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Bi-wiring La Scala's


hermann
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Anybody having experience with biwiring - not bi-amping - La Scala's?

Is there any positive effect that is worth the effort?

Can I blow the midrange/tweeter if I feed them bass frequencies directly?

I'm using a 2x2W SET amp.

Thank you for any efforts,

hermann

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Some versions of the LaScala are set up for bi-wiring. My LaScala crossosver has two red wires from the input terminal to the bass section. I have been told that all I need do is cut the two red wires and run one set to the normal input terminals and the other set to the woofer terminals.

Bi-wiring does not change any crossover functions, it just feeds the bass and treble down different wires rather than the same wire. Some feel it makes a difference.

I have not tried it so maybe soneone else can give you feedback on the "benefits".

Personally I would be more worried about feeding the speakers with under powered amps (yes, yes I know it is a sacred subject). My reason for saying this is that underpowered amps have a greater tendency to damage tweeters by clipping if you get them too loud. The resulting high frequencies then sent to the tweeter are out of proportion to the highs present in a musical signal.

I would believe that bi-amping would offer more benefits but is more difficult and more expensive by far.

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I have to agree with John. You can modify your crossover to biwire your La Scalas and I can tell you how, if you tell me which crossover you have. Yes, you can damage the squawker and tweeter if you send bass frequencies to them. However, you seem to be a candidate for true biamping. Another power amp for the bass horn, perhaps larger, and an electronic crossover and you'll be set.

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  • 4 weeks later...

I JUST GOT A PAIR OF LA SCALAS AND I USE THEM ON MY BI-AMP

DJ SYSTEM.I DRIVE THE LOWS WITH A CS-1000X PEAVEY POWER AMP AND THE HIGHS WITH A CS-200 PEAVEY POWER AMP.THE LA SCALAS SOUNDS GREAT.I DON'T HAVE TO PUT ALOT OF POWER IN THEM AT ALL.MATTER OF FACT I JUST USE THE LA SCALAS FOR LARGE VENUES.

THE LA SCALA SOUNDS GOOD FULL RANGE.BUT TRY BI-AMPING THEM,YOU WOULD BE AMAZED.

TWO PEAVEY SP 2G

TWO KLIPSCH LA SCALAS,SOON 4 LA SCALAS

ONE CS 1000X PEAVEY POWER AMP

ONE CS 200X PEAVEY POWER AMP

TWO PL 500 X-OVERS

ONE PEAVEY Q-215 EQUALIZER

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Hi! Matt

Welcome to the forum.

A point of forum etiquette. The use of all caps indicates shouting. In addition this forum recently had the unfortunate experience of having a member who was an obnoxious troublemaker who used all caps in every post so members here are likely to be especially sensitive to that issue.

Congratulations on having Lascala's for quality public address purposes as that is what they were originally designed for. Unlike most other PA speakers they are equally at home on the stage or in the house.

Damned good choice.

You might wish to reconsider the amplification however- You have way more power there than is either safe for your speakers or necessary to fill a large venue with sound.

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Thanks lynnm for the heads up on the caps.

Do you really think it's to much power?

The cs-1000 is 500 watts per channel into 4 ohms.

THE peavey sp-2g's woofer is rated at 400 watts cont.

whaich takes most of the power and the la scala is rated

100 cont.which i can't belive.

I've done block parties with one la scala and had no issues.

But if you say it's too much,I'll watch it.

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Thanks lynnm for the heads up on the caps.

Do you really think it's to much power?

The cs-1000 is 500 watts per channel into 4 ohms.

THE peavey sp-2g's woofer is rated at 400 watts cont.

whaich takes most of the power and the la scala is rated

100 cont.which i can't belive.

I've done block parties with one la scala and had no issues.

But if you say it's too much,I'll watch it.

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I have a question on this bi-wiring business.

I have LaScalas with the crossovers with the red wires. I would like to clarify exactly how to connect the bi-wiring.

If I disconnect the 2 red wires what happens?

Where do I feed the full freq. range signal to the crossovers for the mids/highs? I was under the impression you just leave the same speaker wires hooked up to the usual inputs.

Then run a second set from the additional amp to the bass crossover input (red wires??), not the woofer input itself.

This way you are feeding full freq. range for all drivers and the crossover is still doing its job, but the bass is fed from a second amp into just the bass portion of the crossover.

