My Velodyne EQ Max 15 which I bought quite a few years back was giving a pop sound when turning on. Two days ago, it stopped working. I had two options. Give the board for repair or get a new board, both would take time and money. While I was trying to figure out what to do, (It's hard to get by without a sub for movies, after you have gotten used to it) I thought, since I had the Crown XLS 2502, why not just connect the woofer to the amp and try it out.
The amp plate has funny screws. Luckily, I had a set of screw drivers, one of which worked. Carefully unscrewed the back plate only to find an imposing looking board. I don't even know the difference between a capacitor and a resistor so you can imagine. There was a lot of padding inside the box, so gingerly put my hand into the box trying to find the wires coming out of the speakers. Was expecting cockroaches or worse to come crawling into my hand as this is a duel ported woofer with the ports under the speaker. Finally found the wires and tried to pry them loose from the board. Nope, couldn't. Took scissors to it. It was a strange looking wire. No strands. Just one piece of tough wire.
Taking the wire out of the box was a problem. Took them through the back plate leaving a gap and connected them to the crown. Played some songs. Damn, that worked !!! Was sounding ok too. Played the subwoofer frequency test sounds recently uploaded by @OM_2K19. The 20 Hz tone was making a lot of air come out of the gap between the plate and the wire and was creating vibrations and sounds too. Thought I had to live with it as I did not want to make any holes in the box and the back plate was looking too intimidating to try and get the wires out of the speaker switches.
A few hours passed, then another idea. Opened the plates, ran the wire out through one of the Ports !!! Was now able to nicely and tightly close the back plates. Tested with the 20 Hz tone again. This time, no vibrations, no unwanted noises. Maybe the Port did not like my passing a wire through it, but it did not complain at all.
The Velodyne had a 750 Watt RMS amp. I am now running it with a 440 W amp. Tried bridging but since I am not maxing out 440W, the Bridge did not make any difference. Since, I was using this amp for stereo too, I did not want to keep the bridge setting if it did not make a difference. Tried the Low pass filter at 80. This too did not make a difference as I was taking the sub out from the receiver to it was it was sending 80Hz and below only anyway to the amp.
One thing that I noticed now is that the woofer is moving quite a lot from earlier when it was running on its own amp. It goes deep enough for movies but for music, there is a new nice chest hitting punch that I did not notice earlier with it's own amp. Maybe I was not running it loud enough earlier. Maybe the original amp was doing some EQ that was making the woofer sound that way. I don't know.
Overall, am more than satisfied. I am still using the crown for stereo with the Tidal - Roon - Zen Dac - Tube pre - Crown chain as all the connectors are easy to change and it takes less than 15 seconds to do the same.
The amp plate has funny screws. Luckily, I had a set of screw drivers, one of which worked. Carefully unscrewed the back plate only to find an imposing looking board. I don't even know the difference between a capacitor and a resistor so you can imagine. There was a lot of padding inside the box, so gingerly put my hand into the box trying to find the wires coming out of the speakers. Was expecting cockroaches or worse to come crawling into my hand as this is a duel ported woofer with the ports under the speaker. Finally found the wires and tried to pry them loose from the board. Nope, couldn't. Took scissors to it. It was a strange looking wire. No strands. Just one piece of tough wire.
Taking the wire out of the box was a problem. Took them through the back plate leaving a gap and connected them to the crown. Played some songs. Damn, that worked !!! Was sounding ok too. Played the subwoofer frequency test sounds recently uploaded by @OM_2K19. The 20 Hz tone was making a lot of air come out of the gap between the plate and the wire and was creating vibrations and sounds too. Thought I had to live with it as I did not want to make any holes in the box and the back plate was looking too intimidating to try and get the wires out of the speaker switches.
A few hours passed, then another idea. Opened the plates, ran the wire out through one of the Ports !!! Was now able to nicely and tightly close the back plates. Tested with the 20 Hz tone again. This time, no vibrations, no unwanted noises. Maybe the Port did not like my passing a wire through it, but it did not complain at all.
The Velodyne had a 750 Watt RMS amp. I am now running it with a 440 W amp. Tried bridging but since I am not maxing out 440W, the Bridge did not make any difference. Since, I was using this amp for stereo too, I did not want to keep the bridge setting if it did not make a difference. Tried the Low pass filter at 80. This too did not make a difference as I was taking the sub out from the receiver to it was it was sending 80Hz and below only anyway to the amp.
One thing that I noticed now is that the woofer is moving quite a lot from earlier when it was running on its own amp. It goes deep enough for movies but for music, there is a new nice chest hitting punch that I did not notice earlier with it's own amp. Maybe I was not running it loud enough earlier. Maybe the original amp was doing some EQ that was making the woofer sound that way. I don't know.
Overall, am more than satisfied. I am still using the crown for stereo with the Tidal - Roon - Zen Dac - Tube pre - Crown chain as all the connectors are easy to change and it takes less than 15 seconds to do the same.
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