Hi guys,
Yes, I measured 6.2ohms, but that was with a (cheap, although good-branded) handheld meter. I wouldn't be surprised if it were off by 10 or 20% in this very low range (top of scale is 200ohms, I think).
Anyway, I have just purchased that #300-792 from PartsExpress. Can't wait to have it home and put it to work.
VMat
Yes, I measured 6.2ohms, but that was with a (cheap, although good-branded) handheld meter. I wouldn't be surprised if it were off by 10 or 20% in this very low range (top of scale is 200ohms, I think).
Anyway, I have just purchased that #300-792 from PartsExpress. Can't wait to have it home and put it to work.
VMat
Okay, I found a replacement driver which was 8ohm, 300W, and a 50 ounce, ported magnet. Some cheapo no-name brand called "Rock Sound" that I paid only $25 cdn for
Anyhow, I installed it and it worked fine for a little bit. Then it started doing the same thing as my original sub. What happens is pretty simple. The speaker volume drops to almost nothing at mostly lower volumes. At maximum volume it works for about 5-10 minutes after I push the front or back rim of the cone with my hand.
Like WTF could be causing that? Strangly enough this speaker works slightly better than the last. I'm pretty sure it's not the speaker but something to do with the amp. Perhaps pushing against the cone exerts physical resistance which changes the characteristics of the load. I dunno, it has to be the amp. Unless the it could be the driver impedance in combination with the amp (which has been previously repaired)
Anyone know what could be causing this? It's getting really tiresome going pushing the speaker in every 5-10 minutes
Anyhow, I installed it and it worked fine for a little bit. Then it started doing the same thing as my original sub. What happens is pretty simple. The speaker volume drops to almost nothing at mostly lower volumes. At maximum volume it works for about 5-10 minutes after I push the front or back rim of the cone with my hand.
Like WTF could be causing that? Strangly enough this speaker works slightly better than the last. I'm pretty sure it's not the speaker but something to do with the amp. Perhaps pushing against the cone exerts physical resistance which changes the characteristics of the load. I dunno, it has to be the amp. Unless the it could be the driver impedance in combination with the amp (which has been previously repaired)
Anyone know what could be causing this? It's getting really tiresome going pushing the speaker in every 5-10 minutes
Been reading this entire thread for about 2 hours now and I'm amazed by all your efforts to fix this problem with this amp. I also commend pat for all that work, even though at the end of it all it was scrapped.
I have a PB10 and a week ago I noticed that it was not on. So I opened it up and saw that the 3AG fuse was blown. Went got a pack of new fuses. Put the new fuse in and as soon as I turned it on it blew. So I took it to a friend that is an audio equipment engineer for a local radio station. Checked it out and said that it was the S53AMI module.
Now i've read all your posts and most of the symptoms you guy's are getting are the Hummming and the poping but nothing about a blown fuse. My question is could a faulty module be the cause of the amp to keep blowing the fuse? Or could it be something else. Even worse is that I have two of these subs. One is still functional. I was thinking of taking the module of the good sub and trying it out on the busted amp to confirm that this is what is causing it to blow the fuse.
Let me know your thoughts.
I have a PB10 and a week ago I noticed that it was not on. So I opened it up and saw that the 3AG fuse was blown. Went got a pack of new fuses. Put the new fuse in and as soon as I turned it on it blew. So I took it to a friend that is an audio equipment engineer for a local radio station. Checked it out and said that it was the S53AMI module.
Now i've read all your posts and most of the symptoms you guy's are getting are the Hummming and the poping but nothing about a blown fuse. My question is could a faulty module be the cause of the amp to keep blowing the fuse? Or could it be something else. Even worse is that I have two of these subs. One is still functional. I was thinking of taking the module of the good sub and trying it out on the busted amp to confirm that this is what is causing it to blow the fuse.
Let me know your thoughts.
Hi,
They had a number of problems across all versions it seems, hard to say which of the many could be affecting you.
A faulty module should blow the fuse I'd think. Can't say with any degree of certainty that plugging in a working module won't destroy that working module so for that reason I'd advise against it.
Enjoy the one you have left while it lasts.
They had a number of problems across all versions it seems, hard to say which of the many could be affecting you.
A faulty module should blow the fuse I'd think. Can't say with any degree of certainty that plugging in a working module won't destroy that working module so for that reason I'd advise against it.
Enjoy the one you have left while it lasts.
I *think* this amp will work: http://www.apexjr.com/CVT200S.htm
I was considering buying one to replace a dead pb12 amp, at one point. You would have to enlarge the original amp cutout in order for it to fit, though. Haven't been able to find any other amps that are larger in both dimensions then the original other than the cerwin vega amp.
I was considering buying one to replace a dead pb12 amp, at one point. You would have to enlarge the original amp cutout in order for it to fit, though. Haven't been able to find any other amps that are larger in both dimensions then the original other than the cerwin vega amp.
For PB-10
I put my old PB-10 and new #300-792 (from PartsExpress) together 3 days ago. So far, so good. I haven´t pushed it really hard, but it sounded good to me at the levels I used it. I watched "Matrix" (DD) and "Minority Report" (DTS), and some random tracks from Peter Gabriel's "Growing Up" (DTS) and Sting's "All This Time" (DD). No complaints, except that sometimes I think the threshold for turning on in "Auto" mode is a bit too high - meaning that I have to either go to the amp and manually change the mode to "On" and back to "Auto", or turn the receiver volume up until the sub turns on, and then back down. Maybe I'll just leave it on all the time.
