OK, but HOW does it sound? BA3 Bal / Bridged F4s vs XA252 MOSFET

Tony put away the Hoff to listen to some classic Sex Pistols - nice!

Also for wires - use Belden or Mogami and save $$$$$$$$$$$$$$ to buy all the Lagunitas or Racer 5 you want.

Belden? I only use Canare or Mogami!. I might have to do a comparison now..... Ay!

I always have the Hoff CD next to DAC.... The polycarbonate keeps the electrons aligned.
 
Ask Randy about those.... I know he knows them.

I am still curious about the F5Tv3.

The older Alephs are very good sounding. I think the A2 is likely the inherently most powerful amp I got that doesn't need tricks to put out lots of power. But, it is a pair of big mommas.... 5U x 400. It drives the Maggies with real aplomb.

Midrange wise, though, the Sissy and 252 sound better.
 
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100 W class A mono is always pair of big mommas. No skiny milfs in that department. 😀

F5Turbo v3 should be theoretically craziest amp with feedback and highest current delivery....I will make monos without turbo diodes, but with 6 output pairs to stay on high current side of things...
 
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I can say I've built F5 Turbo V3, Aleph 2, Aleph 60, etc. But in my home Tannoy 12" monitors are the low efficiency speakers, and I'm running horns on the big system. So I can't comment on the 100W amps the way you can with the Maggies, for example. I simply don't need the power, so I don't push them to the limits. In my home, the XA252 in MOS, SET, and SIT variations all have absolutely incredible bass performance for depth, control, and speed. But I'm not asking the Tannoys or JBL Hartsfield clones to work very hard, either. I've also never had an F4 or BA3, so I can't make that comparison, either. For my taste I will always have some flavor of Aleph, a SissySIT, and a variation of XA252/Plethora of Pinjatas in my home. Other builds will come and go, but these will stay forever. That's my personal taste.

The F5 Turbo V3's were built for a guy I've known for decades, and they are his main amps. He has had factory Aleph 1.2's, Bryston 200W+ monblocks, and many many more. He loves the F5's for transparency and power. And he liked them even more when we did some turning and fine tuning with the P3 pot. He was also borrowing a SissySIT for quite some time, and he would love a 50-100W SIT type amp. The SIT sings a siren song for sure. I assume it's a common enough request to figure out the big power SIT amp.
 
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De syren canticvm biggvs dickvs 454 SIT nam cum macho 252 SIT non sufficit

The complementary is...

High Efficiency Magnepans.

Take your choice.... which one will make in our lifetimes?

...

I've heard the Tannoy Sterlings being driven by a 300B tube amp... They sounded very immediate and dynamic. You could hear the singer's lips smacking as she was singing, you could hear her breathing by the mike. Extremely revealing indeed. And didn't seem to need much power. But, but.... I like how the Maggies fill the room. I guess it's just a preference.

In my mind, the sound of the Tannoys is like a British sitting room filled with red velvet in a rainy Saturday afternoon while drinking some ruby port... while the Maggies are like a sun filled mid century modern house overlooking the Pacific/pool on a Sunday while drinking pitchers of margaritas.

Which, sort of brings up another question.... which speakers are best to HEAR the sound of the components. The Maggies are good at revealing the sound difference of amps when they are being stressed - meaning when they are really putting out their first 10/100 watts. Otherwise, they superimpose their own sound to the presentation.

OTOH, my little Acoustic Energy AE1s are champs at detailing every little wart of the front end and amps... except for the deep bass.

What kind of speakers would an amp designer use?
 
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My wife would kill me.... speakers? In Woodland Hills.... Vide the JBL Metregon - with updated Tannoy 12" woofers..

https://www.ebay.com/itm/2766590106...customid=1bbbcd6e-de72-11ef-a7db-663432383635

Will the Sissy drive these?

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^ That pretty much sums up what I hear... the soundstage gets pushed back and there less "resonance" to the instruments....

But the bass.... OMG.... I've never heard Maggie bass SLAM like that.

Maybe, well, just maybe, I just LOVE how it sounds?

Thinking about such lines... would then an bridged amp with sufficient current add this? Bridged XA252 MOS? Bridged XA252 SIT?
 
I am not familiar with those amplifiers, but in general you should use an amplifier capable of putting 10A peaks into 4 ohms (not bridged). Suitable amplifiers will have low output impedance.

