is you moniker bcoz you have these speakers? Are you planning to use the F5 turbo v2s to power them? If so, I'll be very interested in how that went.
Regards,
Andrew
Hello!
Yes I have the T-1D's in a tri-amped system:
T-1D's l&r midrange --> Moscode 402Au
T-1C bass panels l&r (,100hz) Curl Vendetta x-over -> Moscode 402
Sequerra T-2 ribbon tweeters (the only pair made) --> Levinson ML-9
The F5 Turbo v2's will be two out put boards each mono block used in bridged mode.
The plan is to replace the ML-9 with the f5T v2's . I know the F5T's will sound much more neutral than the ML-9 which has the notorious Levinson upper mid-range suck out characteristic.
As to the transformer question I discovered after posting that I'd come to the x6 notes but had forgotten it. Indeed I do have idly reposing on the shelf 4 of the 800va Antec transformers. Yep, wife ever so gently threatened to equally gracefully drop them on my feet... just in case another gotta have it itch to order stuff exercised it's head!!
Truth be told as I have 8 output boards and 4 power supply boards soldered up I'll likely build 2 identical sets (4 dual output board mono blocks). Guess you could say that way if I dumb thumb something I might be backed up.... er well maybe!?
Thank you, everyone for your replies and guidance.
Now back to lurker mode.
32v.
By the way is there an easy way to make them cascoded (say pairing devices face to back then soldering into the original through bosses)? I think I once saw someplace here in one of these F5T forums someones picture of doing something similar with non cascode boards.
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Thank you.
I guess I did not express properly the amps I wish to build. By mono block I meant one chassis with 2 output boards bridge connected as Left channel, and another the same configuration for Right channel.
The power supplies will be Left and Right in a separate (third) chassis.
But yes, I had forgotten the x6 calc. though obviously once had decided to to use one of the 800va Antec transformers per channel.
Thank you.
OK, so all of the F5T boards are here, and I have transferred all parts to the new boards.
Since my target is 100 watts peak into 4 ohms, that's just a current of 5A through each side.
Wiring charts say that with 20 AWG wire, chassis wiring can pass up to 11 Amps. So 5 amps is a breeze, with plenty to spare.
Is there any reason for concern? Bear in mind that my boards are in series, with PS at one end and output at the other, along with the first stage board.
Since my target is 100 watts peak into 4 ohms, that's just a current of 5A through each side.
Wiring charts say that with 20 AWG wire, chassis wiring can pass up to 11 Amps. So 5 amps is a breeze, with plenty to spare.
Is there any reason for concern? Bear in mind that my boards are in series, with PS at one end and output at the other, along with the first stage board.
Wire is cheap. Go to the hardware store and get 5 spools of 16 ga. stranded wire in different colors for power and output wiring. You can't go wrong and won't have to worry about burning down your house. You can't have too much VA in your power transformer(s) or too big a wire gage.
WRT signal wire - 20 ga solid wire is good, but use your drill to twist it in pairs.
WRT signal wire - 20 ga solid wire is good, but use your drill to twist it in pairs.
My previous version used solid core house wiring at 14 AWG for all internal wiring, except RCA in.
To make the 14 awg fit, I found some solder cups that fit the gauge, but the boards had to be driled out to make the solder cups fit.
I did not do a great job of those connections. In hindsight, I should have just drilled out and connected the bare wire to the PCB.
This time, I was going to work within the limits of the boards.
To make the 14 awg fit, I found some solder cups that fit the gauge, but the boards had to be driled out to make the solder cups fit.
I did not do a great job of those connections. In hindsight, I should have just drilled out and connected the bare wire to the PCB.
This time, I was going to work within the limits of the boards.
In reading the F5Turbo manual, it suggests that peak output currents of 70 amps are possible from the V3 configuration.
I cannot imagine that sort of current being sensibly passed on 20 AWG wiring, which is the largest gauge the wiring that the boards can properly accommodate.
Does'nt this suggest that the F5Turbo boards, as built, can be dangerous? Or only dangerous when driven into very low loads? The manual says such current is available but does not specify the load.
Is the only way I can see around this problem to wire the F5T output boards must in parallel, not serial, else you need 8 AWG wiring.
In parallel, the wire gauge should be 12 AWG, as 12 AWG can carry 41 amps when used as chassis wiring.
If that is the case, then a 40 volt rail will need a transformer of over 2.8 Kva to deliver 70 amps.
Am I neglecting that the load should only be as low as the lowest speaker impedance we intend to encounter?
I cannot imagine that sort of current being sensibly passed on 20 AWG wiring, which is the largest gauge the wiring that the boards can properly accommodate.
Does'nt this suggest that the F5Turbo boards, as built, can be dangerous? Or only dangerous when driven into very low loads? The manual says such current is available but does not specify the load.
Is the only way I can see around this problem to wire the F5T output boards must in parallel, not serial, else you need 8 AWG wiring.
In parallel, the wire gauge should be 12 AWG, as 12 AWG can carry 41 amps when used as chassis wiring.
If that is the case, then a 40 volt rail will need a transformer of over 2.8 Kva to deliver 70 amps.
Am I neglecting that the load should only be as low as the lowest speaker impedance we intend to encounter?
70A is an expression of the absolute capability of the output stage. I doubt you will ever see that kind of current into any real speaker load. A 1 ohm load at 40V input voltage cannot draw more than 40A, and a 8 ohm nominal/4 ohm minimum will draw a max of 10A. It is unlikely you will ever see that kind of power output in any kind of listening situation.
I wouldn't worry about it. It's best to use 14-15AWG wire and simply terminate them properly. Spade lugs or bare wire crimps are a good option, if the board cannot accommodate the former, the latter will work.
I wouldn't worry about it. It's best to use 14-15AWG wire and simply terminate them properly. Spade lugs or bare wire crimps are a good option, if the board cannot accommodate the former, the latter will work.
Bare wire crimps? I cannot seem to find those that would fit a 14 awg wire into a 20 awg hole. And, they need a special crimp tool, or the connection can fail under high current.
I think I will use a male terminal pin soldered onto the board, as a locator.
The stranded wire will be pushed over the pin until it makes contact with the PCB, then soldered. I cannot think of a simpler way.
I think I will use a male terminal pin soldered onto the board, as a locator.
The stranded wire will be pushed over the pin until it makes contact with the PCB, then soldered. I cannot think of a simpler way.
The 14awg *must* touch the solder pad on the board, else that 22 awg wire is just too thin.
Um, no. Wire gauge doesn't actually determine how much current will go through a wire, just how hot it will get. A very short undersized wire will get enough heat-sinking from the wire around it to carry the current. It's the same way thermal reliefs on a PCB work.
Cheers,
Jeff.