Post Fri Oct 21, 2011 10:25 pm

Sisu1a's Mutant 4.4 circa Oct 2011 (non Carver)

My Twin Stereo/HT Thing, as of Oct 2011:

AMPS:
Jolida SJ502 (two units, one modded to accept EL34's)
Acurus A250
NAD 2400
Outlaw ICBM-1 (two units)

PREAMPS:
WANTED: Carver C-1 or C-11(TWO needed, but I'm being a cheapass or else I'd just grab any of the many available... PAGING ANTONIO! I WANT YOUR C-1!)

PROCESSOR:
Integra DTR 7.4 (a receiver actually, but I only use it for a processor [a hot processor] and think of it as spare amp channels for 'emergencies')

SPEAKERS:
Mains: Ohm 2XO + two Hsu TN1220's
Rears: Magnepan MC1's + two *Baby TN's

SOURCES:
Sony DVP-875DVP
Crappy ass computer>USB>optical

VISUALS:
Optoma EP751 projector
Greywolf II fixed screen, 120"

How I run it:

My mains, which like some here are also my 2ch rig for 'serious listening'. The modded **Jolida (=C= EL34, NOS Mullard CV8024, reissue Mullard 7025) runs the Ohm 2X0's, the Acurus A250 powers the TN's and the ***Outlaw ICBM is crossing them (80Hz; for now...), with the Integra doing preamp/DAC duty. Simple enough...

My rears, which probably unlike most here, I consider to be my other 2ch rig, and to my surprise get more exclusive use than I ever thought they would before bi-amping them. The stock Jolida (junk tubes for now) runs the Maggies, and the NAD runs the Baby TN's, using the other ***ICBM-1 to cross them, but these are x'd and 100Hz to keep everything happy. I'm sure everyone has heard this cliche', but my rears really do sound like giant headphones when I have good amps on them. There actually is some music that I do listen to in the sacrilegious mode of 'All CH Stereo' and here's why. Many bands I've seen have also speakers behind me, so it sounds closer to what it did when I was there (been to hundreds shows, maybe past the thousand mark by now since I still go...). I can also make them disappear (in the good way) into the 2ch soundfield when adjusted correct, which is not distracting at all and gets hard to tell if they're on or off without checking, but this may also be because the Maggies are dipoles and the subs are omnis. It is not my common listening mode, but it does happen, especially when I need to do things around the house. Major sound quality improvement for extreme off-axis listening, like being in the kitchen. Sometimes for latenight mode I run the rears by themselves, mainly because I live in an apartment and those don't share a wall with the neighbor.

It really is two 2ch systems back to back, especially once they can be run completely independent of each other to decent effect. For now they are tethered together by the Integra, which actually does an OK job of processing. When using it in 2ch mode, it has a nice soundfield option called 'Pure Audio' that shuts down power to all the other circuitry (including the display) not being used and bypasses any tone controls/eq's/etc and actually sounds pretty nice for music considering it's just a HT receiver. I have it set to 'subwoofer off', which redirects any bass from the .1 (if present) to the mains and also have the center switched off (phantom center), which does the same rerouting of 5.1 sources -hence my designation of 4.4 since I have 4 discrete channels, each with their own sub, but this may be a misnomenclature since the .4 doesn't exist like that at the source level. The Ohm's don't need any help whatsoever to achieve what even a pretty decent center speaker hopes to, accomplish although I will admit to having a weak spot for the Magnepan CC3 should one find it's way to me...

INTO THE FUTURE:

Moving forward I'm looking to add the two Carver C-1's or C-11's, one front and one back, so I can hook a DAC/etc directly to them for better 2ch listening. With all the inputs and outputs on those units, I would have two truly independent 2ch systems that can also be used for HT when I select the input I have the processor's preouts hooked to. No idea what processor I'll go for next, perhaps a Sunfire, maybe an Outlaw, maybe Emotiva. The NAD 2400 will at some point be replaced with another Acurus A250, and the Jolida's will be occasionally modded and brought up to higher specs as time goes on, maybe even a triode switch. I plan on small Acurus mods as well as eventually attempting the BillD mods to the C-1's/11's. The Sony will eventually give way to an Oppo 93, and there will be other source upgrades too, although not in any big hurry due to financial limitations.

-Paul



*Baby TN's are what I call the 2/3 scale TN1220's I made using a couple spare M&K drivers some 8" sonotubes and a gang of lead; construction detailed here:
http://forum.hsuresearch.com/showthread.php?t=95023

**The Jolida 502 and 302 are actually the same amp, just with different value resistors in the bias circuit, a 20k and a 12k respectively. By using a value in between, it allows enough bias range to use EL34/KT77's or 6550/KT88's. I soldered some 56k's I had laying around onto the 20k's parallel and now have 14.7ishK. Factory recommends 13.3K, I've seen others get away with it at 16K...

***The ICBM-1 is an active x-over that uses 12dB Butterworth for the high pass -not ideal- but since it's 6ch unit and I'm only using 2 of them I cascaded 2 unused channels and achieve the 24dB Linkwitz/Rily arrangement. Low pass is user selectable at 12/36dB, with discrete L/R sub outs. With it's adjustable fixed-point x-over settings it is quite a flexible tool for those of us without XLR's on our gear who want to bi-amp. note: Outlaw is working on the ICBM-2, which will have XLR's, but you didn't hear that from me cause I ain't one to gossip!