Power problem with Def Tech BP9040

J

Jmichaels001

Enthusiast
I have a BP9040 with A90 topper and the power light in the back, and the lighted D in the front aren't lit. The power cord was plugged into the back of my Cyber Power and I was running the speaker large with no LFE. The rest of the speakers on the tower do seem to be working. I have hardly used these things and purchased new in box on eBay last November. Power never over 12 O'clock. Any ideas? Is there a fuse? Is the amp blown? Am I screwed with regard to warranty work?
 
everettT

everettT

Audioholic Spartan
Does the manual indicate a fuse? Did you try a different outlet? FWIW it's usually not advised to plug amps into power conditioners or regulators and I'm not sure what Cyber power is. Also try running the lfe in and the speaker large + lfe and see if the amp senses the signal.

As for your warranty, just call and give them the serial number and see how they wanna handle it, if you did blow the amp.
 
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J

Jmichaels001

Enthusiast
I did try a different outlet. No mention of a fuse in the tiny owners manual but thought with a powered subwoofer it might have one. Cyberpower is like an APC. Sine wave power battery backup
 
everettT

everettT

Audioholic Spartan
I did try a different outlet. No mention of a fuse in the tiny owners manual but thought with a powered subwoofer it might have one. Cyberpower is like an APC. Sine wave power battery backup
A quick search revels that amp blowing is common FYI. I suggest contacting them as it's a known issue.
 
TLS Guy

TLS Guy

Seriously, I have no life.
I have a BP9040 with A90 topper and the power light in the back, and the lighted D in the front aren't lit. The power cord was plugged into the back of my Cyber Power and I was running the speaker large with no LFE. The rest of the speakers on the tower do seem to be working. I have hardly used these things and purchased new in box on eBay last November. Power never over 12 O'clock. Any ideas? Is there a fuse? Is the amp blown? Am I screwed with regard to warranty work?
Take the amp out, and open it up. If there is a blown fuse, replace it once. It will probably blow again, as fuses usually blow for a reason.

You should not power a power amp from a UPS unit, like that Cyber power.

Those class D amps, are not easily fixed, so you probably will need to search for a replacement amp, if you can find one.
 
J

Jmichaels001

Enthusiast
Contacted Def Tech Support. There is a fuse but swapping them didn’t do anything. So they are going to send me a new amp except they are currently out of stock. I am so pissed. I should have listened to others but my previous pair never gave me problems.
 
TLS Guy

TLS Guy

Seriously, I have no life.
Contacted Def Tech Support. There is a fuse but swapping them didn’t do anything. So they are going to send me a new amp except they are currently out of stock. I am so pissed. I should have listened to others but my previous pair never gave me problems.
Are the original fuse and the replacement fuse now blown?
 
J

Jmichaels001

Enthusiast
I removed the fuse from the left speaker that wasn’t working and tried the fuse from the right speaker but it didn’t seem to do anything. I was able to place the fuse back into the right speaker and that speaker still works so it didn’t blow that fuse.
 
TLS Guy

TLS Guy

Seriously, I have no life.
I removed the fuse from the left speaker that wasn’t working and tried the fuse from the right speaker but it didn’t seem to do anything. I was able to place the fuse back into the right speaker and that speaker still works so it didn’t blow that fuse.
That is really strange. Usually when amps blow up like this, the fuse blows. Are you certain you don't have a bad power cord?

It seems Def Tech amps have a horrible reputation I find after doing some research. There are pictures on the Net. of those amps, having a bank of resistors all burnt out. I suspect that is effect though rather than the primary cause of failure. It seems those resistors seem to burn before the fuse does. I suspect you are wasting your time with some Chinese junk amps.

My advice is to use the top ends, and use stand alone subs, rather then fixing those speakers.
 
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J

Jmichaels001

Enthusiast
I did try a different outlet but haven’t tried swapping power cables. The fuse may be blown. I didn’t try inserting it into the working speaker. I just tried taking the good one and putting the speaker that wasn’t working snd still no lights
 
everettT

everettT

Audioholic Spartan
I did try a different outlet but haven’t tried swapping power cables. The fuse may be blown. I didn’t try inserting it into the working speaker. I just tried taking the good one and putting the speaker that wasn’t working snd still no lights
Did you try setting the speakers to small and using the subwoofer output from the AVR out of curiosity?

