Hi all,
So a while back I picked up two speakers second hand, from what I can work out they're custom built and probably minimum 10 years old. Recently had a party and a drunk friend turned on the mic mid-set, massive feedback loop and tweeter on one speaker completely gone.
Have opened it up and was hoping the tweeter would have a model No. or something but the entire loudspeaker seems to be unbranded. Am wondering what the best way for me to determine a replacement would be? I'm like 90% sure that each loudspeaker is 8ohm impedance and 300W but thats all the information I have.
I've attached pictures of the broken tweeter and the wiring on the crossover, also something that has caused confusion to the few people I've shown it to. So far have not managed to work out what the use of the jack inputs is, as have just been hooking it up to amp using speaker wire.
Also while here, as there was a huge surge due to mic and damage to speakers, is there a chance that the amp could be damaged too? and if so is there any way to check? from what I could work out through testing it sounds pretty ok.
So a while back I picked up two speakers second hand, from what I can work out they're custom built and probably minimum 10 years old. Recently had a party and a drunk friend turned on the mic mid-set, massive feedback loop and tweeter on one speaker completely gone.
Have opened it up and was hoping the tweeter would have a model No. or something but the entire loudspeaker seems to be unbranded. Am wondering what the best way for me to determine a replacement would be? I'm like 90% sure that each loudspeaker is 8ohm impedance and 300W but thats all the information I have.
I've attached pictures of the broken tweeter and the wiring on the crossover, also something that has caused confusion to the few people I've shown it to. So far have not managed to work out what the use of the jack inputs is, as have just been hooking it up to amp using speaker wire.
Also while here, as there was a huge surge due to mic and damage to speakers, is there a chance that the amp could be damaged too? and if so is there any way to check? from what I could work out through testing it sounds pretty ok.
Attachments
The jack sockets will be wired in parallel. This is to allow you to daisy-chain a second loudpeaker cabinet. i.e. amp to one jack socket - other jack socket to second speaker.
Have you more pictures of the tweeter? It looks like a piezo tweeter.
The amp is unlikely to be damaged if it sounds OK.
The amp is unlikely to be damaged if it sounds OK.
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It´s a very dead cheap (5 bucks) Piezo horn driver.
Get a new one and replace it.
Goldwood GT-400CD Bullet Piezo Horn Driver
Jack inputs are the same as the wired ones, but expecting standard 6.35mm guitar type plugs and cables.
The blue capacitor and white ceramic resistor are a *crude* crossover, to protect tweeter from low frequencies, "should work fine.
Worst case replace it with same components..
Now if a drunk "performer" puts microphone inches away from speaker, high frequency squeal will kill it.
Get a new one and replace it.
Goldwood GT-400CD Bullet Piezo Horn Driver
An externally hosted image should be here but it was not working when we last tested it.
Jack inputs are the same as the wired ones, but expecting standard 6.35mm guitar type plugs and cables.
The blue capacitor and white ceramic resistor are a *crude* crossover, to protect tweeter from low frequencies, "should work fine.
Worst case replace it with same components..
Now if a drunk "performer" puts microphone inches away from speaker, high frequency squeal will kill it.
monacor.co.uk carry a range of replacement PA piezo tweeters.
PA tweeters and horn tweeters - Speaker Components - Commercial & PA Speakers - Monacor | Monacor UK
This driver is the same as the one JMF has just posted:
MPT-142 | Monacor UK
PA tweeters and horn tweeters - Speaker Components - Commercial & PA Speakers - Monacor | Monacor UK
This driver is the same as the one JMF has just posted:
MPT-142 | Monacor UK
by doing this would it change the impedance on that amp channel or is it literally as easy as plugging another speaker in with no change? pretty sure the guy might have said he used to daisy chain it with subs actually, I'm assuming they would also need to be rated 300W?
thanks for the fast reply
Amazing thanks everyone, this forum is amazing.
Was actually thinking of using this as an opportunity to upgrade the tweeters as found these a bit sharp on the higher frequency drum sounds, anyone got a good recommendation that would be able to just do a straight swap?
Was actually thinking of using this as an opportunity to upgrade the tweeters as found these a bit sharp on the higher frequency drum sounds, anyone got a good recommendation that would be able to just do a straight swap?
The speakers would be working in parallel, so two 16 ohm speakers would result in an 8 ohm load and two 8 ohm speakers would result in a 4 ohm load. If it's a valve amp, change the impedance selector accordingly. If it's a solid state amp, make sure it can work safely into the new load.
You could add a passive sub in this manner.
A similar power handling to the original cab is good idea.
You have to match the sub's impedance to that of the original cabinet (2 x 8 ohm in parallel gives 4 ohm) and make sure your amplifier is comfortable working into a 4 ohm load.
Biggest problem may be matching up the sensitivities (dB/W) of the original cab and the sub. Best to get an audition before parting with your cash!
JMF may have more to say about the last point, as this is his stock in trade. 😎
It is possible to make a piezo tweeter sound less harsh and spitty, as well as make it a bit more reliable.
If you tell me the value of the capacitor on your terminal panel i.e. its capacitance in µF (probably in the order of 4.7µF), I'll give you a simple fix. 😉
Am currently in the process of designing and building my first sub, so will probably just wire both loudspeakers from channel 1 and have the sub on its own channel.
Also have a quick question regarding the build, not sure if I should start a new thread though, just was wondering whether I have to build a crossover into the sub if my amplifier has DSP so I can just route low frequencies to one channel. is this just a really stupid idea? (finding crossovers very confusing)
Also, are there any really good websites for speaker parts in the UK, have done a fair amount of searching but from what I can work out we have no equivalent site to parts express? have always ended up going through eBay so far
All the Monacor piezo tweeters to which I linked have a maximum peak music power rating of 115W on an 8 ohm system and 225W on a 4 ohm system.
Is there a problem with the piezo horn driver we recommended?
Blue Aran is the site for PA components: Blue Aran - The UK's no.1 Loudspeaker Component Stockist
Also check out Willys HiFi: UK Speaker Drivers And Spare Parts Specialist
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no sorry have gone for that now, was originally hoping to upgrade the sound a bit but didn't realise what a piezo was and that they seem to be all pretty much the same.
Thanks so much for all the help Gulu, sorry for being a bit annoying am a newbie to forums and diy projects so still finding my feet... trying to get better at researching properly before asking which I can see can be frustrating at times.
