Active multi amping.

And finally the decision was taken , after a discussion with my friend ex head engineer at the rep's shop we where working. The system should go a-x balanced all the way. B2302 simply accelerated the sequence.
Today , a sby day from work , I had plenty of time. So of I went from the couch to the office system that AU-X911DG was sitting and doing nothing last two months.
Unhooked it and took it to the living room and gave it a good cleaning on the outside. Then unhooked BA 3000 and hook up 911DG. Some quick adjustments and voila, midbass area cleaned up and live and rocking. Spend a couple of hours fiddling and tweaking . Fine sound , superb , fast , clean and clear. The itch though was still there.
I had the "ok go on from the missus " so after a quick nap at noon , I went and unhook the second 911DG, from her system. Took it to the living room too, cleaned it up work some switches a few times , AND unhook BA 2000 from the tweeters. Hook up 911DG on the tweeters and spend some time again fiddling and adjusting things here and there.
Finally sat down on the couch and listen to the music that was playing all the time from TIDAL HIFI . A few more level adjustments and voila, the perfect , or the best sound I have EVER heard from my new system with active multi amping.
Bass was already excellent , upper mid came to life with B2302 , mid bass became tighter and live with the 911DG and finally I got the BEST treble I have ever heard from my TWEETERS in this system with the addition of the second 911DG. Treble now is well defined , and distinct life like , you can tell whether a futsibal or a snare is playing or a single high hat. Real treble with nuances to explore. A nice sound with finesse and on the same time soft and gentle. I never Expected 911 being so nice on the treble although I was using it for a long time with my passive speakers.
What a ride!!.
The absolutely BEST sound I have ever heard , From my speakers with the active crossover.
 
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A few crappie photos from my cell phone.
 

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The blue and red lights between 911's are a pair of 120mm fans running in sandwich mode to cool down 911's
23's don't get those yet.
As you can barely see in photo no 2 , while 2301 is putting some power , 2302 is just almost idling. Not to mention 911's that are also idling , specially the tweeters driving one.
 
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John, Glad you continue to dial in the system. Why do you think the x-balanced approach delivered the improvements? Kinda sorry to see it move away from the definition series (selfishly) but sound trumps!
 
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And finally the decision was taken , after a discussion with my friend ex head engineer at the rep's shop we where working. The system should go a-x balanced all the way. B2302 simply accelerated the sequence.
Today , a sby day from work , I had plenty of time. So of I went from the couch to the office system that AU-X911DG was sitting and doing nothing last two months.
Unhooked it and took it to the living room and gave it a good cleaning on the outside. Then unhooked BA 3000 and hook up 911DG. Some quick adjustments and voila, midbass area cleaned up and live and rocking. Spend a couple of hours fiddling and tweaking . Fine sound , superb , fast , clean and clear. The itch though was still there.
I had the "ok go on from the missus " so after a quick nap at noon , I went and unhook the second 911DG, from her system. Took it to the living room too, cleaned it up work some switches a few times , AND unhook BA 2000 from the tweeters. Hook up 911DG on the tweeters and spend some time again fiddling and adjusting things here and there.
Finally sat down on the couch and listen to the music that was playing all the time from TIDAL HIFI . A few more level adjustments and voila, the perfect , or the best sound I have EVER heard from my new system with active multi amping.
Bass was already excellent , upper mid came to life with B2302 , mid bass became tighter and live with the 911DG and finally I got the BEST treble I have ever heard from my TWEETERS in this system with the addition of the second 911DG. Treble now is well defined , and distinct life like , you can tell whether a futsibal or a snare is playing or a single high hat. Real treble with nuances to explore. A nice sound with finesse and on the same time soft and gentle. I never Expected 911 being so nice on the treble although I was using it for a long time with my passive speakers.
What a ride!!.
The absolutely BEST sound I have ever heard , From my speakers with the active crossover.

Well done John! That's an impressive combo that you've got there.

John, Glad you continue to dial in the system. Why do you think the x-balanced approach delivered the improvements? Kinda sorry to see it move away from a the designer series (selfishly) but sound trumps!

