Biwiring, Biamping

[jvlgato]

Someone (I have a pretty guess as to who it was) got behind my electrified fence, barbed/razor wire and broken glass set on top of a concrete wall in front of my A/V system, and broke the jumper cables on my speakers.

After being pissed and lecturing everyone about no one being allowed back there and turning up the current on the electrified fence, I figured it was a chance to biwire my speakers, which I'd thought about for a while, but never did. I've had all of one hour to listen last night, but it sure seems to sound better! Mostly I'm hearing better spatial resolution - each voice and instrument seems better separated from one another, vocals seem clearer, everything was more three dimensional, more depth, just a whole lot cleaner overall in the time realm - less smearing, more coherence, blah blah.

I always wonder if I just want to hear something after I've spend some money, but has anyone else biwired and heard improvements?

Is what I read about keeping the bass and mid/treble signals separated in their own cables so they don't interfere with each other a reasonable technical explanation, or just so much cable marketing mumbo jumbo?

How about going the next step to biamping? I'm curious, but it seems inherently wrong to have two different amps for a number of technical reasons.

[Grahame]

What happens to the crossover in all of this? (hint:

http://www.harbeth.co.uk/usergroup/showthread.php?297-Biwire-terminals-and-sound-differences

http://www.harbeth.co.uk/usergroup/showthread.php?1098-To-biwire-or-not-all-things-being-equal

http://forums.audioholics.com/forums/showthread.php?t=29665)

Edited April 14, 2011 by Grahame

[Dusty Chalk]

I used to biwire, but I convinced myself that it was mumbo jumbo. The biggest benefit was psychological -- I didn't have to worry about which speaker terminal to attach the wires to, and which driver to receive the inferior jumpered signal -- I used them both.

You can't tell electrons where to go, unless you introduce a demon (similar to Maxwell's) or a diode into the equation. That said, the whole thing about drivers (and associated circuitry, I.E. the crossover) and their associated amps "seeing" each other (impedance, back-EMF) does make a little bit more sense. But in my financial situation, I wouldn't do it unless I was doing something additional like putting an active crossover in front of the amps...and perhaps correcting for everything, like the Meridian or JH Audio systems do.

I think you should biamp the electrified fence.

[luvdunhill]

If amps sound different, then biamping must make a difference. For example, using a tube amp on a tweeter and solid state amp on the woofer in a two way.

[jp11801]

Active crossovers feeding a bi amp set up for the win, if you can bypass the internal passive crossover, or just spend the money on beer

[mrarroyo]

Lots of beer is a good thing!

[El_Doug]

biamping can make a substantial difference for the better - the soundstage improvement is simply incredible, I had no idea how badly some passive crossovers can mess with phase

biwiring is nothing more than lowering the effective gauge of the wire (2 wires are thicker than 1), and unless you are using ridiculously high gauge wire, or are running 50 foot speaker wire runs, this will not make a difference

[luvdunhill]

Biamping does nothing to change the phase of a crossover.

[Tyll Hertsens]

I think it sounds better for the same reasons star grounding is a good idea.

And I think you should piss on your fence and take fucking pictures.

[jvlgato]

Yeah, ok. So it's all psychosemantics (wow, spell check just turned that into 'pay hose antics').

That's cool. I had to do something, though, when the jumpers broke. Hey, maybe there's improvement from just replacing the random jumpers which came with these speakers, which I got used? Ok, I'm grasping at straws.

The tube for treble and SS for bass was what was on my mind, that sounds intriguing; the biamping with active crossover sounds really intriguing. But in the end, I'll probably opt for the more beer option. I'm happy with the sound, it's just audiophile masturbation.

Piss on the electric fence?! Ouch! I think I'd rather biamp it!

Pics? I'm terribly embarrassed about the state of my former man cave. It's as much a kid's playground as anything. There's a rear projection big screen TV on the back wall, wires and crap everywhere, boxes of stuff, kids toys, CD/DVDs everywhere ... I'm ashamed. I've tried to keep the acoustics as good as possible, but truly, it's not picture worthy here. I'd be permabanned for 'ugliest state of an audio room in HC.' If I really wanted to improve my speaker rig, it'd be to clean up the damn place ...

Thanks for setting me straight. And for the intriguing ideas.

Edited April 15, 2011 by jvlgato

[El_Doug]

Biamping does nothing to change the phase of a crossover.

the active crossovers before the amps are FAR better than the passive crossovers inside the speaker, including with regard to phase

[luvdunhill]

No. First order is the only option. Typically active are LR2 at the best and usually higher orders, not better at all in terms of phase.

