Speakers are FAR away from amp, any recommendations? - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #1 of 39 Old 07-25-2009, 06:55 AM - Thread Starter
Member
 
destropaul's Avatar
 
Join Date: Nov 2008
Location: Southern California
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Off the multi-zone of a Pioneer Elite receiver, powered by the Elite M10X amplifier (4ohms/100Watts/2ch), we have two-pair, eight-ohm outdoor speakers ran in parallel.
Two speakers are about 400' away from the amplifier, the other two are about 150' away. The closer of the pair is ran through an impedance volume control. All wired with 14-gauge speaker-wire.
Rewiring is not a possibility, my multi-meter reads about 3ohms back to the amplifier, any suggestions how to improve this setup without spending a great deal of $$? Should I have an impedance strip? Impedance Volume knob for the long pair?
- Paul
destropaul is offline  
Sponsored Links
Advertisement
 
post #2 of 39 Old 07-25-2009, 04:11 PM
AVS Special Member
 
tvrgeek's Avatar
 
Join Date: Feb 2009
Location: Bowie, MD.
Posts: 2,146
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 25
Adding volume controls (L-pads) is exactly the wrong direction. About the only thing to do is drive each pair with it's own amp and own preamp level volume control. What you are loosing is just a touch of the lowest bass. If it is background music, you have no problem anyway.

You did not say if you had any sonic problem. Don't worry about "improving" a problem that may not exist.
tvrgeek is offline  
post #3 of 39 Old 07-26-2009, 04:38 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,279
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 674 Post(s)
Liked: 1142
Quote:
Originally Posted by destropaul View Post

Off the multi-zone of a Pioneer Elite receiver, powered by the Elite M10X amplifier (4ohms/100Watts/2ch), we have two-pair, eight-ohm outdoor speakers ran in parallel.
Two speakers are about 400' away from the amplifier, the other two are about 150' away. The closer of the pair is ran through an impedance volume control. All wired with 14-gauge speaker-wire.

If you want top fidelity, you screwed up when you laid that too-thin wire.

This is a problem that is most economically and easily addressed by upgrading the wire to one with heavier gauge.

You lept before you thought. You didn't do your homework. You went cheap when the proper solution would not be that costly to implement, provided it was done up front. You have created a problem that will be costly to address, no matter how you address it.

Quote:


Rewiring is not a possibility,

It's the best answer.

Quote:


my multi-meter reads about 3ohms back to the amplifier,

14 gauge wire has .00297 ohms per foot. A 400 foot pair has 800 feet of wire in it. The actual expected resistance would be 2.376 ohms. This is way too much. You'd like the resistance of a speaker cable to be between 10 and 100 times less than the lowest impedance at any audio frequency of the speaker load. If you have 4 ohm speakers, you might want to have the cable resistance no more than 0.4 ohms, and preferably much less than that.

You really need something like number 8 or better wire for this application.

The resistance of copper wire is well-known. Why didn't you think about this before you laid the wire? Do you think that 400' runs of speaker cable are every-day occasions and you can just do what feels good and is cheap?

Quote:


any suggestions how to improve this setup without spending a great deal of $$?

Probably not.

My first thought is repurpose the existing wire as a 120 volt power line and move the electronics out to the speakers. Or, if there is 120 volt power out there, put another amplifier or receiver out there and repurpose the existing wires as signal links using audio baluns.

http://www.tristateu.com/itemdesc.asp?ic=MAE-P115-01Q

My second thought would be to use a professional-engineered approach called a "70 volt" system, which involves putting speaker-level audio transformers at the beginning and end of the long lines. They will raise the voltage but reduce the voltage on your under-sized cables. This reduces losses due to the resitance of the wire. These transformers will have to be exceptionally high quality and therefore expensive.

4 of these could fix you up:

http://www.qscstore.com/ot300a.html

Most 70 volt systems inuse are voice grade, and reduce sound quality. You'll need something that is very heavy duty and over-built if you want good sound quality.

Quote:


Should I have an impedance strip? Impedance Volume knob for the long pair?

