just had a look at the AN site and weirdly it says the PP = 9W and SE = 10W
There’s your mistake, right there. 
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I don’t know who winds Steve’s trannies for him (I suppose he might even do them himself ?) but he also builds and sells replica Quad IIs and Leak Stereo 20s and the transformers for those would need to be decent. The Stereo 20 has 20-odd dB of global NFB (i.e. wrapped around three stages) and it isn’t going to tolerate a poor OP transformer. The original amps were also spec’d from 20Hz to 20kHz. To be fair, both were UL-tapped though (the Quad II in an unusual way).
There’s no point in putting a huge amount of effort into a guitar amp transformer. Guitar amps sound the way they do precisely because they distort, after all. But it might be worth giving the trannies a try just to see what they can do.
Well, yes. Guitar amp transformers are generally not hifi.
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Fabulous work. What do they sound like?
I’m still tuning things so a little early to be definitive.
I‘m not finding it tiring to listen to plus there’s no much deep bass haven’t made measurements yet. I will know in a weeks time but l suspect the 200 400 hertz range has the nuls.
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Just a heads up for Modushop’s yearly Black Friday sale.
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Thought I’d post here rather than tat bazaar as it’s more diy based.
I have 4 jr149 aluminium cabinets from projects that never got finished. I think there’s enough wooden tops and bottoms to complete them. Some are the originals and some I made and veneered in rosewood. Have the metal bases but some are dented.
If anybody wants them to experiment. Make a modern version with new drivers or complete with new falcon drive units let me know and they’re yours gratis.
I do have 4 crossovers but was going to list them on eBay and try and recoup some money.
I can get some pictures as I start clearing the cupboard.
Top tip, save yourself a lot of time and effort by violently sticking knitting needles into your ears.
Shhh! I’m trying to give them away!
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they’ll bite your hand off over at PFM
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My next victims.
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Field coils arrived with no extra charges ,they’re a lot smaller than the Voxativ Fc’s which are now on their way to Oslo so these better be good 
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What voltage needs to be applied for the horn loaded implementation?
I did ask that question all done via current delivery each setting on the PSU relates to the 4 graphs the horn is 3 on the PSU settings
Each output is 25v
Drivers now loaded and settling in initial impressions fairly positive seem very smooth out of the box with no treble nasties unlike the short term Fostex drivers I tried .
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What’s the LF driver & what sort of frequency does the crossover happen at?
As with most of these types of drivers they certainly benefit from a few hours on them.
Got Bert’s BD15 bass drivers and think the Welborne active crossover was configured at 80Hz can’t find the original paperwork might be higher
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And starting with some free-air (no baffle) measurements.
After playing around with the various tweeters, trying out a 3uF cap on the BMS 4524/Seos12 combo gives me a lovely linear response, very impressed down to ~4kHz.
The initial 3 driver lineup (all at the same input level), Volt BM2500.4, Supravox 165GMF and the BMS 4524/Seos12 combo. Even with no baffle, looks like the 165GMF can get down towards the ~700Hz planned crossover point with no problem, have to have a play with some slim baffle shapes to see if I can tidy up that midrange response.
Supprised how close the 165GMF gets to the 4524 (with the 3uF cap) sensitivity wise. Opens up going passive on the midrange/tweeter (with a small L-Pad) to run of my Decware Zen in the future, then active on the mid-bass and woofer.
The plan is a ‘U’ shaped baffle for the BM2500.4 to bring that level up in the midbass so I can get down to ~150Hz to crossover to the bass driver (TBC).
These measurements were taken at 5cm from the driver, so sensitivity numbers while are accurate between drivers are not repersentative of 2.83V/1m etc.
I didn’t get a chance to start on the test baffles this week, see if I can make a start Wednesday. Priming the plaster and painting the new nursery have nudged it down the priority list!
That and getting to grips with VituxCAD for the crossovers…
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Now the baffles are here (the guy I used for the CNCing made an excellent job of them) I have started on working out exactly how I was going to mount the drivers - Because there was a round over on the rear cut thro the nut position I decided to 3d print a nut support clip - I’m tweaking the design of the clip as I go. Sixty hours printing for the clips and one twenty hours plus for the embellisher rings. I also knocked up a drill jig for the holes - Seems to all work OK.
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