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Singapore HiFi Stereo Equipment discussion forum => HiFi Audio Equipment Discussion => Topic started by: watchdog on August 20, 2016, 11:20:32 PM

Title: Bi-wiring - Yea or nay
Post by: watchdog on August 20, 2016, 11:20:32 PM
Hi Guys,

Care to share your personal experiences with bi-wiring ?

Do you think bi-wiring brings a significant difference ? OR

Do you feel that spending the extra money on better speaker cables is a better investment ?

Anybody thinks that you can get the benefits of bi-wiring by replacing those horrible jumper links with a proper set of wire jumpers ?

If you don't believe in bi-wiring, did you get better effects connecting your cables to the tweeter terminals or woofer terminals ?
Title: Re: Bi-wiring - Yea or nay
Post by: OnePunch on August 21, 2016, 09:30:19 AM
Never have experience with bi-wiring as all my speakers in the past is single wiring configuration.

Why speakers makers make bi post anyway?  Any benefits?
Title: Re: Bi-wiring - Yea or nay
Post by: jb on August 21, 2016, 10:25:47 AM
My personal opinion, if you assume the speaker cable as transmission line with inductance, resistance and capacitance. Then using a bi-wiring connection will allow separate connection path for bass woofer and tweeter, so it allow you to tune the bass and high frequency separate which I think is better option. Some may use copper wire for the bass woofer and using silver wire for the tweeter. But all these were system dependent.

Personally I have been using bi-wire since my speaker allow bi post, changing different speaker cable to drive the bass woofer or tweeter do make the difference in sound. But finally I opted for the Nordost bi -wire cable as is more cost effective and less messy in the room.
Title: Re: Bi-wiring - Yea or nay
Post by: watchdog on August 21, 2016, 03:36:11 PM
Never have experience with bi-wiring as all my speakers in the past is single wiring configuration.

Why speakers makers make bi post anyway?  Any benefits?

In theory, this allows reduced interaction between the bass and high frequency units. Apart from the benefits of tuning using separate cables already mentioned by jb, you can also bi-amp, i.e. use separate amplifiers for the high frequency and low frequency units.

I asked a very prominent designer once on his thoughts on bi-wiring (his speakers use bi-wiring terminals). His answer was interesting ... he said he provides this because this is demanded by the market, not because of any technical benefits.

On a good day, bi-wiring brings about gains in transparency, and separation. On a bad day, the two drive units end up sounding disjointed and uncoherent. This results seems to me to be quite speaker dependent.
Title: Re: Bi-wiring - Yea or nay
Post by: shadowmoses on October 06, 2016, 11:14:14 PM
I personally like the idea of bi-wiring though its not steeped in any logical basis other than it looks cool (this is not logical too), and potentially allows you to bi-amp in the future.

Interestingly though when I started looking for hi-end speakers, I struggled to find companies/speakers that provided bi-wiring options. Many of my shortlisted speakers only had a single pair of binding posts. Some of my options included Rockport, Verity, Vivid Giya etc. The most common explanation was that the designer had already designed the speakers, in particular the crossovers, optimally with just single-wire and found that bi-wiring had no benefit.

So... no choice, just go with single wire  ;D
Title: Re: Bi-wiring - Yea or nay
Post by: Wizardofoz on October 07, 2016, 01:17:01 AM
All my main stereo speakers are using active crossovers before the amps, and drivers are direct connected to the amps outputs (no internal crossovers) so each driver has its own amp and speaker cable too. This is by design and the guy who designs this stuff is half of the pair who probably are the most famous speaker crossovers designers Linkwitz/Riley www.linkwitzlab.com

2 of my speakers use 4 amps per speaker and another 2 sets use 2 amps per speaker.

I have Orion v3.3.1, Pluto 2.1, LX521 reference and latest is LXmini with subs to be added (another 2-4 channels)
Title: Re: Bi-wiring - Yea or nay
Post by: watchdog on October 07, 2016, 01:01:17 PM
I personally like the idea of bi-wiring though its not steeped in any logical basis other than it looks cool (this is not logical too), and potentially allows you to bi-amp in the future.

Interestingly though when I started looking for hi-end speakers, I struggled to find companies/speakers that provided bi-wiring options. Many of my shortlisted speakers only had a single pair of binding posts. Some of my options included Rockport, Verity, Vivid Giya etc. The most common explanation was that the designer had already designed the speakers, in particular the crossovers, optimally with just single-wire and found that bi-wiring had no benefit.