Since you like the sound, you can mimic the effect by adding a resistor in series with each speaker.
Ed
 
Will the Sissy drive these?

more than certainly

though, as I just replied in PM:

I was thinking in one period to build one for myself, and then realized - if I have anyone to ask did he ever heard those, it's Pa

His reply was - nice overall, but if you like to have bass, avoid

though, as cornerstone (sort of) it's ubernice

(Pa, Omnieverything, so Omniknowing)

edit: as I just had stint of my multiphase sleep, and coffee didn't yet kick in, didn't realized size, so thinking that's Paragon; for Metregon even more applicable bass remark; my usual MLTL cabs for 12" Tann are sprinting in circles around that nice furniture
not because I'm smart (er than guys constructing all that Yore stuff), simply because I was smart enough to find MJ King's software, half a century 60-70 years later
 
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If putting a resistor in series with an amp output makes for better bass, that could be. Maybe the amp needs to see a bit higher (real) load impedance to output FR evenly, or to distort a little more evenly across the frequency band, whatever it is that gives an impression of petter bass. I mean, if you try and it works, there has to be something kinda interesting going on.
 
^ trick known from Yore, some (tube) amps were even equipped with pot controlling Rout

If that's the case, maybe I ought to try hunting down a, ARC D125 or a VT100. I could play with the outputs.... they go 4, 8 and 16 ohms.

And, I've never hooked up the D70-II to the Maggies.... Maybe I should?

I remember reading that Magnepan and ARC sort of grew up together and were shown at shows together for many years. Indeed, the guy from whom I bought my D70-II had Maggies III and he moved to a D125 which he said played fantastic with the speakers.
 
Zen is right in that the lack of damping factor in the balanced amps compared to the XA252 gives the balanced amps a fuller sound with a higher quantity of perceptible bass. There is very little resistance in the output stage of the XA252. The same with the XA25. I don't remember the exact damping factor of the XA25 but I think it is something crazy like 500 where the XA30.8 is something like 150. Don't quite me on this... I mention the XA25 because it has a similar output stage to the XA252.

This extra damping factor in the XA252 offers a lot of control and results in a very fast bass. It is also sometimes so clean that the bass is less apparent... Is this better? Well, I think it is up to the individual. You seem to be enjoying the sound of a bridged amp with no feedback...

The bass of these balanced amps with lots of mosfets tends to flow more into the soundstage which can be really nice.

Now adding negative feedback to the BA3 (not a plug and play option) should tighten the bass up a bit as it will also increase the damping factor. So if you added a feedback circuit, the sound would probably become less lush, have tighter imaging, a bit less perceptible but tighter bass and be a bit more articulate. Also it could be less holographic. I haven't done this experiment personally with the BA-3 but that is my suspicion.

Now that I think of it, the BA-3 does have three gain stages as well. If you want to try a different sound, replace the mosfets in the BA3 with 2SJ313/K2013 mosfets. Their VGS is lower so you will want to reduce the trimmer pot resistance down to 0 and then reset the bias. However, they tend to have pretty great bass. They are also fairly detailed with good texture in the imaging if implemented right.

Your XA252 is a very cool amp!
 
There is something y'all are ignoring from my comments.

Normal bass:

Iron -> SE -> BA3 -> Bal -> bridged F4s
Iron ----------------> Bal -> XA252

Rich bass:

Iron -> Bal -> BA3 -> Bal -> bridged F4s

It's ONLY when I use the balanced connection between the Iron Pre and the BA3 then I get the fuller bass. I've heard this character with three pairs of speakers. Elac BS41-BK, AN AN-K/LX and Maggie 1.7. It made the little speakers sound much fuller, the larger bookshelves sound perhaps a bit too rich but it simply complemented the bass slam of the Maggies.

I never changed the wiring between the BA3 and the F4s.

The end result though sounds very pleasant over the Maggies. Although it's too easy to get carried away and overdrive the Maggie panels.

Perhaps it's how the BA3 was wired. I need to send a text... I know the other pair of BA3 and bridged F4s are feeding a pair of LRSs in a rather small room and he's loving it.

In the meantime, I got the Maggies on the bridged amps. It's like the difference between plain vanilla and praline pecan ice cream. If it's distortion, well, don't tell ASR, just pass me another bowl of that delicious ice cream.
 
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