I built a 4 conductor cable with speakon connectors, then I checked it to make sure I had continuity on all four poles. then I installed the speakon chassis connectors in the PSU and the Amp chassis. In every single case I was only able to confirm continuity in 3 of the 4 poles. I was literally tearing my hair out for 2 days trying to figure it out. 10 different speakon connectors - all failed. I wasn't going to risk using them so I went for the hard wired approach. I have an additional order of some more speakon chassis connectors arriving this week which I will also test. There may have been a manufacturing defect in the ones I had previously purchased. I have been working with electronics for over 25 years and building audio gear for over 20 years and I don't put mains electricity into anything until I have satisfied myself that there is proper and safe continuity across the entire application. Especially for the earthing side of the circuit. We may be fearless amp builders but we are not reckless.
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And yes, before anyone asks, hardwiring the PSU to the amp is very inconvenient, but it is electrically safe, and that is very important
There a lot of SpeakOn fakes, are those original? Check the packaging, newer have a hologram on them.
I never ever had any defective Neutrik connector.
Maybe you can post the exact model you have got?
https://www.neutrik.com/en/neutrik/...chassis-connectors/speakon-chassis-connectors
I never ever had any defective Neutrik connector.
Maybe you can post the exact model you have got?
https://www.neutrik.com/en/neutrik/...chassis-connectors/speakon-chassis-connectors
Yes, you must carry PE and circuit ground separately from PSU case to amp's case. PE connects to amp's case only, circuit ground you use for ground. Only in the PSU's case you connect both together, near the main power inlet. PSU chassis to PE as well and circuit ground via a circuit breaker to PE, you know.
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The Neutrik speakon chassis connectors arrived. Passed continuity checks. The others were clearly badly manufactured fakes. Be aware fellow DIYers
I was browsing through some Aleph J and Aleph 30 build threads on DIYaudio and I came across this: W12 dual transformer, dual secondary PSU from R Thatcher. So of course I've gone and purchased one. I am still game to try and get the PSU back inside the main chassis of my F5 turbo. The boards should be here in a few days. Here is a link to the DIYaudio thread where I read about it. Here is a link to the build guide for the PSU itself (it's a PDF download).
It will take me a couple of weeks to get all the parts needed (mostly the big caps) but then I'm going to build the PSU back into the 5u Chassis and see how we do. I'll keep the external PSU in reserve in case I can't get it to work.......
It will take me a couple of weeks to get all the parts needed (mostly the big caps) but then I'm going to build the PSU back into the 5u Chassis and see how we do. I'll keep the external PSU in reserve in case I can't get it to work.......
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What's impressive about Mr. Thatcher's design is that he includes an easy to assemble soft start board and snubber boards for the bridge rectifiers. It should make it really easy to build it up.
Thanks to Randy Thatcher. (rhthatcher)
Thanks to Randy Thatcher. (rhthatcher)
It's a dual mono PSU with separate PSU ground lines unlike the DIYAudio Universal PSU which has joined PSU ground lines tied together. It may be a distinction without a difference, but let's find out.
Hello dpogorman,
it is money! But if you build the F5T careful and hopefully will have no problems with hum / buzz...
perhaps you will never need another amp again?
The danger-scenario is, that you could get that involved to build many other projects from Mr. Pass, Wayne Colburn, ZM, ...
Go to an Audio-Shop and try to find an poweramp (ClassA) which sounds comparable good - check the price tag. Hmmmm 😵
I love my F5T- Monoblocks!
Enjoy the sound!
Dirk 😉
it is money! But if you build the F5T careful and hopefully will have no problems with hum / buzz...
perhaps you will never need another amp again?
The danger-scenario is, that you could get that involved to build many other projects from Mr. Pass, Wayne Colburn, ZM, ...
Go to an Audio-Shop and try to find an poweramp (ClassA) which sounds comparable good - check the price tag. Hmmmm 😵
I love my F5T- Monoblocks!
Enjoy the sound!
Dirk 😉
Dear Dirk,
I am already far down the rabbit hole! I've built the following: BA-3 (preamp) Bride of son of zen preamp (Currently using), Waynes 2018 Line stage, Waynes Pearl 2 Phono stage, BA-3 Power Amp, First watt F5 poweramp. B1 nutube preamp, B1 preamp, Aleph P1.7 preamp (never got it work quite right)
In addition I have boards and parts for the M2X poweramp, boards and parts for the Aleph J poweramp, Aleph 2 boards, Aleph 3 boards..... Boards for the IXYS F5.....
Lots of projects for the winter months ahead.
I am already far down the rabbit hole! I've built the following: BA-3 (preamp) Bride of son of zen preamp (Currently using), Waynes 2018 Line stage, Waynes Pearl 2 Phono stage, BA-3 Power Amp, First watt F5 poweramp. B1 nutube preamp, B1 preamp, Aleph P1.7 preamp (never got it work quite right)
In addition I have boards and parts for the M2X poweramp, boards and parts for the Aleph J poweramp, Aleph 2 boards, Aleph 3 boards..... Boards for the IXYS F5.....
Lots of projects for the winter months ahead.
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Progress update: I've stuffed and soldered all the major components for the W12 PSU. Photos included.
From Left to Right: Setting up the board for work, R1-16 installed, R17-20 installed, LED resistors installed, LEDs installed, Power capacitors installed.
I have a couple of other components on order so I'll be stopping here for now.
From Left to Right: Setting up the board for work, R1-16 installed, R17-20 installed, LED resistors installed, LEDs installed, Power capacitors installed.
I have a couple of other components on order so I'll be stopping here for now.
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I went with 15,000uF for the capacitors. It gives a total of 180,000uF for the PSU. I think that should be adequate.
It may be an apocryphal myth, but I read once where a Rolls Royce engineer was asked how much power a Rolls Royce car had and his response was 'it is adequate'. I think that sums up this PSU!
It may be an apocryphal myth, but I read once where a Rolls Royce engineer was asked how much power a Rolls Royce car had and his response was 'it is adequate'. I think that sums up this PSU!
Just to finish and for Dirk's amusement here is a photo of my shelf of glorious previous projects...... Have a laugh.
B1 preamp, Ba Nutube preamp, Aleph P1.7, Aleph 3, various power supply experiments created for the Pearl 2 psu, the aleph P1.7 psu, many iterations of stepped attenuators, relay controlled input boards, there is even a couple of PSUs for the Bride of Son of Zen, At least 3 experimental relay controlled volume controls, both balanced and single ended. There are some other audio experiments in there but I can't remember what they are right now.
B1 preamp, Ba Nutube preamp, Aleph P1.7, Aleph 3, various power supply experiments created for the Pearl 2 psu, the aleph P1.7 psu, many iterations of stepped attenuators, relay controlled input boards, there is even a couple of PSUs for the Bride of Son of Zen, At least 3 experimental relay controlled volume controls, both balanced and single ended. There are some other audio experiments in there but I can't remember what they are right now.
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Hey guys, it’s been a while since these post were up. It’s been really busy but I’d like to report back. I picked up some 1Nf caps and soldered them across R7 & R10 and so far the bias has stabilized big time. In fact I’m finally able to set the offset extremely close to 0 and it holds. I’m going to let It run again all day Saturday. If it holds steady, I‘ll get it connected back up to use until I’m ready to convert it into a V3 monoblock this fall. Thank you everyone for the help.