So... no choice, just go with single wire  ;D

In the case of Vivid, their speakers have biwire terminals.
Title: Re: Bi-wiring - Yea or nay
Post by: jb on October 08, 2016, 09:06:30 AM
I personally like the idea of bi-wiring though its not steeped in any logical basis other than it looks cool (this is not logical too), and potentially allows you to bi-amp in the future.

Interestingly though when I started looking for hi-end speakers, I struggled to find companies/speakers that provided bi-wiring options. Many of my shortlisted speakers only had a single pair of binding posts. Some of my options included Rockport, Verity, Vivid Giya etc. The most common explanation was that the designer had already designed the speakers, in particular the crossovers, optimally with just single-wire and found that bi-wiring had no benefit.

So... no choice, just go with single wire  ;D

I think some highend speaker designer may think their design optimization is the best using their setup system. But in most case , every user will have different preamp, power amp or cdp or cable, you may not get what they heard in the manufacturing sound room. I would prefer them to have the bi wire option for user as it will not degrade their speaker sound, but allow user experiment with other cable option.
Title: Re: Bi-wiring - Yea or nay
Post by: sydney1128 on October 08, 2016, 05:09:20 PM
If speakers can only drive by single amp, then we need to find suitable power amp that have enough power and match well.
If doesn't match well, then we may have to either change speaker or power amp.

Bi-amp or bi-wires seem to allow us to "change/tweak" the sound with either speaker cable or amps.

But what can we adjust if there are two different loudness level from two different power amps?
How shall we adjust and tweak in order to get both tweeters and bass drivers sound "coherent" with same loudness level?

Reason for asking this is I have two amps that has different output impedance and am planning to change to a speaker that can play with bi-amp.
Any suggestions?
Title: Re: Bi-wiring - Yea or nay
Post by: jb on October 10, 2016, 07:30:41 PM
You can do vertical or horizontal bi amp connection as shown attached... but i see no way to control the loudness of the woofer or tweeter for coherent unless you have two set of preamp to control the power amp volume.
Title: Re: Bi-wiring - Yea or nay
Post by: WCK on October 17, 2016, 09:32:27 AM
Never have experience with bi-wiring as all my speakers in the past is single wiring configuration.

Why speakers makers make bi post anyway?  Any benefits?

In theory, this allows reduced interaction between the bass and high frequency units. Apart from the benefits of tuning using separate cables already mentioned by jb, you can also bi-amp, i.e. use separate amplifiers for the high frequency and low frequency units.

I asked a very prominent designer once on his thoughts on bi-wiring (his speakers use bi-wiring terminals). His answer was interesting ... he said he provides this because this is demanded by the market, not because of any technical benefits.

On a good day, bi-wiring brings about gains in transparency, and separation. On a bad day, the two drive units end up sounding disjointed and uncoherent. This results seems to me to be quite speaker dependent.

If you ask the repair technician (or if you know how to read schematics) about how the AB speaker switch works in any amp, they will tell you Spkr-A is driven by the same amplifier components as Spkr-B.

Hence if you use Spkr-B as well as Spkr-A, you basically double your resistance profile to each spkr - reason why the manufacturers manual always advise regarding speaker impedence if using both A&B at the same time. This is before you include the resistance from the 2nd set of speaker cabling for Spkr-B.
Title: Re: Bi-wiring - Yea or nay
Post by: jb on October 17, 2016, 12:38:26 PM
yes, the two set of speaker terminals are connected to the same amplifier output in parallel. For most well design speaker cable the resistance is below 0.001 Ohm so is a small fraction of the actual speaker impedance of 4 or 8 Ohm. Thus I believe the benefit of bi wiring is from the extra inductance or capacitance of the second set of speaker cable that improve the sound and also isolated path of current driving woofer and tweeter circuit.
Title: Re: Bi-wiring - Yea or nay
Post by: WCK on October 18, 2016, 09:38:43 AM
yes, the two set of speaker terminals are connected to the same amplifier output in parallel. For most well design speaker cable the resistance is below 0.001 Ohm so is a small fraction of the actual speaker impedance of 4 or 8 Ohm. Thus I believe the benefit of bi wiring is from the extra inductance or capacitance of the second set of speaker cable that improve the sound and also isolated path of current driving woofer and tweeter circuit.

