Issue with Mains

Hello,

I have an older venue with two speakers hung at the proscenium arch. I have a input box on the floor backstage by the speaker lines that is connected via snake to the booth at the back of the auditorium and up to the sound booth which is on the floor above. We've recently purchased a new Pyle digital amplifier and a Behringer x32 for the space and both have worked beautifully for the last year ...until last week.
Last week we set up for a dress rehearsal of a livestream and all was working well. When we came back the next day and turned everything on we only were able to get a faint, distorted sound out of both main speakers (we set up auxiliary speakers so actors could hear for the event and still were able to mix and record via phones connected to the board). I have since reset all board presets and replaced the line going from the box backstage to the speaker line and we still cannot get anything but a weak, distorted sound to come out through the mains. I have to requisition a man lift to get up into the grid to check the lines from the speakers, but was wondering if there were any suggestions of other things I can try before doing so? I'm probably missing something fairly obvious.
Thanks!
 
Hi Dave,
Thanks for the quick response. The amp is a Pyle PTA 1000, I'm getting consistent signal readings from it and from the board. The speakers, I have no idea what model they are, but they have little "EV" insignia on the bottom. I don't have a crossover or processor currently installed.
I will reach out to my music colleagues and see if we can find another amp to do some testing with. Thanks!
 

jkowtko

Well-Known Member
This is a long shot -- but check all the speaker wiring end to end to make sure nobody is playing a practical joke on you ... back in college a buddy put a resistor and diode on the speaker wires in my stereo system and it sounded weak and garbled as you have described ... freaked me out for a bit until I figured out what was going on!
 

RonHebbard

Well-Known Member
Premium Member
Hi Dave,
Thanks for the quick response. The amp is a Pyle PTA 1000, I'm getting consistent signal readings from it and from the board. The speakers, I have no idea what model they are, but they have little "EV" insignia on the bottom. I don't have a crossover or processor currently installed.
I will reach out to my music colleagues and see if we can find another amp to do some testing with. Thanks!
Is it safe to assume your speakers are 'old fangled' passive speakers rather than 'new fangled' active speakers with built in electronics?
Is it also safe to assume your speakers are low impedance ~4 < 16 ohms rather than 70 volt paging speakers??
Toodleoo!
Ron Hebbard
 
Is it safe to assume your speakers are 'old fangled' passive speakers rather than 'new fangled' active speakers with built in electronics?
Is it also safe to assume your speakers are low impedance ~4 < 16 ohms rather than 70 volt paging speakers??
Toodleoo!
Ron Hebbard



Yes! Old fangled for sure. The building was built circa 1984 and I believe they are original to that build (I've only been here for five years and this is the first time we've had issues). But, I am fairly certain they are passive. I've rerouted with some less-powerful but definitely okay to get by active speakers for now, but would like to get our system back up and running, if possible.
 

RonHebbard

Well-Known Member
Premium Member
This is a long shot -- but check all the speaker wiring end to end to make sure nobody is playing a practical joke on you ... back in college a buddy put a resistor and diode on the speaker wires in my stereo system and it sounded weak and garbled as you have described ... freaked me out for a bit until I figured out what was going on!
Akin to when the janitor brings in one or two of his car stereo speakers, installs it/them in his broom closet, then 'hot wires' their 4 ohm voice coils to your 70 volt lines.
Toodleoo!
Ron Hebbard
 

MNicolai

Well-Known Member
Premium Member
Fight Leukemia
Seconding what @DaveySimps is saying. I would start with troubleshooting the amp before anything else. Hammering a little harder on what he said, Pyle has no reputation whatsoever for making quality commercial-grade audio equipment. Even if the speakers are blown up, I would look closely at whether the Pyle amp was somehow responsible for that.

I would try driving a different speaker on that amplifier or another amplifier on those speakers. I would also double check your cabling to make sure the signal cable from your console out to your amp does not have any shorts between pins. Use the continuity tester of a multimeter to confirm pin 1 on each of the cable is wired correctly and that there is no continuity between pin 1 and pins 2 and 3. Then wash, rinse, repeat with the other pins.

Also -- how are you powering the system on and off? Do you ever hear a "pop" or a "thump" through the speakers when you turn the system on or off? Generally you should turn the input sources and the mixer on first, amplifiers second, and power down the system by turning amplifiers off first, mixer second, in reverse order. Chances are the mixer won't cause a major problem but if you have a low-quality amplifier that's probably mismatched with your speakers' power ratings, a "thump" could overdrive the amplifier's output signal to distort enough that it sends effectively a square wave signal out your speakers which behaves like applying a DC power source directly across the crossovers and drivers which can be destructive.
 
Seconding what @DaveySimps is saying. I would start with troubleshooting the amp before anything else. Hammering a little harder on what he said, Pyle has no reputation whatsoever for making quality commercial-grade audio equipment. Even if the speakers are blown up, I would look closely at whether the Pyle amp was somehow responsible for that.

I would try driving a different speaker on that amplifier or another amplifier on those speakers. I would also double check your cabling to make sure the signal cable from your console out to your amp does not have any shorts between pins. Use the continuity tester of a multimeter to confirm pin 1 on each of the cable is wired correctly and that there is no continuity between pin 1 and pins 2 and 3. Then wash, rinse, repeat with the other pins.