As noted by me and others, the amp failure is common and replacement has no guarantee of not failing soon again. There is one guy on AVS that replaced the amp twice already, and a couple of drivers as well, tweeters IIRC, which means you might always be having issues with these particular speakers.

You can purchase good subs and use the speakers without their built in woofer until you're ready to upgrade is another option.
 
J

Jmichaels001

Enthusiast
I did recently purchase an SVS SB-2000 Pro. But as soon as I get this repaired I’m going to look into selling them and getting something without a built in powered sub. I did like the Atmos being built into the speakers. Currently have a CS-9060 and four SR9080 surrounds. Anything you would recommend I look at?
 
everettT

everettT

Audioholic Spartan
I did recently purchase an SVS SB-2000 Pro. But as soon as I get this repaired I’m going to look into selling them and getting something without a built in powered sub. I did like the Atmos being built into the speakers. Currently have a CS-9060 and four SR9080 surrounds. Anything you would recommend I look at?
Without a budget its hard to start that process. Considerations to take into account, distance from the main listening position to the speaker, how loud you like to listen, is your current AVR sufficient to drive a particular speaker and overall deminson of the room, including if it opens to another area.

Also, it might be a good idea/time to place the Atmos/height speakers in there correct locations, you'll be amazed at the difference.
 
J

Jmichaels001

Enthusiast
Limitations prevent me from mounting height speakers. For LCR my budget would be $2500. Mostly movies. Seats are 11’ from speakers closed room 14’ x 17’ with 10’ ceilings. Tv centered on 17’ wall
 
TLS Guy

TLS Guy

Seriously, I have no life.
Limitations prevent me from mounting height speakers. For LCR my budget would be $2500. Mostly movies. Seats are 11’ from speakers closed room 14’ x 17’ with 10’ ceilings. Tv centered on 17’ wall
It would be best if the TV was centered on the 14' wall. Active speakers containing amps are the way forward. Def Tech amps a junk, but there are many that are excellent with envious reliability. For instance class D amp modules from Hypex and Purifi have an absolutely sterling reputation for high quality and reliability.
There are huge advantages to speakers with active speakers and crossovers.
 
everettT

everettT

Audioholic Spartan
I think more like "getting something without a built-in amp".

The built-in amps are usually at fault, not the subwoofers.
Not with all manufacturers FWIW. There are many powered speakers that work much better then the reliability of DefTech's. Powered speakers are fine, the passive/powered by hybrids, not so much.
 
Verdinut

Verdinut

Audioholic Spartan
The powered subs which use a cooler Class D amplifier are the ones to prioritize.
 
TLS Guy

TLS Guy

Seriously, I have no life.
I think more like "getting something without a built-in amp".

The built-in amps are usually at fault, not the subwoofers.
The world is heading towards active speakers, for a huge number of good reasons.
 
D

Dennis white

Audiophyte
I have a BP9040 with A90 topper and the power light in the back, and the lighted D in the front aren't lit. The power cord was plugged into the back of my Cyber Power and I was running the speaker large with no LFE. The rest of the speakers on the tower do seem to be working. I have hardly used these things and purchased new in box on eBay last November. Power never over 12 O'clock. Any ideas? Is there a fuse? Is the amp blown? Am I screwed with regard to warranty work?
POTENTIAL SOLUTION:

I found this thread because I was experiencing the same problem. I called their customer support line which I found very attentive and helpful. The guys name was Angelo particularly shout-out to him.
we went through a thorough troubleshooting process and I asked if it could be something to do with the fuse and he said that given that there was a solid red light on the back of the unit, but that would indicate that the fuse was not blown.
I was curious anyway and I removed the fuse from the unit. It’s solid white so I couldn’t see if it had been blown. I put the fuse back in the unit, and the problem was solved immediately.

A person speaking with customer support, might not be inclined to be curious about something like this if they’re being told that they couldn’t possibly be the problem, and I don’t the customer service representative for that, he’s just reading from a company script for troubleshooting.

Anyway, I took some time to join this forum just so I could share this information in hopes that it might be helpful to someone experiencing the same trouble. Because most of the things that I have read on the subject implies that you have to place The amplifier, and that these units are somewhat notorious for that issue.

One last thing that I will share is that Angelo entirely sure that those parts were even available anymore, which means that when or if these speakers do an amplifier it might not be possible to find a replacement so I’m almost thinking about buying two replacement amplifiers in case I need one in the future


Yours in music,

Dennis
 

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