I recently acquired this sub inexpensively and on powering up, it was DOA. It sounds like the power relay inside is just continuously cycling.
So, I removed the screws on the panel in back, and Voila! Nothing!
The amplification unit doesn't come out. It rocks a little, but won't come out. I've looked at it 9 ways to Sunday and still can't extract the amplifier.(Yes, this is a little embarrassing) I've removed the feet, peeled back a portion of the label covering the faceplate which has revealed no hidden screws, & rocked it side to side till I'm blue in the face. It won't come out. Anyone ever played around with one of these??
This may sound like asking for free tech support, but I am an avid audiophile who has great interest in audio as a hobby with the goal of refurbishing some older stereo equipment.
I'm an old guy now, so I have the time
So, I removed the screws on the panel in back, and Voila! Nothing!
The amplification unit doesn't come out. It rocks a little, but won't come out. I've looked at it 9 ways to Sunday and still can't extract the amplifier.(Yes, this is a little embarrassing) I've removed the feet, peeled back a portion of the label covering the faceplate which has revealed no hidden screws, & rocked it side to side till I'm blue in the face. It won't come out. Anyone ever played around with one of these??
This may sound like asking for free tech support, but I am an avid audiophile who has great interest in audio as a hobby with the goal of refurbishing some older stereo equipment.
I'm an old guy now, so I have the time
Yes, Inside I found only the usual acoustic damping material. The amp is segregated in its own little partition at the bottom with only the drivers wires penetrating from it. The hole is sealed with glue where the wires emerge.
At this stage, the only thing I can think is that these glued wires may be the only thing retaining the amplifier, but it's possible There's some trick to removing the back cover which I just don't know of.
Thanks for the help though, mRgSr!
At this stage, the only thing I can think is that these glued wires may be the only thing retaining the amplifier, but it's possible There's some trick to removing the back cover which I just don't know of.
Thanks for the help though, mRgSr!
Should definitly be a sticky gasket.
There are no screws inside. I have a module from the Linn Sizmik 10.25.
This sub has no servo control.
But ist uses a switchmode (probably downtracking) powersuply.
Producing around 800w a 8Ohm
4Ohm it is current limiting near 500w
I use one of these for a big corner loaded horn-subwoofer in a bar and wanted to replace it with a newer and stronger class d modul.
After I mesured the new modul , I hooked up the Linn modul to the resistors and was realy surprised about the output power.
The newer modul made only a little more at 8Ohm , so the linn module is still working there.
Only bad thing is the tiny heat sink and the noisy fan, and that there are different descriptions for the parameter settings.
There are no screws inside. I have a module from the Linn Sizmik 10.25.
This sub has no servo control.
But ist uses a switchmode (probably downtracking) powersuply.
Producing around 800w a 8Ohm
4Ohm it is current limiting near 500w
I use one of these for a big corner loaded horn-subwoofer in a bar and wanted to replace it with a newer and stronger class d modul.
After I mesured the new modul , I hooked up the Linn modul to the resistors and was realy surprised about the output power.
The newer modul made only a little more at 8Ohm , so the linn module is still working there.
Only bad thing is the tiny heat sink and the noisy fan, and that there are different descriptions for the parameter settings.
So, I got it out!
On inspection, it looks like there's a rectifier which got a little toasty.
Haven't pulled the board yet to test it as it's going to get involved.
It looks like the only thing holding the board in , besides screws, are the heat sinks attached to the large fan-cooled heat sink. I'd prefer to remove the two together as a unit and not have to detach the component heat sinks where they bond to the main.
I haven't tried yet since there's also a potential issue with the clamps holding the transistor heat sinks to the main heat sink.
I'm guessing they're torqued to a certain spec. so as not to damage the chip.
Just not too sure & I don't have a torque wrench that small.
I'll probably just wing it eventually.
On inspection, it looks like there's a rectifier which got a little toasty.
Haven't pulled the board yet to test it as it's going to get involved.
It looks like the only thing holding the board in , besides screws, are the heat sinks attached to the large fan-cooled heat sink. I'd prefer to remove the two together as a unit and not have to detach the component heat sinks where they bond to the main.
I haven't tried yet since there's also a potential issue with the clamps holding the transistor heat sinks to the main heat sink.
I'm guessing they're torqued to a certain spec. so as not to damage the chip.
Just not too sure & I don't have a torque wrench that small.
I'll probably just wing it eventually.
Hmmm, Well I've been looking at this subwoofers amp for a while now.
It wasn't the rectifier.
The power supply is in protect mode.
it uses a SG3524BDW chip which shows voltage difference between Inv + noninv inputs, so I guess thats the thermistor feed.
thermistor reads 3.58K.
Schematic anyone?
It wasn't the rectifier.
The power supply is in protect mode.
it uses a SG3524BDW chip which shows voltage difference between Inv + noninv inputs, so I guess thats the thermistor feed.
thermistor reads 3.58K.
Schematic anyone?
Well, Linn won't release the schematic.
Oh Chris, the reason I was concerned about the transistor screws is that the screws don't pass through the provided screw hole on the heat sink of the transistor, but rather, through a large plate designed to traverse two transistor cases with the screw passing through it and midway between two transistors to the amplifier case.
so the plate is actually clamping the plastic case of two transistors.
I'm sure if I tighten them too much, I'll break the case.
Thanks though!
Oh Chris, the reason I was concerned about the transistor screws is that the screws don't pass through the provided screw hole on the heat sink of the transistor, but rather, through a large plate designed to traverse two transistor cases with the screw passing through it and midway between two transistors to the amplifier case.
so the plate is actually clamping the plastic case of two transistors.
I'm sure if I tighten them too much, I'll break the case.
Thanks though!
Sorry to resuscitate an ancient thread, but I now have two dead 221s. One shows open circuit across the driver terminals, so presumably that's a melted voice coil. Getting inside the driver looks tricky as it has a kind of elastic gauze sock over its rear, all sealed in. Does anybody know what the drive unit is? One of mine says 'SPKR 050/3 7H4328D'.
I blew the other one a few days ago by knocking my cantilever against the edge of a record with the volume way too high. I would be willing to have a crack at the amp board if I knew where to look.
Another option has occurred to me: since my system is active and each amp channel has its own gain setting, I could drive two 221s with external amps instead of my 242s' bass channel. Is the servo control essential? Might that work? I'm finding the 242s a little boxy without the 221...
I blew the other one a few days ago by knocking my cantilever against the edge of a record with the volume way too high. I would be willing to have a crack at the amp board if I knew where to look.
Another option has occurred to me: since my system is active and each amp channel has its own gain setting, I could drive two 221s with external amps instead of my 242s' bass channel. Is the servo control essential? Might that work? I'm finding the 242s a little boxy without the 221...