"6-Channel Stereo"

jhoyt

Incomprehensible space llama
JHoyt's "6-Channel Stereo"

Yep, a 6-channel stereo (not Hexaphonic)!

I'll say it -- this is a very haphazard looking system. And yet it's not, as each part plays an important role. But the system is flexible, in that a certain amount of rolling, tweaking and experimenting is easily facilitated (drug references not intended!).

The system combines several major subsystems that may appear contradictory, but work together quite well. At the heart is... is... a home theater receiver! However, not just any HTR, but a Pioneer Elite SC-07. HDMI, full room correction, time/phase alignment, bass management, Wolfson DAC's, 7 ICEpower amps, and a GOOD preamp. HDMI is important to me, as I use a Toshiba Excite tablet as the main source. I can stream audio and video, which is important to my family. I use Google Play Music All Access as the streaming service of choice, and it works just fine, 320Kb and all that jazz. Basically I don't listen to CD's anymore, as the quality from GPMAA is virtually indistinguishable. And I'll take 10 million albums with a *slight* quality loss over 40 CD's that sound *slightly* better. Maybe. :yes:

The other main source is a gorgeous Denon DP-52M turntable, with the Panasonic strain-gage cartridge. The only issues I've had with this are a compliance compatibility issue, which I solved by adding mass to the headshell, and acoustic feedback. This is an interesting one, because I've never experience acoustic feedback before. Basically, I started playing a Dire Straits record (Love Over Gold) fairly loud, and even on the lead-in there was a horrendous low-frequency, high-amplitude rumble! I quickly cut playback and started again, this time paying close attention to what was happening. Lo and behold, I could see the cartridge "bouncing" in time with the rumble! In retrospect, I can see three things at play: 1...no TT isolation or suspension to speak of, just "rubber" feet; so I added the blocks of squishy foam underneath--it helps a little bit. 2...Bouncy old-house floors. 3...close proximity to the woofers. The takeaway is to play records, but keep the volume down; and it works fine now. I'd love to build an isolation platform or wall shelf, but those really aren't realistic right now.

Then there's the ubiquitous CD and BD/DVD players.

Downstream from the HTR things get even more interesting! I'm actually using the pre-outs, rather than the internal amps. The main line-level signal goes into an active crossover, then into two TPA3116 based amps, and from there into the top two speaker drivers. The subwoofer signal goes into an old PA amp, then into the bottom driver.

The speakers themselves are even a seeming hodge-podge of drivers, but they sound excellent. The "full-range" driver (actually it runs from about 500 Hz on up) is a 4" driver from a Yamaha HT-in-a-box set that was destined for the trash if I didn't rescue it! I wound up with 20 of these 4" drivers, and started playing around with them in various configurations. I discovered that they sounded phenomenal in an open-baffle setup, especially with a little EQ applied. The upper and lower woofers are the same, being 12" drivers from Peavey 2-way cabs. With the top woofer playing up to 500 Hz it sounds really good! Great lower midrange and upper bass. Of course these drivers don't naturally play very deep, so that's where more EQ and a quick cutoff point comes in: the lower woofer only plays up to 50 Hz. Since it is fed from the subwoofer output, I put a retired PA amp in place, rather than the TPA3116 amps that cover the rest of the range. This seems to work well, as I can get useable bass output into the 30's.

About the speakers themselves, they are an open-baffle design, but I added 12" sections of Sonotube (open at the end) around the woofers. This gives a longer path for the backwave, lowering the natural bass cutoff of the baffle. I'm intending on painting the baffles black...someday. My wife hasn't complained, and actually likes these more than some things I've drug in! :D

This is, by far, the best sounding setup I've had, and the flexibility is simply unmatched. I wish you all could come over and listen with me!

Enough babbling, now it's time for the starting lineup!

<<SOURCES >>
Turntable: Denon DP-52F with additional chassis damping
Cartridge: Panasonic EPS-451C Strain Gage, with custom interface circuit
Digital 1: Toshiba Excite 10" tablet, Google Play Music All Access, via HDMI
Digital 2: Sony DVP-NS900V, via SPDIF
Digital 3: Panasonic Blu-Ray, via HDMI
DAC: Wolfson WM8740 (in HTR)

<<NERVE CENTER>>
Pre/Pro: Pioneer Elite SC-07
Active Crossover: TDM CX24-4

<<AMPLIFICATION>>
FR: Sure TPA3116
MW: YJ TPA3116
SW: AB Precedent 400

<<SPEAKERS>>
FR: Yamaha (similar to Fostex FE103 in design)
MW/SW: Peavey 12"

<<CABLING>>
Digital: Monoprice, and whatever was on sale at Menards
Line Level: Homebrew, what else?
Speaker: Many strands of copper that do a darn good job of passing electrical current, 3-pair per speaker!
 
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Now those are some mean looking speakers. Would like to know more about the enclosures of the woofers. I can only imagine what your system sounds like. Seems to be a lot of members doing DIY speakers.

Hope they give you musical bliss! :music:
 
I'm dig'n the speakers. Would love to take a listen!
 
4Play, the woofer "enclosures" are simply open in the back. It's a variant on the "H-frame", or in this case, "U-frame" open baffle subwoofer design.
 
How do you like the sound from the SC07 ? How does it compare to anything you own that isn't an AVR?
 
One caveat is that I'm using the SC-07 as a pre/pro. The internal amps are supposed to be good, but I'm using the external TPA3116 amps instead. My impression of the sound is that it is very "modern", being open and transparent, even more than other separates I've run. And of course the flexibility is perfect for my setup.

It's it the "ultimate"? No. But for my financial investment, it's unmatched.
 
You are using an active crossover for the speakers? I have always thought it would be great fun to build a similar setup with active crossovers. Do you tune the speakers to the room?
 
The active crossover is great because it lets me try different speaker driver combinations, and I can set each driver level individually. I do tune the speakers to the room, but through the receiver's built-in EQ.
 
I use an older relative of your SC-07, a VSX-87TX (or something like that... along with a stupid remote, its name is about the only bad thing I have to say about it), but I use its amps as well.

I have lots of folks tell me that the amplifier sections in Pioneer Elite AVRs are quite good (there's a great review of the amp section on my AVR on Audioholics.com, and Jim Salk has told me that he really likes 'em too).

And, yeah, the phono sections in those AVRs are pretty darned good, but this past January, I added an external phono pre-amp (http://www.audioadvisor.com/prodinfo.asp?number=PAZPHOUSB#.VCqGqPldWSo - because I wanted to start archiving my vinyl). All I have to say about adding an external phono pre is this: WOW!!!!! It really brought my vinyl playback to life.

Highly recommended!
 
what are you using under the feet of your turntable?

It's a high-tech atmospheric-infused polymorphic hexahedral plastomer...

...okay, it's squares of closed-cell foam that came as packing material in something-or-other. It's the best (only?) vibration isolation material that I have. Does it work? a little. :D
 
Thanks! It is definitely unique--for better or for worse. :screwy:

Although yesterday I simplified it some, I pulled out the crossover, and am running the two 12" drivers in parallel, from the receiver's subwoofer output, through the Precedent 400A amp. It's crossed over internally in the receiver at 150 Hz. I'm not convinced it's better in total, but it is different. It does eliminate several capacitors and op-amps from the signal path, so there is an improvement there. But the handoff from woofers to full-range driver is not as smooth as I would like. Crossing over from a single 4" driver to twin 12" drivers isn't easy. I'm using a notch filter to help things out, and it seems to help.

The open baffle sounds SO good...
 
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