Having had the benefit of personal experience with Sansui models from the early 70's up to their late-model Alphas, I think it comes down to the sonic benefits offered by the X-balanced topology.

I recall back-to-back comparison that I undertook between an AU-20000, BA/CA-F1 combo, and the AU-X701. The 20000 and BA/CA-F1 both sounded nice, and they were ultimately less resolving and obscured detail when compared to the X-balanced design. I find that after spending time listening to an X-balanced design, then going back to an earlier amp, the difference becomes more obvious (you are aware of the detail and timbral correctness that is being glossed-over).

I'd be interested to hear John's thoughts on this too.
 
John, Glad you continue to dial in the system. Why do you think the x-balanced approach delivered the improvements? Kinda sorry to see it move away from the definition series (selfishly) but sound trumps!

Dave, I think Pete Mac put it in an absolutely correct way. The sonics of DEFINITION SERIES are fine ,BUT , a-x balanced is far more superior. It's faster way better driven cause of the diamond differential ,with much more details , very resolving ,yet very accurate and soft. someone would expect more accuracy and resolution to tire ears and cause fatigue over time , but this is not the case here.
Sound comes more natural and soft like a said earlier , but not clinical. BA's tend to sound a bit clinical compared to alpha's. They sure sound slower (ba's) and a bit off timbre , fattening the sound.
Just that. If you can ever run a A-B test of a BA3K and a B2201 which is close to the BA's power , you'll find out .
Also you could compare BA5K to a B2301 or B2302 if you find one. The things you're gonna hear will mark you for ever. That is of course if you have a good analytical Pre amp to drive them and a pair of good analytical resolving speakers, second one is more crucial. Of course we are in the top of musical reproduction here and differences are few and delicate , but this is the last 5-10% of audio perfection . There's nothing more beyond this , except maybe some room treatments to trim the room acoustics , but this is a different story. Machine wise , this is the top one can ever get.
 
I'll honor you! I enjoy hearing you describe your experiences with the different hardware. I need to continue to develop my ear and experience before I could make meaningful distinctions. I have four systems in my den (BA-5k/CA-3k, B-209 also through the CA-3k, AU- 111 and AU-α907 Limited). I have them paired with A9's, JBL/Lancer 66, Klipsch Cornwall's & AR LST-2's. I enjoy them all and happily rotate my time between them. I do some A/B comparisons but mainly just enjoy them. Maybe when I have more time in life to enjoy them I will develop better discerning skills. Not complaining, life is pretty good and I have the good fortune to pursue the hobby and experience quality gear.
 
I'll honor you! I enjoy hearing you describe your experiences with the different hardware. I need to continue to develop my ear and experience before I could make meaningful distinctions. I have four systems in my den (BA-5k/CA-3k, B-209 also through the CA-3k, AU- 111 and AU-α907 Limited). I have them paired with A9's, JBL/Lancer 66, Klipsch Cornwall's & AR LST-2's. I enjoy them all and happily rotate my time between them. I do some A/B comparisons but mainly just enjoy them. Maybe when I have more time in life to enjoy them I will develop better discerning skills. Not complaining, life is pretty good and I have the good fortune to pursue the hobby and experience quality gear.


Ok here's what I want you to do. Do a direct comparison of 907 to ba5k-ca3k combo. Just make sure you level match them to put out the exact same power , like input a 1khz signal and output 2 or 3 watts out of both sets. It is crucial to level match them . After this, feed both sets with THE SAME signal from a cd player , that is the same l or r channel so both sets get the exact same signal, have the speakers placed next to each other , so the room interaction is minimum and have someone to alternate speakers on speakers off on each set .
This is the only way to directly compare two systems , specially amps.
Then you tell me what do you think and what you've found out from the comparison. I believe it's going to be very informative and interesting.
 
Sounds like a good exercise, unlikely to get to it until the weekend but will be enjoyable to see what differences I can discern. Thanks!
 