Neither approach will work. They are going backwards.
arnyk is offline  
post #4 of 39 Old 07-26-2009, 06:31 AM
AVS Special Member
 
tvrgeek's Avatar
 
Join Date: Feb 2009
Location: Bowie, MD.
Posts: 2,146
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 25
70 V systems are for PA use. You will get no bass and the transformers are not music quality.
Quit worrying about it and put on some music.
tvrgeek is offline  
post #5 of 39 Old 07-26-2009, 06:52 AM - Thread Starter
Member
 
destropaul's Avatar
 
Join Date: Nov 2008
Location: Southern California
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Thanks for the input. To respond to the multiple "cheap" accusations from arnyk above^.... the original plan was for two speakers, about 100' away, we used good-quality 14-gauge direct-burial wire. The customer was repeatably making changes and additions to what we have now, most changes were after the cement was laid over all the wire.
As a result, we may be forced to have only the Two original speakers wired.
- Paul
destropaul is offline  
post #6 of 39 Old 07-26-2009, 10:05 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,279
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 674 Post(s)
Liked: 1142
Quote:
Originally Posted by tvrgeek View Post

70 V systems are for PA use. You will get no bass and the transformers are not music quality.

You obviously did not follow up on the link to QSC that I supplied.

IOW, you are intentionally poorly informed on the topic at hand.
arnyk is offline  
post #7 of 39 Old 07-26-2009, 10:11 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,279
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 674 Post(s)
Liked: 1142
Quote:
Originally Posted by destropaul View Post

Thanks for the input. To respond to the multiple "cheap" accusations from arnyk above^.... the original plan was for two speakers, about 100' away, we used good-quality 14-gauge direct-burial wire. The customer was repeatably making changes and additions to what we have now, most changes were after the cement was laid over all the wire.
As a result, we may be forced to have only the Two original speakers wired.
- Paul

100' is generally too long of a run for 14 gauge wire and high quality operation unless the speakers are designed to work well with such high source impedance. Do the math - the resistance of 100' of 14 guage is about 0.65 ohms which somewhat fails the 10:1 minimum rule, and does not even come close to the 100:1 rule for most speakers. Many 8 ohm rated speakers fall to 4-6 ohms somewhere in the audio range.

However, your comment does suggest a third approach. This would be to add a parametric equalizer at the source end, and equalize the drive to the speakers so that the voltage at the remote speaker terminals is flat +/- < 1 dB over the bandpass of the speakers.

I was thinking about the costs of 8 gauge wire, and it is possible that buried 8 gauge wire would be so expensive that one of the other approaches would be more cost effective, for acceptable performance.
arnyk is offline  
post #8 of 39 Old 07-26-2009, 10:23 AM
 
ChrisWiggles's Avatar
 
Join Date: Nov 2002
Location: Seattle
Posts: 20,730
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Quote:
Originally Posted by tvrgeek View Post

Adding volume controls (L-pads) is exactly the wrong direction. About the only thing to do is drive each pair with it's own amp and own preamp level volume control. What you are loosing is just a touch of the lowest bass. If it is background music, you have no problem anyway.

You did not say if you had any sonic problem. Don't worry about "improving" a problem that may not exist.

If it sounds alright now, dont' worry about it. They're outdoor speakers. Are we really going to be picky to the nth degree here? For outdoor background/party music? See what it sounds like as-is first, and if it sounds fine (I'll bet it does), then don't worry about it.
ChrisWiggles is offline  
post #9 of 39 Old 07-26-2009, 10:41 AM
AVS Special Member
 
whoaru99's Avatar
 
Join Date: Dec 2004
Posts: 6,960
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 67
Quote:
Originally Posted by destropaul View Post

Off the multi-zone of a Pioneer Elite receiver, powered by the Elite M10X amplifier (4ohms/100Watts/2ch), we have two-pair, eight-ohm outdoor speakers ran in parallel.
Two speakers are about 400' away from the amplifier, the other two are about 150' away. The closer of the pair is ran through an impedance volume control. All wired with 14-gauge speaker-wire.
Rewiring is not a possibility, my multi-meter reads about 3ohms back to the amplifier, any suggestions how to improve this setup without spending a great deal of $$? Should I have an impedance strip? Impedance Volume knob for the long pair?
- Paul

Your question about improvement is vague.

What is it about the actual performance of the system that you (or the customer??) are wanting to improve?

Just because there is a knob doesn't mean you should turn it.
whoaru99 is offline  
post #10 of 39 Old 07-26-2009, 01:14 PM
AVS Special Member
 
tvrgeek's Avatar
 
Join Date: Feb 2009
Location: Bowie, MD.
Posts: 2,146
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 25
Quote:
Originally Posted by arnyk View Post

You obviously did not follow up on the link to QSC that I supplied.

IOW, you are intentionally poorly informed on the topic at hand.

