AVS Forum banner
Status
Not open for further replies.
1 - 16 of 16 Posts

·
Registered
Joined
·
861 Posts
Discussion Starter · #1 ·
I'd like to hear from anyone who has had bass-shakers/tactile transducers fail.


It seems soundtracks are getting more extended in their bass impact and depth.Are bass shakers failing due to the massive power required to reproduce these bass heavy scenes?


Does anyone have any bass shaker failures/burn-ups or disasters they can share?


Max Christoffersen
www.audioenz.co.nz
 

·
Registered
Joined
·
1,321 Posts
I have a Clark Synthesis 329. I was driving it with a cheap Parts Express subwoofer amp. The transducer blew after about a year and a half. I sent it back to Clark and they fixed it (out of warrentee). The fixed unit failed after about a year and Clark fixed it for free (I just paid S&H which was enough).


After the second failure I talked with Clark and they suspected that the cheap sub amp was clipping, sending lots of high frequency noise into the tranducer causing it to burn out. I checked and it was pretty easy to drive the sub amp to clip so when I could afford it I bought the amp Clark recommened -- the AudioSource Amp 3 giving a bridged mono power of 400 watts.


I got the newly repaired transducer back from Clark about 5 weeks ago. Worked like a charm. The Amp 3 had lots of balls. It sounded good. Shook the room wonderfully. Twister in DTS takes on a whole new meaning!


But just 3 weeks after getting the transducer back, I blew it again! Admittedly it was probably my fault because I was trying to tune the room and had given it a solid 20 Hz sine wave, but it blew before I had a chance to realize there was a problem. That was two weeks ago, and I'm still so pissed that I haven't taken it out to look at it. Maybe today.


I'm going to see if I can open it here and get someone locally to rewind it. It costs almost $100CDN to ship the transducer to Clark and back, and I'm sure they won't fix it for free this time.


Does anyone have a circuit I could build or buy that I could put on the amp output to shunt all frequencies above 5 kHz into a dummy load rather than allowing them to blow the transducer. I love the shake, but the cost of repairing it every couple of weeks is starting to loose its charm.


Mike
 

·
Banned
Joined
·
9,999 Posts
Attached show the specifications for the Clark Synthesis 329 tactile transducer. I'm not 100% certain how one is suppose to be interpreting this chart, but should one be using the Overall frequency range for the Input signaling and the Tactile frequency range as what the transducer will Output?


If this is how one should interpret it then I would say you are not doing anything wrong, unless you are feeding the Input with an amplified signal instead of line-level signaling. Also, since you are using the recommended amplifier, make sure its bridged for 4-ohm operation.


I would think that as long as you are feeding the transducer 400W into 4-ohms within the specified frequency range using the recommended amplifier any failure is on the transducer's fault, or the manufacturer's fault for the specified allowances.
 

·
Banned
Joined
·
9,999 Posts
Oops, I should have said that 'as long as you are not feeding the amplifier with an amplified signal ... yadda, yadda, yadda.'
 

·
Registered
Joined
·
475 Posts
Been using the Auras with the included 35 watt Aura amps set at 4-5 on a scale of 10. More than enough shake and never a problem.
 

·
Registered
Joined
·
316 Posts
Quote:
Does anyone have a circuit I could build or buy that I could put on the amp output to shunt all frequencies above 5 kHz into a dummy load rather than allowing them to blow the transducer. I love the shake, but the cost of repairing it every couple of weeks is starting to loose its charm.
How are you driving it? (line level inputs to the power amp or speaker level - full range or LFE output or what).


It would make more sense to filter before the power amp than after it, you could make a simple circuit with 2 resistors and a capacitor to make a low pass filter.
 

·
Registered
Joined
·
161 Posts
I drive my Auras with a cheap $50 car audio amp. Not a problem so far. :)


Eric
 

·
Registered
Joined
·
165 Posts
Eric,

How are you powering the car audio amp?
 

·
Registered
Joined
·
161 Posts
I am using a generic 12V power supply than can handle about 5A of current -- plenty for this application. A 12V wall transformer would probably not have the current necessary to power the amp...so I'd advise against that.


Eric
 

·
Banned
Joined
·
9,999 Posts
You know, I just bought two-pair of these Bass Shakers from PE for $30/pair. Are these the same one's that Smart Home is charging $110/pair for?
 

·
Registered
Joined
·
161 Posts
Yeah, I've seen places charging like $110 or so for these things. I got mine from hTRADE for about $30.
 