I have also managed to connect the led's in the sub to the amp. If anyone is interested, open the amp, follow the track from the led until you reach a resistor. At the other end of the resistor, there is another track that goes to the flat cable. The voltage in this track is approximately +12V for green and -12V for red. I brought this signal to a DB-9 connector at the rear panel, with an 820-ohm resistor in series. I think 1k or 1k2 would be even better (the led's seem a bit too bright), maybe I'll replace it sometime soon.
DISCLAIMER: (obviously) don't blame me if you do that and your amp or sub blows up. I can give you no warranty.
The down side is that this amp will not fit in the PB-10 back without removing the port, which I didn't want to do. So I decided to build an external housing for the amp, and cover the original cutout with wood.
A couple of pictures are attached.
Good luck!
I put my old PB-10 and new #300-792 (from PartsExpress) together 3 days ago. So far, so good. I haven´t pushed it really hard, but it sounded good to me at the levels I used it. I watched "Matrix" (DD) and "Minority Report" (DTS), and some random tracks from Peter Gabriel's "Growing Up" (DTS) and Sting's "All This Time" (DD). No complaints, except that sometimes I think the threshold for turning on in "Auto" mode is a bit too high - meaning that I have to either go to the amp and manually change the mode to "On" and back to "Auto", or turn the receiver volume up until the sub turns on, and then back down. Maybe I'll just leave it on all the time.
I have also managed to connect the led's in the sub to the amp. If anyone is interested, open the amp, follow the track from the led until you reach a resistor. At the other end of the resistor, there is another track that goes to the flat cable. The voltage in this track is approximately +12V for green and -12V for red. I brought this signal to a DB-9 connector at the rear panel, with an 820-ohm resistor in series. I think 1k or 1k2 would be even better (the led's seem a bit too bright), maybe I'll replace it sometime soon.
DISCLAIMER: (obviously) don't blame me if you do that and your amp or sub blows up. I can give you no warranty.
The down side is that this amp will not fit in the PB-10 back without removing the port, which I didn't want to do. So I decided to build an external housing for the amp, and cover the original cutout with wood.
A couple of pictures are attached.
Good luck!
Bomp!
What do you guys think about using 40106 instead of the original 74ACT14 ? Then it could run on 12 volts instead of 6 volts and it would be less prone to failure as 40106 can take 18 volts of abuse before it blows, this would also turn the fets on fully making less heat.
Here is an idea of mine, that i may try today. Rails would be 35-40 volts.
What do you guys think about using 40106 instead of the original 74ACT14 ? Then it could run on 12 volts instead of 6 volts and it would be less prone to failure as 40106 can take 18 volts of abuse before it blows, this would also turn the fets on fully making less heat.
Here is an idea of mine, that i may try today. Rails would be 35-40 volts.
Attachments
classd4sure said:
Thats the major problem, the fuse will not blow if the amp is faulty, then it fry the speaker. Thats what mine did at least. yes the fuse was of the correct rating.
and the funniest thing is that there is some sort of current sens on the output to prevent this...it just stop the amp to oscillate...
they were assuming that the amp was ok if the protection engaged !!!!
Pat allen
Still pounding!
It's been a while since I posted to this forum regarding the lovely PB12's. As you may recall I helped to demystify the original s64ami module. I have 3 of these subs, and one needed that module replaced, the other two subs only needed capacitors. I had all 3 going! Well, it's been over a year now, and the 2 subs that needed caps are now dead again, and I'm pretty convinced that one of them will need the s64ami module redone this time. The original mods I made with the 3rd sub's s64ami module is still rockin' and pounding as hard as ever! YAY! I've even put it through the torture of running for a solid month, with occasional very high input signal! Oh yeah, she got hot, but she never faultered!
GL to ya'll
Jeremy
It's been a while since I posted to this forum regarding the lovely PB12's. As you may recall I helped to demystify the original s64ami module. I have 3 of these subs, and one needed that module replaced, the other two subs only needed capacitors. I had all 3 going! Well, it's been over a year now, and the 2 subs that needed caps are now dead again, and I'm pretty convinced that one of them will need the s64ami module redone this time. The original mods I made with the 3rd sub's s64ami module is still rockin' and pounding as hard as ever! YAY! I've even put it through the torture of running for a solid month, with occasional very high input signal! Oh yeah, she got hot, but she never faultered!
GL to ya'll
Jeremy
Hi all,
I have a sub with a S54AMI module, however it is not a JBL it is a Mission 70ASA. The symptoms are that the fuse blows moments after I plug it in. There aren't any obvious signs of fried components on the board.
Should I try testing the capacitors or is it most likely the module that is toast? I will probably put together a chip amp or something to replace it if I cant get it working. Any idea on how to salvage the crossover component?
I have a sub with a S54AMI module, however it is not a JBL it is a Mission 70ASA. The symptoms are that the fuse blows moments after I plug it in. There aren't any obvious signs of fried components on the board.
Should I try testing the capacitors or is it most likely the module that is toast? I will probably put together a chip amp or something to replace it if I cant get it working. Any idea on how to salvage the crossover component?
