Foolishly Bi-amping

[timbley]

I've got me a new pair of RF-7s, and I've been reading with interest many of the posts on bi-amping and bi-wiring. Since I have a Creek 60/60 Integrated amp, and a Parasound HCA-800II, I decided to do some experimenting.

When I first got the RF-7s I tried hooking them up to a cheap RCA surround reciever.

As I'm sure everyone would guess, it wasn't good.

So then I tried the Creek. Good.

Then I tried using the Creek as a pre-amp and the Parasound as the amp. Different, but not neccessarily better. Maybe even a little worse. Kind of thin and lacking in mid-range.

Then finally I tried the fool's bi-amping by hooking the tweeters to the Parasound and the woofers to the Creek's amp stage.

Wow!

There's no question about it. It's dramatically better than single amping.

So if this type of bi-amping is so foolish, why am I getting such great results?

The sound is much more lifelike and vivid. Imaging seems much deeper, more 3 dimensional. Vocals are easier to understand. Complex, loud passages don't go flat on me.

Interestingly, LP playback seems to benifit the most from this configuration. Dire Straits' Brothers in Arms sounds so good I can't hardly beleive my ears. FM radio and CD sound better too, though. I realize my amps aren't the greatest. Perhaps with a better amp fool's bi-amping would make a much less noticable difference?

[Deang]

It's hit or miss when you use different amps. You hit.

[Bill H.]

Timbley,

It's nice to see someone else using Creek Int Amp's.........were you saying its model # was 60/60 or something else? Glad you are enjoying the Bi-Amping results....

[timbley]

Yes, the Creek is a model 6060. I bought it about 10 years ago when I was on my first hifi frenzie. It's a nice 60 watt per channel that has the split/integrate button on the back so you can run it just as a pre amp or an amp, or as an integrated. For years I used it to power a pair of NHT Super Zeros that I had matched to a Yamaha subwoofer.

Cory Greenburg was writing for Stereophile back then, and had a series of articles on how to achieve affordable hi fidelity. He recommended the Super Zeros with speaker stands made of two cinder blocks stood on end. He also gave instructions on how to make a passive line level high pass filter for them instead of using the subwoofer's crossover circuit.

I did all his recommendations, except he didn't recommend the Yamaha sub. I just happened to have that around. I still have my special high pass patchcords that went from the integrated out jacks to the amp-in jacks on the Creek.

It ended up sounding pretty good, but I didn't really love it.

I almost sold the Creek recently. I had no interest in hifi anymore. I bought an HDTV and an RCA surround amp with some Radioshack surround speakers and center channel (featuring the amazing Linaum tweeter!) I was resigned to a cheap home theater system.

A young guy not even in his 20s came over to audition my Creek, We went to a couple hi end audio shops, bringing it with us to compare to newer amps. I guess he didn't like the 6060 since I haven't heard back from him. Hooked up to B&W speakers, I thought it sounded better than the NAD and Musical Fidelity integrateds. Well, maybe not the Musical Fidelity. But the amp that I think clearly bettered my 6060 was the new Creek A50i. My amp put enough edge on electric guitar to make both of us reach for the volume control. The A50i made us want to turn it up louder!

On big orchestra classical, I thought my Creek sounded particularly good on the B&Ws.

Since I've started this long story, I might as well finish by saying that I got back into hifi when, after years of prompting from my friend Gavin, I finally went over to his house and listened to his Klipschorns. I didn't know a thing about Klipsch speakers except that they used horns, and so could play very loud. Gavin used to set up sound systems for live events, so I figured he was just into that super loud, PA sound. I didn't expect to be impressed.

The Klipschorns suprised me with their size and looks. They looked like something from the 40s, which I guess they are! Gavin had them in a small room, with listening chairs right against the rear wall. I expected this might sound bright, perhaps even offensive. I braced myself for something very loud and harsh.

He turned on Joni Mitchell, and within two minutes I decided that I was listening to the best speakers I'd ever heard. Better than even the Wilson Watt-Puppies I had lusted over for years. And this was just playing on a Luxman CD player and reciever, with long runs of zip cord from his closet! As I expected, it was bright. But sooo clear. Incredibly dynamic! Not harsh at all. We had the volume cranked high enough that we had to almost yell at point blank range. Still I had no desire that he turn it down.

So I started learning about Klipsch speakers and wound up buying the RF7s just a few weeks later

I'm very happy with them, even if they're not quite as stunning sounding as the Klipschorns. They've got the big, clear, dynamic sound I thought I'd never be able to afford.

Bi-amped and playing vinyl, my gear seems to do them some justice. I'd love to hear what they do with good tubes, or the new 5350SE from Creek, or a SS from Monarchy. I'm also intrigued with Leo's Pio crossover upgrade, and with trying line level crossovers.

How good can it get?

[timbley]

In response to Dean G.

For once I got lucky!

What kind of Klipschorn you got? Discommodious?