Is this correct or wrong?

Anyhow, exactly what connections get made to bi-wire the LaScalas?

I appreciate the answers to this. I just obtained an extra amp that I am considering using in this application to get more bass out of the Las.

Thanks

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  • 1 month later...

Mark1101,

You stated:

This way you are feeding full freq. range for all drivers and the crossover is still doing its job, but the bass is fed from a second amp into just the bass portion of the crossover.

Is this correct or wrong?

You are partially right. The red wires carry the full signal from the normal input terminals to the bass section, so removing them isolates the woofer from it's input and the mid/highs are none the wiser. A second set of wires (from the same and only) amplifier is used to send the full range to the woofer like the red wires did. The only difference is that the bass and mid/high get to the speaker via two wire pairs rather than one. I have not done that so cannot say what kind of difference it makes in the resulting sound.

However you mentioned the use of a second amplifier. That becomes bi-amping and not bi-wiring. It is a different beast altogether. Bi-amp gives one the ability to run both amps full range and continue to let the speaker xover do it's thing. But the better plan would be to limit each amp to it's separate range (a low and a mid/high) amp. This improves the damping to the woofer and helps the amps as well since the power is shared and not duplicated. The mid/high amp would still need the speaker's mid/high xover in order to protect the drivers, which cannot tolerate much power outside their intended ranges.

It is fairly straight forware but not trivial persuit.

Hope this helps out. Good luck

Perhaps others can comment on the resulting sound from bi-amp setups.

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  • 18 years later...

18 years later, haha

 

Anyway, I respect both camps because it is just a hobby and the decision is not about rescuing Apollo 13 or not.

My opinion and experience is against bi-wiring because I miss the feel of good timing and impulse like I have it with a single wire. The win of „pseudo“ 3D in some cases is not my cup of tea.

Have a look here also:

http://www.achievum.eu/bi-wiring.html

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In the past I have tried bi-wiring many different speakers & wire combos. And IMHO unless you are using a wire gauge that is too small for your wire load/run it made no difference what so ever. Now if you were to bi-amp we are talking about another thing all together.

 

 

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Using two amplifiers into a divided passive crossover, with the bass portion separate from the mid and tweeter section, has obvious audible benefits.  When I do this, I use an RCA splitter on my source so that I can plug into two separate power amps. One amp powers the bass portion, and the other amp powers the mid and treble portion in a three way, or the single HF driver in a two way.  At least one, but ideally both amplifiers should have a volume control.  Using two amplifiers instead of one confers multiple benefits. This makes it possible, for example, to use a 45 amp on the highs, and a push-pull EL34 amp on the lows.  Obviously, it depends on the existing crossover as the crossover needs to be split, but that should be doable in many cases using the parts in the existing crossover.  For most of the Klipsch crossovers I’ve seen, it’s pretty easy.  

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I see no advantage to bi-wire unless you have a very long speaker cable run. Then, in this case you can run an very large gauge wire for the woofer for good damping, this wire will now have enough inductance to possibly effect the high frequency response so you run a smaller gauge high strand count wire for the mids and tweeter that doesn't require the amount of damping the woofer does. Other than that I see zero advantage to bi-wire.

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That today almost every ordinary and many of the more expensive speakers provide a division of the bass and treble connections is good for the perhaps 2% of customers who bi-amp. For the 98% who don't it has rather disadvantages. For manufacturers, it's a catch-22. 35 years ago, bi-wiring terminals were a USP for a few manufacturers. Today many consumers without technical knowledge look during the purchase decision whether the "option bi-wiring" is there or not...Simply: "Is it there"...but not "does it make sense for me".

 

For some consumers, disadvantage 1 is that manufacturers and Hifi magazine tempt them to spend money on expensive superfluous cables. For many unsuspecting consumers, it must seem like a "norm" or a "standard", with the constant call to supposedly "upgrade". Most manufacturers naturally want to offer this option to customers who want to bi-amp, which is understandable in the competitive market. The final winner is the cable industry.

 

Disadvantage 2 is a technical one so that the split ports do not sound as good as a single port for the whole freq. region because of the additional contact zones when you connect only one cable. 
Here's a tip. When long thin connecting rods between bass and tweeter input are given it has helped me if I tighten the threaded connections very! very! carefully with a pair of combination pliers. Between the pliers and the threaded connection (where you put the bananas in) I take a thin kitchen towel to not scratch anything.