Actually, I did. I stand by my conclusions until I have heard or seem objective measurements to suggest otherwise. Just because a part is listed is some catalog does not show that it would "improve" the situation the OP is concerned with.

I stand by my conclusion. My opinion without needless snide comments.
tvrgeek is offline  
post #11 of 39 Old 07-26-2009, 02:40 PM - Thread Starter
Member
 
destropaul's Avatar
 
Join Date: Nov 2008
Location: Southern California
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Here I will elaborate on the problem(s) I've encountered...
- Either pair of the two pairs of speakers (volume control or not) sound perfectly good when driven by the second zone speaker terminals off the main theater receiver.
- When I connect the multi-zone, pre-amp output of the receiver to the external amplifier, the farther pair of speakers emit very loud noises, when testing the closer pair, these sound fine.
- I tested the source by connecting the separate amplifier to the DVD/Cd-players output directly. Now all four speakers sound good (even when driven all at once in parallel) and there doesn't seem to be any problems. ??

- I tried putting a line-level attenuator between the multi-zone pre-output and the amp, the loud noise slowly ramped as I adjusted the attenuator.
- I tried a volume knob for the further speakers and this did no good.

Could the receivers analog board be screwed up? Why would music sound fine from this pre-amp multi-zone output when using the closer of the speakers but not the far?
destropaul is offline  
post #12 of 39 Old 07-26-2009, 04:01 PM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,279
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 674 Post(s)
Liked: 1142
Quote:
Originally Posted by tvrgeek View Post

Actually, I did. I stand by my conclusions until I have heard or seem (sic) objective measurements to suggest otherwise. Just because a part is listed is some catalog does not show that it would "improve" the situation the OP is concerned with.

I stand by my conclusion. My opinion without needless snide comments.

You made your own snide comment. You've got zero evidence to support your claim that the high quality transformers in question will cause the same problems as the cheap products you seem to be basing your opinions on.

Using your own words, until (you) have heard or seem(sic) objective measurements that support your claims, you have nothing to stand on but your own prejudice.
arnyk is offline  
post #13 of 39 Old 07-26-2009, 04:03 PM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,279
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 674 Post(s)
Liked: 1142
Quote:
Originally Posted by destropaul View Post

Here I will elaborate on the problem(s) I've encountered...
- Either pair of the two pairs of speakers (volume control or not) sound perfectly good when driven by the second zone speaker terminals off the main theater receiver.
- When I connect the multi-zone, pre-amp output of the receiver to the external amplifier, the farther pair of speakers emit very loud noises, when testing the closer pair, these sound fine.
- I tested the source by connecting the separate amplifier to the DVD/Cd-players output directly. Now all four speakers sound good (even when driven all at once in parallel) and there doesn't seem to be any problems. ??

- I tried putting a line-level attenuator between the multi-zone pre-output and the amp, the loud noise slowly ramped as I adjusted the attenuator.
- I tried a volume knob for the further speakers and this did no good.

Could the receivers analog board be screwed up? Why would music sound fine from this pre-amp multi-zone output when using the closer of the speakers but not the far?

Yes. I can't believe that you can't troubleshoot this problem more effectively.
arnyk is offline  
post #14 of 39 Old 07-26-2009, 08:02 PM - Thread Starter
Member
 
destropaul's Avatar
 
Join Date: Nov 2008
Location: Southern California
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
arnyk, so please enlighten me. This is why I am here. Thank you.
destropaul is offline  
post #15 of 39 Old 07-26-2009, 09:24 PM
AVS Special Member
 
MLKstudios's Avatar
 
Join Date: Jun 2007
Location: Hollywood, CA
Posts: 1,986
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
What about a wireless set up?
MLKstudios is offline  
post #16 of 39 Old 07-27-2009, 04:43 AM
AVS Special Member
 
whoaru99's Avatar
 
Join Date: Dec 2004
Posts: 6,960
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 67
What sort of noise are the speakers making?

Just because there is a knob doesn't mean you should turn it.
whoaru99 is offline  
post #17 of 39 Old 07-27-2009, 06:45 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,279
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 674 Post(s)
Liked: 1142
Quote:
Originally Posted by destropaul View Post

arnyk, so please enlighten me. This is why I am here. Thank you.


If I had an amp that was making funny noises driving a load 400 feet away, I'd try another amp. Seems like you eventually revealed that you did that and it helped, big time.