Since you have the SPICE tool, curious to know if it show the above? Only know of NAIM gear which have their own NACA requirement to induce capacitance.

And your mention of the  0.001 Ohm resistance rating for the cabling - what length and thickness is that with reference to? Even better if you can provide info regarding the make and model of such a low resistance cable. Even silver cabling I measured using a multimeter is about 0.2 Ohm per meter.

Resistance wise, there is this article at http://www.audioholics.com/audio-video-cables/speaker-cable-gauge (http://www.audioholics.com/audio-video-cables/speaker-cable-gauge)
Title: Re: Bi-wiring - Yea or nay
Post by: jb on October 18, 2016, 10:40:21 AM
The spice tool will only simulated whatever resistance, capacitance or inductance that you add to the circuit and sure will show on the impedance curve. For me a good speaker cable design should have minimum resistance, inductance and capacitance. And the smaller the capacitance the better as the time to charge and discharge is shorter and will give a faster speed cable.

I have measured a 2m Nordost Heimdall spk cable and give a 1 milli-Ohm reading. I think you 0.2 Ohm reading is too high for speaker cable , if for a bass burst of 10 ms , your circuit draw up to 80A current, your voltage drop across the 0.2 Ohm is 16V... that is too much signal loss at that....  thus most spk cable will use multi gauge to reduce the resistance to below 10 milli-ohm or as low as possible.

If you read on the web link that you attached, a 12 AWG zip cord has about 3.4 m Ohm per foot, so if you use multi gauge cord the resistance should be below 10 m ohm for 2m cable for a well design spk cable.

http://www.audioholics.com/audio-video-cables/speaker-cable-length-differences-do-they-matter
Title: Re: Bi-wiring - Yea or nay
Post by: WCK on October 18, 2016, 01:29:40 PM
What multimeter do you use? Most digital multimeters are up to 2-decimal points only.

Or was the 0.0001 reading when the selector was at the kOhm setting? If so it is 0.1 Ohm - see http://www.convertunits.com/from/ohm/to/kiloohm as when you enter 0.1 Ohm it is converted to 0.0001 kOhm
Title: Re: Bi-wiring - Yea or nay
Post by: Wizardofoz on October 18, 2016, 02:00:26 PM
You need to measure with something like an LCR bridge that is more a test lab type of equipment.

I use a Fluke pm6303

(http://www.kandelelectronics.com/images/products/8405.jpg)
Title: Re: Bi-wiring - Yea or nay
Post by: jb on October 18, 2016, 02:17:25 PM
I am using a fluke multimeter, of course if you have access to agilent range of multimeter that will give you more accurate test result.
Title: Re: Bi-wiring - Yea or nay
Post by: jb on October 18, 2016, 02:31:36 PM
I think Wizardofoz has a more accurate impedance analyzer than what I have, may be bring u cable at his place and have a measurement and see what resistance it give? may be we all can bring our different brand of speaker cable and test out at his place and list the test results of all those brand spk cable... that will be interesting...to see what kind of impedance it measured...

As the fluke PM6303 allow measurement of resistance, inductance and capacitance, and if we only do measurement of less than 100 KHz frequency it will give quite accurate results.
Title: Re: Bi-wiring - Yea or nay
Post by: jb on October 18, 2016, 02:54:01 PM
attached below is common copper AWG gauge and measured resistance FYI... so a 1mm copper wire will have 0.021 Ohm per meter...

(http://i.imgur.com/6M3oXJD.jpg)

source: http://www.daycounter.com/Calculators/AWG.phtml
Title: Re: Bi-wiring - Yea or nay
Post by: Wizardofoz on October 18, 2016, 02:56:03 PM
My fluke is old and probably out of calibration by now and I also have an Agilent multimeter too that does a reasonable job of of LCR too. Not sure how to set the frequency range as I think it's maybe fixed at 1KHz

I did at one time do some speaker cable tests on a test cable set that watchdog did some years ago.

