Whats broke here?

jeep jones

Active Member
I'm trying to pin down an issue with a pair of ESS AMT 2's. When I put my meter on the main speaker terminals, one reads 8.2 and the other 4.7. Crossover issues?

I am pulling and testing individual drivers this weekend, but what would be the correct reading? Are thes 8 ohm or 4 ohm speakers (hoping they are 8)? I have yet to find specs anywhere on this specific model.

Any info would be appreciated...
 
4.7 ohms DC resistance is typical for an 8 ohm AC impedance speaker. Probably something open in the one reading 8.2
 
I'd also be leaning towards a driver issue ... Check those first ..
 
The filter capacitors on the tweeter leg of the crossover circuit block DC from the meter, so your measurements are essentially of the DC resistance of the woofer circuit. Measure the woofers first. If they're equal, do a resistance check between the positive input terminal on the back of the speaker and the end of the wire that connects to the positive terminal on the driver (not connected to the driver). It should read 0 (or extremely close).
What prompted this, anyway? Is there a problem with the sound?
 
Ok...so sounds like the concensus is a driver issue. To answer a couple of your questions...yes, one of the woofers has no surround and is not an original driver. sound wise, I think it sounds as expected with a woofer that has a toasted surround.

My main concern is my amp. I am running these as my B set and my amp (pioneer SA-8500) requires 8 ohm or greater when running both A and B speakers. I was hoping that when tepaired, they were 8 ohm so I could run them in that A+B config...
 
Ok...so sounds like the concensus is a driver issue. To answer a couple of your questions...yes, one of the woofers has no surround and is not an original driver. sound wise, I think it sounds as expected with a woofer that has a toasted surround.

My main concern is my amp. I am running these as my B set and my amp (pioneer SA-8500) requires 8 ohm or greater when running both A and B speakers. I was hoping that when tepaired, they were 8 ohm so I could run them in that A+B config...

I think that you're hosed. I believe that the 2 is rated at 4 ohms overall. I've run two pair of 4 ohm speakers (ESS AMT-3 and ADS L-1230) on a Denon integrated amp where I shouldn't have without incident, but it's a risk.
I wonder if you could pull your pre-out/power amp in jumper and replace it with a splitter (RCA Female to (2) RCA Males) with the males plugged into the Pioneer and the female having an RCA patch cord going to a separate power amp with a variable GAIN to balance everything?
If you didn't mind having to operate two volume controls, it would be cheap and easy to join the tape out on the Pioneer to any line level input on another integrated amp or receiver. Either way, it's preferable to shortening the lifespan of your Pioneer.
 
Yeh, Pork, thats what I feared. I'm already running a second amp on my tape out as you described that powers all of my home speakers. I won't risk damage to my amp, so when these speakers are back on their feet, I will probably just run them exclusively on the A set and call it a day.

I'll post when I've got them finished.

Thanks for all the input guys! Much appreciated!
 
Yeh, Pork, thats what I feared. I'm already running a second amp on my tape out as you described that powers all of my home speakers. I won't risk damage to my amp, so when these speakers are back on their feet, I will probably just run them exclusively on the A set and call it a day.

I'll post when I've got them finished.

Thanks for all the input guys! Much appreciated!

Don't forget the pics. (I never do).

IMG_0313.JPG
 
Ok...so sounds like the concensus is a driver issue. To answer a couple of your questions...yes, one of the woofers has no surround and is not an original driver. sound wise, I think it sounds as expected with a woofer that has a toasted surround.

My main concern is my amp. I am running these as my B set and my amp (pioneer SA-8500) requires 8 ohm or greater when running both A and B speakers. I was hoping that when tepaired, they were 8 ohm so I could run them in that A+B config...


That's NOT your only problem. Your speakers will never be balanced with each other. One of your woofers is incorrect. The impedance of the woofer is significant in the low pass filter part of your xover.

I seriously doubt whoever replaced the woofer made the necessary xover changes and even if they did, it would still consume more power and put out more SPL in just the low frequencies than it's mate.

You really need to get correct replacement woofers.

Regards,
Jerry
 
Jerry, you are spot on. When I pulled the drivers, one was 8 ohm and the other (original) was 4 ohm. I know the PO had a local shop do some work on them. I had hoped they had done a better job at selecting a replacement. Guess not... Fortunately it is also the one that the surround toasted on, so I was replacing it anyway. It still tests good, so I will put it on the shelf for a future project.

20170317_202352.jpg
 
Jerry, you are spot on. When I pulled the drivers, one was 8 ohm and the other (original) was 4 ohm. I know the PO had a local shop do some work on them. I had hoped they had done a better job at selecting a replacement. Guess not... Fortunately it is also the one that the surround toasted on, so I was replacing it anyway. It still tests good, so I will put it on the shelf for a future project.

View attachment 890418



I am corresponding with a guy that is refurbing AMT1's with a 10" Pro woofer with 96 db sensitivity in hopes of bridging the infamous ESS midrange gap..The bad is, he'll be lucky to hit 50 Hz, meaning he'll be using a subwoofer. Do you want to be part of that messaging thread to pick up potential driver inspiration?
 
I am corresponding with a guy that is refurbing AMT1's with a 10" Pro woofer with 96 db sensitivity in hopes of bridging the infamous ESS midrange gap..The bad is, he'll be lucky to hit 50 Hz, meaning he'll be using a subwoofer. Do you want to be part of that messaging thread to pick up potential driver inspiration?

Definately
 
Definately
If you're patient or bored, the first lengthier thread ("Would you be willing to discuss my AMT1's with me?") may provide a bit of background, but after reviewing it again, It's pretty much me rambling on too little sleep. The second thread ("Crossover for ESS Heil") is a continuation. I'll insert a summation there about the Faital 10" 4 ohm woofer.
 
If you're patient or bored, the first lengthier thread ("Would you be willing to discuss my AMT1's with me?") may provide a bit of background, but after reviewing it again, It's pretty much me rambling on too little sleep. The second thread ("Crossover for ESS Heil") is a continuation. I'll insert a summation there about the Faital 10" 4 ohm woofer.

Interesting read. I'm still very much on the learning end of speaker builds, so its all great info for me.
 
Throw that taiwan driver in the trash please! Not worth waisting foam on...Let alone time

Actually, that "Taiwan" woofer is a Pioneer. Not a bad driver, in the right application.

Those were EXTREMELY common DIY drivers back in the 1980s. Heck, I probably used a dozen or more of them, myself.

I'd bet somebody out there needs that, to replace one somewhere...

Regards,
Gordon.
 
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