The goal is to turn only a little tighter than your fingers can do, but not to break anything. As a result, the treble sounds noticeably silkier when I plug the cable into the bass. The reason will be that the connectors vibrate less and there is less micro-interruption of the contacts.

For connectors that use flat plates between bass and tweeter input I would suggest the same principle. But here I would recommend even more to try a short piece of speaker cable, bare without solder at the ends, instead of the flat thin sheet and tighten it in the same way.

I have had better results when the cable is in the bass clamps. Some companies, like Tannoy, recommend plugging the single run cable into the tweeter. Here I would just try what is better in your case and to your ears.

 

The completely crazy thing is that many people prefer the sound of bi-wiring only! because for the first time the four contacts are right due to the cable plugs.

The most stupid (or the most clever) thing is that now short pieces of cables are offered that make a divider before the speaker terminals for people without bi-wiring, two inputs and four outputs. This gives you four additional superfluous and quality-reducing contact points.
Such very short distribution cables can cost hundreds of dollars each. So the cable industry also benefits from some consumers with a single run of cable.

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On 1/8/2022 at 8:04 AM, KT88 said:

That today almost every ordinary and many of the more expensive speakers provide a division of the bass and treble connections is good for the perhaps 2% of customers who bi-amp. For the 98% who don't it has rather disadvantages. For manufacturers, it's a catch-22. 35 years ago, bi-wiring terminals were a USP for a few manufacturers. Today many consumers without technical knowledge look during the purchase decision whether the "option bi-wiring" is there or not...Simply: "Is it there"...but not "does it make sense for me".

 

For some consumers, disadvantage 1 is that manufacturers and Hifi magazine tempt them to spend money on expensive superfluous cables. For many unsuspecting consumers, it must seem like a "norm" or a "standard", with the constant call to supposedly "upgrade". Most manufacturers naturally want to offer this option to customers who want to bi-amp, which is understandable in the competitive market. The final winner is the cable industry.

 

Disadvantage 2 is a technical one so that the split ports do not sound as good as a single port for the whole freq. region because of the additional contact zones when you connect only one cable. 
Here's a tip. When long thin connecting rods between bass and tweeter input are given it has helped me if I tighten the threaded connections very! very! carefully with a pair of combination pliers. Between the pliers and the threaded connection (where you put the bananas in) I take a thin kitchen towel to not scratch anything.

The goal is to turn only a little tighter than your fingers can do, but not to break anything. As a result, the treble sounds noticeably silkier when I plug the cable into the bass. The reason will be that the connectors vibrate less and there is less micro-interruption of the contacts.

For connectors that use flat plates between bass and tweeter input I would suggest the same principle. But here I would recommend even more to try a short piece of speaker cable, bare without solder at the ends, instead of the flat thin sheet and tighten it in the same way.

I have had better results when the cable is in the bass clamps. Some companies, like Tannoy, recommend plugging the single run cable into the tweeter. Here I would just try what is better in your case and to your ears.

 

The completely crazy thing is that many people prefer the sound of bi-wiring only! because for the first time the four contacts are right due to the cable plugs.

The most stupid (or the most clever) thing is that now short pieces of cables are offered that make a divider before the speaker terminals for people without bi-wiring, two inputs and four outputs. This gives you four additional superfluous and quality-reducing contact points.
Such very short distribution cables can cost hundreds of dollars each. So the cable industry also benefits from some consumers with a single run of cable.

It seems likely that much of the perceived benefit of bi-wiring is, as you say, due to a better connection being made by the home user when they bi-wire.  Perhaps I am missing something, but I can’t see how it would make a difference to attach two sets of wires to your amplifier’s output rather than splitting the power at the speaker.  What’s the difference? That said, splitting a crossover into parts and powering each part with a separate amp does make a difference.  The source is split so that two stereo amplifiers get the same signal.  In the case of a two way, one amplifier is connected to the LF section, and the other amplifier is connected to the HF section.  The amplifier responsible for the HF feeds a driver with far lower power requirements. This amplifier is not called upon to power the LF portion of the signal, and therefore HF reproduction is not affected by the work required to power the LF as when one amp feeds both LF and HF.  The HF amp has an easier job, and avoids the modulation of its output by the needs of the LF section.  This is based upon my online research a few years back.  Basically, I was trying to figure out if a tube amp output transformer would be impacted by receiving the full signal from the source, and amplifying that signal into a passive high pass filter that kept the LF frequencies from reaching the driver.  This was in order to build an HF tube amp with smaller, less expensive output transformers that also, in my experience, produce better quality HF response than that from large OPTs.  The answer I got at the time was that if an amp powers an HF crossover, the LF portion of the signal that doesn’t draw power also doesnt affect the amps performance any more.  It’s effectively not there.  This may be entirely incorrect, but it’s what I got out of my questions at the time.