While listening tests are so subjective, test equipment doesn't always tell the whole story either as components will often interact differently when combined
Title: Re: Bi-wiring - Yea or nay
Post by: jb on October 18, 2016, 03:20:09 PM
I agree speaker cable design is half science and half art, what is measured as good engineering results may not sound good...even for power amplifier does low distortion really matter? I have heard some amp spec at 0.3% distortion that sound better than those spec at 0.001% distortion...
or change a power cord and it affects the total system sound, this kind of effect cannot totally explain by engineering fact...
Title: Re: Bi-wiring - Yea or nay
Post by: Francis Huang on October 18, 2016, 10:24:52 PM
Sometimes too much a bandwidth will show more things, both gd and bad
Sometimes certain 'roll offs' is just what the sym need to sound the way we want it too

I agree speaker cable design is half science and half art, what is measured as good engineering results may not sound good...even for power amplifier does low distortion really matter? I have heard some amp spec at 0.3% distortion that sound better than those spec at 0.001% distortion...
or change a power cord and it affects the total system sound, this kind of effect cannot totally explain by engineering fact...
Title: Re: Bi-wiring - Yea or nay
Post by: jb on November 18, 2016, 09:23:43 PM
Found a LCR meter at reasonable price at Aliexpress of US$294.37, able to measure resistance down to 0.0001 ohm to 99 Mohm, C= 0.01pF to 99999uF,and L=0.01uH to 99.99KH.... value for money just don't know the product quality...But if u want to DIY speaker cable, interconnect cable or crossover circuit coil design, this will be a good tool to have. The normal multimeter resistor reading only limit to 0.1 or 0.01 OHM for most low price model , but this model can read down to 0.0001 ohm!

https://www.aliexpress.com/store/product/Tonghui-TH2811D-LCR-Meter-Bench-0-2-10Khz-Lab-Digital-electrical-bridge-inductance-New/1800579_32366821078.html
Title: Re: Bi-wiring - Yea or nay
Post by: jb on December 14, 2016, 12:46:04 AM
yes, the two set of speaker terminals are connected to the same amplifier output in parallel. For most well design speaker cable the resistance is below 0.001 Ohm so is a small fraction of the actual speaker impedance of 4 or 8 Ohm. Thus I believe the benefit of bi wiring is from the extra inductance or capacitance of the second set of speaker cable that improve the sound and also isolated path of current driving woofer and tweeter circuit.

Since you have the SPICE tool, curious to know if it show the above? Only know of NAIM gear which have their own NACA requirement to induce capacitance.

And your mention of the  0.001 Ohm resistance rating for the cabling - what length and thickness is that with reference to? Even better if you can provide info regarding the make and model of such a low resistance cable. Even silver cabling I measured using a multimeter is about 0.2 Ohm per meter.

Resistance wise, there is this article at http://www.audioholics.com/audio-video-cables/speaker-cable-gauge (http://www.audioholics.com/audio-video-cables/speaker-cable-gauge)

Hi WCK, I can measure your silver cable for you if u want to? you measured at 0.2 Ohm is because you multimeter resolution is at 0.1 Ohm , so will not be able to measure anything below 0.1 Ohm. And if you have speaker cross over also can be measure to look at the frequency response.
Title: Re: Bi-wiring - Yea or nay
Post by: Marin0 on December 16, 2016, 11:59:41 AM
Hi all,

This is my first post reply ;D
I quote reply from my friends who are professional in this area -

When it comes to speaker wires , they do make a difference to the sound. Wires have resistance that should be minimized but also they have inductive and capacity component which do not have great effect with smaller lengths. Cable should not be rolled (inductive component) or too close in parallel (capacity component).

 Another advise -
Bi-wire and single wire give us different effect. Bi give you maybe more stage feel and single maybe more musical.

I just upgraded from single wire to bi-wire and very pleased with the sound.  8)

cheers



 
Title: Re: Bi-wiring - Yea or nay
Post by: jb on December 16, 2016, 12:23:17 PM
Welcome Marin0, yes speaker cable do make a difference in the hifi system sound. Also as you go higher up the tier of branded speaker cable, they will reduce the cable resistance to below 0.00X ohm with some XX inductance. So far I can only measure the cable resistance and inductance but not the capacitance as that will need an equipment like an audio network analyzer, with some curve fitting software to get an accurate RLC model of the cable.

 http://www.testequipmentdepot.com/usedequipment/hewlettpackard/networkanalyzers/3577a.htm

great that you enjoy your bi-wire speaker experience and looking forward for u to continue  share what you learn and experience on hifi...