·
Registered
Joined
·
1,321 Posts
Quote:
Originally posted by efball
How are you driving it? (line level inputs to the power amp or speaker level - full range or LFE output or what).
Pre-outs from the Denon receiver go into a RS mixer, the output of the mixer goes to a Berhinger DSP 8024 equalizer, which goest to the Audiosource AMP 3, to the transducer. It's all line level up to the AMP 3 and none of it is clipping (levels are all OK).

Quote:
Originally posted by efball
It would make more sense to filter before the power amp than after it, you could make a simple circuit with 2 resistors and a capacitor to make a low pass filter.
I can easily turn down high frequencies with the eq. But that's not the problem. I'm looking for some way to shunt the high frequencies generated when the amp clips. Those would be very high power and a simple RC circuit might go up in flames. It would also be nice if a light went on to show that clipping was happening to ensure I turn things down.


Mike
 

·
Registered
Joined
·
316 Posts
Quote:
I can easily turn down high frequencies with the eq. But that's not the problem. I'm looking for some way to shunt the high frequencies generated when the amp clips. Those would be very high power and a simple RC circuit might go up in flames. It would also be nice if a light went on to show that clipping was happening to ensure I turn things down.
First read this article talking about clipping and damage to speakers: http://www.rane.com/note128.html


You wouldn't need to shut the high frequencies to an alternate load (like a crossover network), just make a low pass filter that is high impedence at high frequencies (like half a crossover network). The transducer would be isolated and the amp would see no load at high frequencies. I'm sure there are webpages out there telling you how to design speaker crossovers, and this one doesn't have to be too fancy, but it will require some huge - probably hand wound - inductors.


I'm using the amp 5.2 which does have a clipping light, but it's extremely rare that it comes one. The Clark Platinum is rated 135 watts. The Audio Source amp 5.2 is rated 150 watts into 4 ohms the the clipping light is supposed to come on when it is within 3dB of clipping, so that's when it's running at 75 watts output power (so some flickering of the light is safe). I guess if I had the 329 model instead of the Platinum I'd have to crank up the power a lot more.


Your amp 3 is rated 240 watts/channel into 4 ohms or 400 watts bridged. You are probably just blowing the snot out the the Clark unit with clean unclipped power.


Rather than making a low pass filter, which won't protect against too much un-clipped power I'd recommend making a level detector that flashes whenever you go above some pre-set power level.


A quick google search found a couple web pages showing how to make a LED peak level meter, and I'm sure there are many others:

http://www.4qdtec.com/avu.html

http://wiredworld.tripod.com/tronics/audio_level.html


voltage = the square root of (power * resistance).


The clark unit is 4 ohms so you can calibrate the detector to whatever voltage or power level you want to. 135 watts into 4 ohms comes out to 23 volts. 20 volts would be a safer limit (100 watts).
 

·
Registered
Joined
·
6,436 Posts
Max, when you say fail, do you mean that it doesn't work at all, or that it now makes a strange rattling sound?


I have some cheap shakers that are similar to the Aura's, and have no casing as such - you can see the support spiders.


A couple of them (I have 8 including two spares) had the spider come adrift from the casing, and all it needed was some silicon rubber after fixing them back into place, and they've been fine ever since. Super glue and silicon may be a better solution, as the edge that goes into the casing doesn't move like the rest does.


I'm not using the Aura amps for mine (I believe you are), so in my case I don't know if they were just poorly made, or if the mass hit the spider and dislodged it from the casing (from overdriving).


Anyway, I just thought my experience may be of some use.


Gary.
 

·
Registered
Joined
·
861 Posts
Discussion Starter · #16 ·
Gary,


I mean failure requiring repair.


I use four Buttkickers, two aura Pros, two Aura cushions and a Clark Synthesis Platinum in my system. I'm interested to know which of these has proved to be the most durable and conversely the most unreliable.


Your Auras 'coming loose' are the first I've heard of from Aura, mine have been fault free and they are driven hard from a dedicated AMC 5 channel amp and AudioControl Richter Scale EQ.


I have my some concern about the increasing depth and power coming from film soundtracks and suspect that there will be increasing strain placed on tactile transducers, resulting in increasing reports of outright failure and experiences similar to your own with the smaller Aura units.


The main reason for my query is to compile the experience of those who have had any form of failure and to document which of these units appears to be more prone to performance problems with the 'new-bass' found on soundtracks like Resident Evil.



Max Christoffersen
www.audioenz.co.nz
 
1 - 16 of 16 Posts
Status
Not open for further replies.
Top