Good grief... I love ya, bro... and I can't wait to hang out and listen to some tunes cranked to 11 on those magnificent Maggies and sip some good whiskey.
That's all.
what I wrote here is applicable fully to (bridging) F4:
see here, post #98 https://www.diyaudio.com/community/threads/the-marriage.390965/post-7154543
build Boo, with Edcor PC600:15K at input; that will be 5V/V gain
connect Iron Pre Bal in front of it, having 2V/V
sum is 10V/V gain, 20db exactly
pure Square Law bridged OS will run your Maggies with no sweat
if I didn't post Gerbers for said combo, just say
while we are at it, considering that I already posted Gerbers for Boo and Pooh, if Boyz want them for Store (more, the merrier, bigger headache), I have no objection
nota bene - I'm lazy to check data for Edcor - how much of distortion they'll have swinging 80Vpp, I can't say
but, whatever they distort, maybe you'll like that
NP in his design note ( prod_f4_man.pdf ) (*) mentioned how to do this:
"As a stereo amplifier with single-ended inputs and outputs, it will deliver up to 25 watts into 8 ohms with a damping factor of 40. It will do 50 watts into 4 ohms, and as a mono-block amplifier with parallel inputs and outputs, it will do about 100 watts into 2 ohms.
As a mono-block amplifier with balanced inputs and outputs the power output rating is 100 watts into 8 ohms at 1%, and the damping factor is 20." (**)
To fully drive the bridged F4 monos to 100 wpc, per my calculations, you will need ~28Vrms balanced.
To fully drive the F4 in single ended mode, you will need ~14Vrms.
Into 2 ohms. does the F4 runs out of current (per channel) so it needs to use both channels to drive the current necessary to keep up the voltage? So, it runs in parallel mode. (***)
I'm currently driving the F4 with a tube preamp in single ended mode very happily, but I followed ZM's idea to use what he considers "good" speakers... that is, 90db/w.. or more... at 6 ohms. So, they crank at "10.5" quite nice, I don't need '11" anymore.
(*) I suggest people copy his design notes into their own computers. They come in very handy. Same with ZM's and much of the stuff that is posted in these forums.
(**) You know, with the lower damping factor, I wonder if this is a good idea. One of the things I love about the combination of A2 and Maggies is the bottom end. Perhaps I'd be better off getting an F5Tv3?
(***) I recall one thread where I was curious about running an amp in parallel mode to achieve this.. Boy! I was roasted.
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no, build BA3, scaled to your needs; just my personal preference, never really being big fan of F5
it is great design, but I'm finding fact that its THD Spectra can be (set) anywhere in spectra extremes is unnecessary quality, again - my personal stance
The Maggies won't do 11..... but they will reach 10.5...
I quit drinking... well not quite. I just toned it down.. but not before I built a pretty nice collection of single malt scotches. If you come over we can crank Spinal Tap and I'll open the liquor cabinet... no problemo. ;-)
@zm: Yes, señor, you are correctomundo. The BA3 balanced will do it... but I love the sound of tubes... just got a newer preamp... so I'm still wondering if a solid state preamp can replace vacuum tubes. I'm still wondering if a fully passive autoformer with a TVC might not be the best for voltage amplification longer term. Mostly, I'm trying to avoid solid state in the front end, if I can.
For some, time is fleeting. To werker of wood and all carbon bases.
Go Zen, another brillant project for me!
Now I need a Bal BA3 FE. I can't keep up.
Go Zen, another brillant project for me!
Now I need a Bal BA3 FE. I can't keep up.
my preference is cleanest possible source(s) and pre, then solving all my Sugar needs with speakers and amp
vacuum or sand, it all sounds the same, when I'm building it
And, for all of the discussion... we're playing the SissySIT, non stop, in the caboose.... very happy.... the rest of the amps sit (pun!) on the luggage racks.
Tubes and SissySIT are magic, I tell ya.... so long as you follow ZM's advice to add "the Sugar" with the speakers.
Mind you, it's not the most accurate sound. I'm sure it has distortions, but it sounds fantastic. I keep thinking I ought to try the B1K in there on of these days. Keep it all thermionic in the front end.
Until perhaps we get the Glow In The Dark Heavy Iron... or is the BA3B a side track? Will it become an expensive unit by itself?
How about a simple Iron with SE to balanced transfer with switchable 6, 12, 24 db gain? All passive! Allow us to use our current SE amps that we love.
Tubes and SissySIT are magic, I tell ya.... so long as you follow ZM's advice to add "the Sugar" with the speakers.
Mind you, it's not the most accurate sound. I'm sure it has distortions, but it sounds fantastic. I keep thinking I ought to try the B1K in there on of these days. Keep it all thermionic in the front end.
Until perhaps we get the Glow In The Dark Heavy Iron... or is the BA3B a side track? Will it become an expensive unit by itself?
How about a simple Iron with SE to balanced transfer with switchable 6, 12, 24 db gain? All passive! Allow us to use our current SE amps that we love.
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Totally get it. We'll see where BAF winds up.
FWIW + a 1/2 eaten bag of chips...
It's really hard to go wrong with a BA-3. With your connections, you could have two built up for balanced monoblocks and set to your specific taste of honey when combined with your pre-amp of choice. Just sayin... With an Iron Pre in front of it ... yeah baby!
I haven't gotten around to setting mine up balanced. For my needs, SE is just groovy. I planned to go with mega mondo monster blocks and double this. It would take up another 4U/500 chassis when it's not really, really needed. So, it would be misused premium chassis space.
If I ever put my other set of boards into the chassis and run them balanced, I'll give you a shout. This one is playing now. Lower than spec'd rails with higher than spec'd bias current. THD set to roughly equal 2nd and 3rd. As Ferris might say... it is so choice, if you have the means, I highly recommend picking one up.
Enjoy the journey!
Edited to add - I say this knowing you already have Aleph 2s... So why not mix it up a bit?
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BA3 can be scaled enough without need to go bridged
ZM's correction of Silly ZM: while saying that I don't like F5 that much, I'm recommending an amp which FE is mini F5
go figure, boundaries of my silliness are Omni, as everything mine
ZM's correction of Silly ZM: while saying that I don't like F5 that much, I'm recommending an amp which FE is mini F5
go figure, boundaries of my silliness are Omni, as everything mine
But, it took years to get one of your builds in store. Point is,
you created a feeding frenzy.
you created a feeding frenzy.
no brainer
just build them all
don't forget to buy few more CJ anything, just in case and for giggles
just build them all
don't forget to buy few more CJ anything, just in case and for giggles
^ You were just looking for an excuse. It's not like anyone really had to convince you. 🙂
no brainer
just build them all
don't forget to buy few more CJ anything, just in case and for giggles
Hey, the CJ sounds awesome... I bought the first one in '89... did maintenance over the years and added the unobtanium in house teflon caps four years ago.
I just got a great deal on the ET3 which is slated for a factory visit for the teflon caps, vishay connectors, etc...
Always running Svetlanas or Sovtek in them... although the new one supposedly has a single, killer GE NOS tube in the line stage.
Sometimes, sometimes, you gotta pay for the IP. (Intellectual Property). So, I go the used route and make deals.
Meanwhile... get working, huh? All the time you spend posting, you could be doing the killer Heavy Iron preamp. I could arrange for a whole case of reds for you.
BTW, I keep looking for an audiophile quality USB cable... you got any ideas? Maybe with some impedance matching transformers? Iron USB so to speak.
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