Well I spent the past hour going back and forth with the BA-5k and the AU-α907 Limited. Went through a variety of music I am very familiar with. I did find the more modern x-balanced technology superior (sharper highs, greater clarity) but I can't say the gap was huge. Both sound very good to my ear. I didn't swap over speakers to try to match but did do the real time "side by side/on-off" comparison with the same input and signal level. Was a neat experiment but in the end I am keeping both!
 
Ok you probably didn't have absolutely same levels.You sure had some differences that might have gone deeper, in some circumstances . The results vary with speakers, their placement in the room and so on. You would have experienced greater differences if you could have both speakers swapped each time. Also you would experience greater differences if you were running active multi amping like I do. There are many factors that contribute to the final outcome.
Never the less you sure are keeping both , that is quite clear.
 
I have to say I am running a Sansui CD-10 on my system which is currently in 3 Way Active. I have 2 BA-5000s one bridged-mono to each 15", BA-2000 running the 6.5" low-mids and then I swapped in an AU-717 that I rebuilt to Leestereo specs a few years back.. The AU-717 really opened up the detail on the upper mids and highs. The BA-2000 sounds great on the lower mids, vocals etc. I still have 2 BA-F1's, BA-3000, BA-2000 on my bench that I just simply havent had the time to finish rebuilding. Plan was to add one more amp to go full 4-way active. I love it so far its amazing! I did actually set a woofer on fire last week though... my 15" are rated 800WRMS and the BA-5000s are 600WRMS bridged/mono but something tells me any modern drivers rating is not as "real" as the vintage gears output is. Ordered a replacement, and less Jack and Coke while listening in the future. The amp is unharmed, I had to quickly remove the driver and run it out to the back patio to let it smolder out. Smoke was pouring out of the port on the speaker cabinet hahahah. KAZAAAP!
 
Now we be cooking! Glad you didn't burn the house down! I have been eyeing CD-10's in Japan, eventually will pull the cord on one. Looking forward to when I can spend more time on my gear and system creations.
 
Jomark911 turned me on to the CD-10 and vigman helped me procure it out of Japan a few years ago. I changed the power supply to US 120/60 and cleaned it up and it works like new. I love it! Best decision I have ever made.
 
Yeah Dave go on , get one , my friend in Mass bought a really nice one a week ago for 68000yen. Complete with the manual too. A very rare manual , even if it's in Japanese. Once you get it and convert your speakers to active there is no going back. Me and super will supply the tips and details to tune up the system.
 
I have to say I am running a Sansui CD-10 on my system which is currently in 3 Way Active. I have 2 BA-5000s one bridged-mono to each 15", BA-2000 running the 6.5" low-mids and then I swapped in an AU-717 that I rebuilt to Leestereo specs a few years back.. The AU-717 really opened up the detail on the upper mids and highs. The BA-2000 sounds great on the lower mids, vocals etc. I still have 2 BA-F1's, BA-3000, BA-2000 on my bench that I just simply havent had the time to finish rebuilding. Plan was to add one more amp to go full 4-way active. I love it so far its amazing! I did actually set a woofer on fire last week though... my 15" are rated 800WRMS and the BA-5000s are 600WRMS bridged/mono but something tells me any modern drivers rating is not as "real" as the vintage gears output is. Ordered a replacement, and less Jack and Coke while listening in the future. The amp is unharmed, I had to quickly remove the driver and run it out to the back patio to let it smolder out. Smoke was pouring out of the port on the speaker cabinet hahahah. KAZAAAP!

What size is the voice coil of the fried woofer?
Yeah go a little bit more conservative on Jack with coke, remember , that in a multi amping system the power is multiplied in each amp because the spectrum is divided in to sectors.
 
the VC is 63.5mm or 2.5" US
Oh I'm well aware of the sectors I have 600w RMS focused from 0-120 Hz and when it was acting soft, i just cranked up the gain some more until.... FIRE FIRE FIRE... roflmao... New woofer installed yesterday all is well again. I sent the other back under warranty... those guys will see this thing and wonder what on earth roflmao.

If i get crazy perhaps one day I will build a second cabinet and run dual 15" per channel to divide the power across 2 woofers per side. Because MOAR... :rockon:
 
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