[AndyKubicki]

Welcome to paradise! Congrats on your RF7s. Did you use any crosovers in your biamp experiment?

[timbley]

Thank you! I'm very happy to be here in Paradise.

I didn't use any crossovers. I just took off the jumper cables and hooked one amp to the tweets and the other to the woofs. I know this isn't the ideal way to do it.

I'd like to try an active, or perhaps line stage passive crossover at some point. But it sounds a bit complicated. For ideal results, I gather I'd need to get into the speakers and bypass the built in cross-overs, allowing the amps to directly control the drivers.

I've read on these forums that the crossover circuits have built in equalization and such that might be hard to mimick closely.

[Daddy Dee]

Timbley,

Why do you say it's foolish. If it works, sounds like it's a winner.

[timbley]

I called it foolish because some other threads referred to this type of bi-amping as "foolish." The reason given is that the full signal is being fed to both amps, so clipping happens at the same time as it would without the second amp.

It doesn't really seem foolish to me since it certainly sounds better than either amp working on it's own.

[timbley]

I'm now running two panasonic digital recievers to passively bi-amp my RF-7s. The improvement over a single amp is easily noticeable. The sound is clearer, more dynamic, and yet more relaxed at the same time. I especially appreciate the differences with harmonizing vocals or instruments. Sonority is heightened.

I do think you need two exactly matching amps though. I tried running an SA-XR25 with an SA-XR50, and I the differing signal processing results in slightly different delay times, which really has a destructive effect on the sound. I tested this idea by running the left speaker full range on one amp, and the right full range on the other. Stereo imaging was significantly blurred compared to using one amp to run both channels.

[InventiveAudio.com]

Timbley,

Try using FMODS for your crossover. The are inexpensive and work like a charm. They are also plug and play. You'll need to buy several cables but it really is an easy endeavor and you remove the risks of blowing a driver.

[Deang]

He's passively biamping -- making use of the crossovers in the speaker. Why would he need FMODS?

[InventiveAudio.com]

Dean: Timbley write: I didn't use any crossovers. I just took off the jumper cables and hooked one amp to the tweets and the other to the woofs. I know this isn't the ideal way to do it.

[DrWho]

hey timbley, what kind of room are you listening in?

[timbley]

Yes, I'm bi-amping passively, although going with F-mods and bypassing the speaker crossovers would be interesting, but complicated when I'm using digital inputs into the receivers. I'm not sure it's possible. A digital solution like the DEQX

http://www.deqx.com/index.html

looks very interesting. But since I'm using dolby digital and DTS signal sources frequently, it once again gets very complicated. We need an all in one solution for bi-amping home theater. For now, I'll just stick with passive.

BTW, I picked up an extra SA-XR50 today, so now I have two matching amps. This cleared up the delay problems I was having trying to use a 25 with a 50. So far, with 2 brand new 50s I'm not overly impressed, especially when listening through digital inputs. The sound is not as good as the old 25 was bi-amping through the surround channels using the 6.1 analog inputs. That was really spectacular. I was ready to tell the world that the RF-7 MUST be bi-amped or you're missing the boat.

The sound is much less compelling now, although pleasant enough and easy to listen too, and better than running a single XR50. With the new amps, the dynamics and separation aren't as good. Norah Jones' voice doesn't come to life and strike me right down to my soul. She just sounds sort of soft, warm and fuzzy. The bass seems a bit rubbery. Hopefully the amps just need to break in a bit. I have noticed that the sound from the analog inputs is considerably better than the digital, which isn't supposed to be the case with the Pannys. I've got my digital coax output from the denon 2200 split to both receivers. I wonder if that's a bad idea? Tomorrow I'll try using one optical and one coax to see if it makes any difference. Splitting the analog output from the Denon didn't seem to do anything bad at all.

Then there's the question of the Monster power center possibly being taxed to it's limit by two amps, thus limiting dynamics...

Too much to think about for now.

[timbley]

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On 9/7/2004 1:17:10 AM DrWho wrote:

hey timbley, what kind of room are you listening in?

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My listening room is about 16 x 14, and opens into a kitchen and down a hallway on one side, which causes some problems with stereo imaging. The ceiling is 7 1/2 feet, with asbestos (lucky me!) popcorn covering. I've got a hardwood floor with an 8x5 foot carpet in front and between the two speakers, which are located along the long wall, with a 34" widescreen CRT TV, a book case, and a kitchen cart converted to stereo rack in between. I've got bass absorption panels in the corners behind the speakers. I plan to get some more of those and put them where ever I can, since they actually look nice and really do make a noticeable improvement with the bass. It also helps the bass if I open all the windows and the sliding glass door (not practical in winter). My listening position is right up against the opposite wall, in front of the sliding glass door, on an old couch that's sagging in the middle where I sit all the time. The cat likes to sit there too, so I have to fight her for the spot.

It's actually a rather nice looking room. Guests always complement me on my cozy accomodations. Bit for a listening room, it generally sucks. Oh would I love to have a dedicated listening room.