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4 hours ago, Tizman said:

It seems likely that much of the perceived benefit of bi-wiring is, as you say, due to a better connection being made by the home user when they bi-wire.  Perhaps I am missing something, but I can’t see how it would make a difference to attach two sets of wires to your amplifier’s output rather than splitting the power at the speaker.  What’s the difference? That said, splitting a crossover into parts and powering each part with a separate amp does make a difference.  The source is split so that two stereo amplifiers get the same signal.  In the case of a two way, one amplifier is connected to the LF section, and the other amplifier is connected to the LF section.  The amplifier responsible for the HF feeds a driver with far lower power requirements. This amplifier is not called upon to power the LF portion of the signal, and therefore HF reproduction is not affected by the work required to power the LF as when one amp feeds both LF and HF.  The HF amp has an easier job, and avoids the modulation of its output by the needs of the LF section.  This is based upon my online research a few years back.  Basically, I was trying to figure out if a tube amp output transformer would be impacted by receiving the full signal from the source, and amplifying that signal into a passive high pass filter that kept the LF frequencies from reaching the driver.  This was in order to build an HF tube amp with smaller, less expensive output transformers that also, in my experience, produce better quality HF response than that from large OPTs.  The answer I got at the time was that if an amp

powers an HF crossover, the LF portion of the signal that doesn’t draw power also doesnt affect the amps performance any more.  It’s effectively not there.  iThis may be entirely incorrect, but it’s what I got out of my questions at the time.

To the best of my knowledge, I would put it this way: With passive bi-ampimg, i.e. when both amps get the full signal from the pre amp, I would not be sure if the tube amp that sits in front of the HF part of the xover would not suffer. If about 90% of the energy is absorbed by the LF section then the output transformer before the HF section of the xover would run largely without a load connected. This could lead to sparking in the OT.

It is a different story with an active xover, i.e. when the crossover sits in front of the amps. In this case, the tube amp for the HF part is supplied exclusively with the HF signal. The OT gets only the part that is called from the voice coil of the tweeter and no load that runs "into the void". This way I used a tube amp for many years and it was without any problems.
I would like to ask others who understand more about this to post whether my warning about passive bi-amping a HF section with tube amps is correct or not.

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On 1/13/2022 at 2:22 AM, KT88 said:

To the best of my knowledge, I would put it this way: With passive bi-ampimg, i.e. when both amps get the full signal from the pre amp, I would not be sure if the tube amp that sits in front of the HF part of the xover would not suffer. If about 90% of the energy is absorbed by the LF section then the output transformer before the HF section of the xover would run largely without a load connected. This could lead to sparking in the OT.

It is a different story with an active xover, i.e. when the crossover sits in front of the amps. In this case, the tube amp for the HF part is supplied exclusively with the HF signal. The OT gets only the part that is called from the voice coil of the tweeter and no load that runs "into the void". This way I used a tube amp for many years and it was without any problems.
I would like to ask others who understand more about this to post whether my warning about passive bi-amping a HF section with tube amps is correct or not.


The explanation I got was that because the crossover doesn’t pass the LF portion to the speaker, the current draw that would otherwise happen isn’t there anymore. In other words, the driver is the load, and if the driver isn’t drawing current for the LF that is filtered out by the crossover, the amp doesn’t need to supply the power to the missing LF portion.  Again, this information is based on my questions about using small output transformers on an amp built for just the HF section of a horn two way.  
 

I currently own three electronic crossovers.  I would love to use them, but I have found that every one adds too much noise for my very quiet listening room, and that passives just sound better.  I wish it wasn’t so, because using an active crossover would simplify things greatly, but it is.  

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