That means to me that amp number one has some problems. If it is in warranty get it fixed. As expensive as it seems to be, probably get it fixed anyway.
arnyk is offline  
post #18 of 39 Old 07-27-2009, 06:50 AM - Thread Starter
Member
 
destropaul's Avatar
 
Join Date: Nov 2008
Location: Southern California
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
The thing is, that same amp works just fine with the alternative pre-amp sources. We do have two of these amps in the home so today I'll swap them and see what happens.
&.... The noises it makes are a full-volume screeching wail, the only way I can describe it.
destropaul is offline  
post #19 of 39 Old 07-27-2009, 06:51 AM - Thread Starter
Member
 
destropaul's Avatar
 
Join Date: Nov 2008
Location: Southern California
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
wireless may be an alternative for the two farthest speakers, however, the closer ones would be hard-wired, they are in the same zone and I wouldn't want there to be a delay of any kind.
destropaul is offline  
post #20 of 39 Old 07-27-2009, 09:50 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,279
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 674 Post(s)
Liked: 1142
Quote:
Originally Posted by destropaul View Post

The thing is, that same amp works just fine with the alternative pre-amp sources. We do have two of these amps in the home so today I'll swap them and see what happens.
&.... The noises it makes are a full-volume screeching wail, the only way I can describe it.


A full-volume screeching wail suggest some kind of hidden feedback path from the amps output, back to its input.

Also, make sure that none of your speaker wires are grounded or connected to anything but the amplifer and the speakers.

Ensure that the ground lines to your L & R speakers are not interchanged.
arnyk is offline  
post #21 of 39 Old 07-27-2009, 01:18 PM
AVS Special Member
 
tvrgeek's Avatar
 
Join Date: Feb 2009
Location: Bowie, MD.
Posts: 2,146
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 25
Quote:
Originally Posted by arnyk View Post

You made your own snide comment. You've got zero evidence to support your claim that the high quality transformers in question will cause the same problems as the cheap products you seem to be basing your opinions on.

Using your own words, until (you) have heard or seem(sic) objective measurements that support your claims, you have nothing to stand on but your own prejudice.


Arn,
I have my experience, and as I stated, hold my conclusions until shown otherwise. If the solution you propose is high fidelity, please point me to any source that would provide specifications or testing results. I don't believe product placement pages at first pass. I would love to see a product that could overcome very long lines without the normally expected distortion and LF frequency loss associated with transformers. If you would, show that these "expensive" (not really, compared to a decent output transformer) transformers are of the quality you suggest. Many may be interested.
tvrgeek is offline  
post #22 of 39 Old 07-27-2009, 01:45 PM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,279
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 674 Post(s)
Liked: 1142
Quote:
Originally Posted by tvrgeek View Post

Arn,
I have my experience, and as I stated, hold my conclusions until shown otherwise.

Why are you making such a strong point of your ignorance about how 70 volt works with good transformers?

*Everybody* knows that the standard 70 volt transformers that are commonly used with distributed sound systems are POS.

I pointed you at a quality product from a quality source. If you've got questions about the product, ask QSC - they can be very good about customer service.
arnyk is offline  
post #23 of 39 Old 07-27-2009, 03:04 PM
AVS Special Member
 
tvrgeek's Avatar
 
Join Date: Feb 2009
Location: Bowie, MD.
Posts: 2,146
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 25
I have no need for them. It was you who are offering the proposition that they are suitable for Paul's original question. Considering no specific problem was originally stated, adding $500 worth of transformers does not sound like a reasonable low cost solution to an undefined problem. He elaborated on the symptoms, on which I will comment later.

I do not consider standard 70V transformers "POS". I consider them suitable for their indented use. PA. I suspect their manufactures would take exception to your view of them. I have found some of low quality, and some that met the intended use quite well.

On the further explanation of the OP's symptoms. It could be that the receiver in question does not like the load from the 400 feet of wire and is becoming unstable. I had a situation where long cables acted like AM antennas and the feedback circuit a detector, so the speakers played a horrible screech that could just be identified as a CB broadcast. ( I found the illegal 1000W CB radio and "fixed" the problem.)
It could be that the builder damaged the cable and moisture got in. You would need a megger and a TDR to eliminate that as a possibility.
tvrgeek is offline  
post #24 of 39 Old 07-28-2009, 10:20 AM
Member
 
jtreibick's Avatar
 
Join Date: May 2008
Posts: 52
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
From what I understand the quality of the transformers in a 70v system has a LOT to do with the resultant sound quality. I have NO personal experience with 70v installation but am looking to get into it and in my search I uncovered MANY sources stating that this is just the case. Before listening to others experiences my assumption of all 70v sound was PA or supermarket (bad) quality music. I changed my mind after I was explained/reminded that 70v is used where music quality is not always an afterthought like in churches, large venues, restaurants, etc. The installers of these systems stress that transformer quality of directly relates to the quality of sound (particularly low freq response.)