[Grahame]

What about doing it all digitally? Data to the speaker, 1 DAC per driver. Model the ideal crossover in software/ implement in a DSP prior to the DAC, feed the DAC output direct to an amp optimized for the particular driver. No phase issues, an you can even add delay to time align the drivers.

What's that you say? Prior Art? http://www.meridian-audio.com/media/14218/dsp8000-ds2.pdf.

It'll never catch on, where are the endless tweaks, and the swapping of components in the hunt for Synergy

[luvdunhill]

This has it's own issues. Many drivers don't work well with slow slopes, so they don't integrate well, so you really need custom drivers I'd you go this route, something that isn't available to most of us.

[El_Doug]

No. First order is the only option. Typically active are LR2 at the best and usually higher orders, not better at all in terms of phase.

only in the analog domain. with a good dsp, you can make almost perfect time delays in all the right places

Edited April 15, 2011 by El_Doug

[luvdunhill]

only in the analog domain

Nope. Digital isn't some panacea, it has it's own share of issues. Time delay isn't the same as phase coherence, are you sure you understand what you're talking about?

Edited April 15, 2011 by luvdunhill

[jvlgato]

I think it sounds better for the same reasons star grounding is a good idea.

Tyll, I think that I misunderstood this part of your post the first time through. I don't know squat about technical design but thought I remembered a thread trashing star grounding, and thought you were agreeing with everyone that biwiring doesn't do much. But a quick Google search suggests that star grounding can help reduce ground loops and such, creating a blacker background. Is this what you were saying about biwiring,?

the active crossovers before the amps are FAR better than the passive crossovers inside the speaker, including with regard to phase

No. First order is the only option. Typically active are LR2 at the best and usually higher orders, not better at all in terms of phase.

Again, technically ignorant ... but one thing I remember about the Meadowlark speaker design principle was high quality, first order crossovers, and high quality Scanspeak drivers. Don't know if this was truth or just marketing speak ...

[luvdunhill]

It's the truth

[Dreadhead]

Nope. Digital isn't some panacea, it has it's own share of issues. Time delay isn't the same as phase coherence, are you sure you understand what you're talking about?

Are you? DSP can do both quite happily.

Edited April 15, 2011 by Dreadhead

[luvdunhill]

Are you? DSP can do both quite happily.

Sure it can, just like you can do both happily without DSP. It all comes down to implementation. People typically cite DSP as a cure all and have never sat down and actually done it to understand the challenges associated in getting it done right.

[Dreadhead]

Sure it can, just like you can do both happily without DSP. It all comes down to implementation. People typically cite DSP as a cure all and have never sat down and actually done it to understand the challenges associated in getting it done right.

You can not "control" the phase response of a passive filter (unless the laws of nature have changed since I studied RLC filters 10+ years ago). You can pick which response you want and what order etc but there are a lot of limits that just don't exist in the DSP space. Of course with the DSP you need to correct for the effects of the AD and DA on the phasing but it's pretty easy to do if the measurements are done.

I do agree though with your statement that DSP is not easy to do right but it can and has been done by lots of people already (eg. JH, Virtualizer, Nautilus, etc)

[luvdunhill]

I dont need to control phase, I just want it to be without nonlinearites.

Even if you needed to, which I argue you don't, there is an analog limitation with DSP: you cannot control impedance response with DSP. However, this is a very useful thing to control in speaker design.

[Tyll Hertsens]

I dont need to control phase, I just want it to be without nonlinearites.

It's my understanding that you don't get one without the other.

[luvdunhill]

Well, not really, Tyll.

I was using the word "control" in the same context as Dreadhead did. You can very much choose order which results in non-linearities without really caring what the resulting curve is, when building a passive crossover. You might not like what you have to do in terms of driver choice, or time alignment, but it's doable (btw, driver choice is perhaps even more critical in a DSP scenario, that's why the people that Dreadhead mentioned above contact out their driver design).

In a DSP scenario, like Dreadhead mentioned, this is harder. You have to actually control the curve itself in order to deal with the non linearities that the system itself inserts into the chain.

[Dusty Chalk]

Sure it can, just like you can do both happily without DSP. It all comes down to implementation. People typically cite DSP as a cure all and have never sat down and actually done it to understand the challenges associated in getting it done right.

Or, because they know that if DSP is done right, it can be a solution, but then make the incorrect leap that if it is done in DSP, then it's done right, which, at least with commercially available solutions, isn't always (or even usually) the case.

That said, I don't think it's fair to rule out DSP based on a few bad solutions, if good ones exist. I was just reading an article on all-band-pass filters that were designed to do exactly that -- correct phase.