Also -- how are you powering the system on and off? Do you ever hear a "pop" or a "thump" through the speakers when you turn the system on or off? Generally you should turn the input sources and the mixer on first, amplifiers second, and power down the system by turning amplifiers off first, mixer second, in reverse order. Chances are the mixer won't cause a major problem but if you have a low-quality amplifier that's probably mismatched with your speakers' power ratings, a "thump" could overdrive the amplifier's output signal to distort enough that it sends effectively a square wave signal out your speakers which behaves like applying a DC power source directly across the crossovers and drivers which can be destructive.


Awesome, thanks for this.
We don't get a thump at all, we've been pretty consistent with proper power on and off protocols. General consensus says amplifier, I've got a small mixer and other speakers we will start doing some testing with this week!
 

MNicolai

Well-Known Member
Premium Member
Fight Leukemia
If you haven't been hearing thumps during powering on/off, then generally the other failure mode for losing multiple speakers at the same time is overdriving them while the system is in use --- that would be pretty hard to not notice the moment it happens, so I would lean towards it being more likely the amplifier is having issues rather than the speakers.

Mixing console is also unlikely, though you can try driving the system from different outputs on the mixer and see if that does anything. Looks like that amplifier has built-in Bluetooth. You could also try pairing to it and bypassing the mixer altogether. If you drive it over Bluetooth and hear the same distortion, it's either the amplifier or the speakers.
 

RonHebbard

Well-Known Member
Premium Member
Awesome, thanks for this.
We don't get a thump at all, we've been pretty consistent with proper power on and off protocols. General consensus says amplifier, I've got a small mixer and other speakers we will start doing some testing with this week!
@machaelaburt Amplifiers: ON LAST & OFF FIRST; ALWAYS!!!
Toodleoo!
Ron Hebbard
 

TimMc

Well-Known Member
Premium Member
Hi Dave,
Thanks for the quick response. The amp is a Pyle PTA 1000, I'm getting consistent signal readings from it and from the board. The speakers, I have no idea what model they are, but they have little "EV" insignia on the bottom. I don't have a crossover or processor currently installed.
I will reach out to my music colleagues and see if we can find another amp to do some testing with. Thanks!
So by "consistent readings" you mean "the meters on the amp move proportionately to the meters on the console"? If so... has anyone been futzing with anything on the back of the amplifier? Are you using the XLR or 1/4" inputs? Speakers hooked up using the binding posts or the SpeakOn outputs? Are there any "adapters" in the path between console outputs and amp inputs?
 

FMEng

Well-Known Member
Fight Leukemia
That amp has a bluetooth receiver in it, so it could be set to that source. Make sure the button on the far, right side is OUT. Also check that bridging mode switch on the back is set correctly.
 
Hi friends,
Thanks for all the troubleshooting tips-
Here's where we're at:
I've run my phone into the amp via bluetooth and run a separate, passive speaker through the amp with the same results- quiet, distorted, fuzzy sound. I don' t have a second amp currently to diagnose speakers, but from what I've gathered from everyone, the Pyle we had purchased is, well... a pile.
Recommendations for better, not-going-to-break-the-bank-rural-high-school amplifiers?
 

almorton

Well-Known Member
Where does one start? Do you have a supplier you normally use?


Depending on budget, you could look at QTX, QSC, Crest, Crown, EV, Lab Gruppen ... but the cost might be going up too quickly for you. In UK/Europe I'd suggest one or two lower cost alternatives like Behringer or t.Amp but I'm not sure they're available in the States, which doesn't help you.
 

DrewE

Well-Known Member
It's impossible to recommend a specific amplifier without knowing what speakers you're driving. That said, I've had some good experiences with both Crown XLI series and QSC GX series amplifiers. Both are fairly basic, low-end models made by well-known and well-respected companies. Both are not especially well-suited for driving multiple speakers per channel (their minimum impedance specifications are not too low), but would likely be perfectly fine for your application, where they're dedicated to a single speaker per channel, and should last for many years. Either would be a definite step up from the Pyle amp. Figure maybe $300-$500+ or so new, depending on your power output requirements.

(I have seen a few GX amplifiers where the power switch got somewhat flakey after a good bit of use over several years. It's a standard sort of snap-in rocker switch, not at all hard to replace by someone reasonably adept at electronics repair, no soldering required.)
 
It's impossible to recommend a specific amplifier without knowing what speakers you're driving. That said, I've had some good experiences with both Crown XLI series and QSC GX series amplifiers. Both are fairly basic, low-end models made by well-known and well-respected companies. Both are not especially well-suited for driving multiple speakers per channel (their minimum impedance specifications are not too low), but would likely be perfectly fine for your application, where they're dedicated to a single speaker per channel, and should last for many years. Either would be a definite step up from the Pyle amp. Figure maybe $300-$500+ or so new, depending on your power output requirements.

(I have seen a few GX amplifiers where the power switch got somewhat flakey after a good bit of use over several years. It's a standard sort of snap-in rocker switch, not at all hard to replace by someone reasonably adept at electronics repair, no soldering required.)



Thanks! Probably should have led with that:
 

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