I remember reading about someone who was called out to troubleshoot a church music system and eventually replaced the junky speaker transformers with quality ones that vastly improved their bass response and overall fidelity. My electronics distributor also mentioned that in their 70v offerings they have the same speaker with different quality transformers attached (cheap for PA and quality for music.) Perhaps even high-end 70v is not able to reproduce the entire fidelity of an 8 ohm speaker, but it likely can deliver more than just PA quality. My guess is that discerning listeners could hear music on a good 70v system and be impressed with the quality (considering what it is.)

It seems like a quality 70v system may be a very reasonable solution for the thread's author if he's stuck with tiny wire gauge... even if it isn't sonically perfect or cheap.
jtreibick is offline  
post #25 of 39 Old 07-28-2009, 10:49 AM
AVS Special Member
 
whoaru99's Avatar
 
Join Date: Dec 2004
Posts: 6,960
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 67
Quote:
Originally Posted by destropaul View Post

The thing is, that same amp works just fine with the alternative pre-amp sources. We do have two of these amps in the home so today I'll swap them and see what happens.
&.... The noises it makes are a full-volume screeching wail, the only way I can describe it.

From far away, this seems to indicate it's not a problem with the amp or the long wires, but moreso something in the interaction of the preamp Z2 configuration, or Z2 output interaction with the amp input.

Are you using the exact same pair of interconnect cables in both connection experiments (Z2 output vs alternate preamp source)?

Just because there is a knob doesn't mean you should turn it.
whoaru99 is offline  
post #26 of 39 Old 07-28-2009, 11:49 AM - Thread Starter
Member
 
destropaul's Avatar
 
Join Date: Nov 2008
Location: Southern California
Posts: 23
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I have tried using the same interconnects with different pre-amp outputs. The other pre-output sources sound just fine. I have removed the receiver and brought in for repair on this issue. I'll update here once I get everything squared off. Thanks everyone for your help!
destropaul is offline  
post #27 of 39 Old 07-30-2009, 08:54 PM
Advanced Member
 
Herc's Avatar
 
Join Date: Apr 2004
Posts: 677
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 10
Quote:
Originally Posted by arnyk View Post

If you want top fidelity, you screwed up when you laid that too-thin wire.


I get that there could be issues with unsheilded long runs but I don't get the correlation between thin wire and fidelity.
Herc is offline  
post #28 of 39 Old 07-30-2009, 11:54 PM
Advanced Member
 
Ugly1's Avatar
 
Join Date: May 2007
Posts: 872
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by destropaul View Post

The noises it makes are a full-volume screeching wail, the only way I can describe it.

Sure sounds like the amp is going unstable trying to drive those long cables. You won't like the answer about how to take care of that if that is what it is. Inserting series resistance right at the amp output. yep.

To verify use an oscilloscope and look for clipped oscillation coming out of the amp. It'll look like a square wave swinging between about plus and minus 60V.
Ugly1 is offline  
post #29 of 39 Old 07-31-2009, 05:10 AM
AVS Special Member
 
whoaru99's Avatar
 
Join Date: Dec 2004
Posts: 6,960
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 67
Quote:
Originally Posted by Ugly1 View Post

Sure sounds like the amp is going unstable trying to drive those long cables. You won't like the answer about how to take care of that if that is what it is. Inserting series resistance right at the amp output. yep.

To verify use an oscilloscope and look for clipped oscillation coming out of the amp. It'll look like a square wave swinging between about plus and minus 60V.

I don't dispute is sounds something like that is going on, but....

Why, then, does the same amp seem to work just fine driving that same setup by merely changing the input signal from the receiver's Z2 outputs to a different source?

Just because there is a knob doesn't mean you should turn it.
whoaru99 is offline  
post #30 of 39 Old 07-31-2009, 05:15 AM
AVS Special Member
 
whoaru99's Avatar
 
Join Date: Dec 2004
Posts: 6,960
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 67
Quote:
Originally Posted by Herc View Post

I get that there could be issues with unsheilded long runs but I don't get the correlation between thin wire and fidelity.

Check out the Roger Russell speaker wire page for an explanation why.

Just because there is a knob doesn't mean you should turn it.
whoaru99 is offline  
Reply Audio theory, Setup and Chat

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off