I got the coils swapped properly. Here's what I got.
Initially the zobel didn't seem to be doing much until I realized I had used the wrong impedance for the tweeter when calculating the high pass crossover.
The new cap and coil values needed to be 3.24uF and .61mH. I added a .47uF cap in parallel with the .27uF cap which with the actual value of the cap which is .49uF the combined value is within a 5% tolerance of 3.24uF
Here's the updated schematic.
Here's a photo of the speaker.
Decided to move the volume control of the amp to the front of the speaker as given the pot's shaft was so short I had to rig up a knob and I didn't like having to reach around the rear to adjust the volume.
The original pot is a dual 10k audio taper and I happened to have an Alps dual 10k audio taper pot. Based on what tracing of the board I did, it looks like the volume control is after an OP-AMP meaning the impedance will be lower so I could possibly get away with some three wire twisted wire (done like a hair braid is) for the right and left channel volume control wiring.
Once I removed the stock pot I used an ohmmeter to determine what terminals were what.
The amp's power connector doesn't have a nut on it to hold it to the front panel. Pretty sure I have something that will fit somewhere.
Initially the zobel didn't seem to be doing much until I realized I had used the wrong impedance for the tweeter when calculating the high pass crossover.
The new cap and coil values needed to be 3.24uF and .61mH. I added a .47uF cap in parallel with the .27uF cap which with the actual value of the cap which is .49uF the combined value is within a 5% tolerance of 3.24uF
Here's the updated schematic.
Here's a photo of the speaker.
Decided to move the volume control of the amp to the front of the speaker as given the pot's shaft was so short I had to rig up a knob and I didn't like having to reach around the rear to adjust the volume.
The original pot is a dual 10k audio taper and I happened to have an Alps dual 10k audio taper pot. Based on what tracing of the board I did, it looks like the volume control is after an OP-AMP meaning the impedance will be lower so I could possibly get away with some three wire twisted wire (done like a hair braid is) for the right and left channel volume control wiring.
Once I removed the stock pot I used an ohmmeter to determine what terminals were what.
The amp's power connector doesn't have a nut on it to hold it to the front panel. Pretty sure I have something that will fit somewhere.
Here's a picture of the back I added to the speaker.
I went ahead and added a 1/4" jack for the other speaker output. That way if I happen to find another identical woofer, I can have a pair of stereo speakers or with a female RCA to two male RCA splitter cable I can have two mono speakers.
The hole is so I can carry the speaker.
I don't like the amp being secured by only screws on the bottom so what I may do is find a piece of wood to cut and go between both sides of the speaker and secure it with two L brackets and glue. I can then use the two top holes in the amp to secure it. Before I do that though I need to make sure I'll be able to remove the woofer should I ever need to replace it.
Also I don't like the auto off feature of the amp when there's no signal or a low signal. I'll need to find a way to disable that feature while keeping the speaker protection feature. The amp does have a 12 volt trigger/video in jack so perhaps I can connect +12V to that jack permanently so the amp stays on. I figure a 12 volt zener in parallel with that input and a series resistor between B+ and the zener would work fine and could be installed on the board itself. For the subwoofer output should I ever want to use it, I could cut the trace of the Video/+12V trigger output and solder a wire from the + sub output to that jack. That way I can plug in a sub without needing to mount a jack.
I achieved my goal which was to have a speaker that sounds decent enough for when I just want music at work. The subwoofer out is a low pass of 85Hz at 12dB/octave. The selectable high pass is flat, 30Hz 12dB/octave & 100Hz 12 dB/octave. Not sure how they ever expected a sub to integrate properly given the high pass and low pass are two different frequencies.
I went ahead and added a 1/4" jack for the other speaker output. That way if I happen to find another identical woofer, I can have a pair of stereo speakers or with a female RCA to two male RCA splitter cable I can have two mono speakers.
The hole is so I can carry the speaker.
I don't like the amp being secured by only screws on the bottom so what I may do is find a piece of wood to cut and go between both sides of the speaker and secure it with two L brackets and glue. I can then use the two top holes in the amp to secure it. Before I do that though I need to make sure I'll be able to remove the woofer should I ever need to replace it.
Also I don't like the auto off feature of the amp when there's no signal or a low signal. I'll need to find a way to disable that feature while keeping the speaker protection feature. The amp does have a 12 volt trigger/video in jack so perhaps I can connect +12V to that jack permanently so the amp stays on. I figure a 12 volt zener in parallel with that input and a series resistor between B+ and the zener would work fine and could be installed on the board itself. For the subwoofer output should I ever want to use it, I could cut the trace of the Video/+12V trigger output and solder a wire from the + sub output to that jack. That way I can plug in a sub without needing to mount a jack.
I achieved my goal which was to have a speaker that sounds decent enough for when I just want music at work. The subwoofer out is a low pass of 85Hz at 12dB/octave. The selectable high pass is flat, 30Hz 12dB/octave & 100Hz 12 dB/octave. Not sure how they ever expected a sub to integrate properly given the high pass and low pass are two different frequencies.
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Concerning this speaker is there any point in making this an open baffle design?
I could either remove the baffle from the cabinet if it is large enough or I can use some wood and build a new baffle then add a base for the amp and crossover to be mounted on.
Of course I can just take the speaker home, remove the baffle from the cabinet and see how it sounds compared to the baffle being attached to the cabinet.
Using the original baffle would be nice due to the grill cloth that will protect the woofer, but if a new baffle is needed I can make one. I'm working on another open baffle speaker and will have a 15" round cutout of 3/4" thick wood. I can make the bottom of that square perhaps and use it for the new baffle with the tweeter mounted right above the woofer.
I could always leave it circular and figure a way to attach it to a base unless a circular baffle is a no-go far as sound is concerned.
I could either remove the baffle from the cabinet if it is large enough or I can use some wood and build a new baffle then add a base for the amp and crossover to be mounted on.
Of course I can just take the speaker home, remove the baffle from the cabinet and see how it sounds compared to the baffle being attached to the cabinet.
Using the original baffle would be nice due to the grill cloth that will protect the woofer, but if a new baffle is needed I can make one. I'm working on another open baffle speaker and will have a 15" round cutout of 3/4" thick wood. I can make the bottom of that square perhaps and use it for the new baffle with the tweeter mounted right above the woofer.
I could always leave it circular and figure a way to attach it to a base unless a circular baffle is a no-go far as sound is concerned.
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Well we had what Bob Ross would say was a happy accident.
Grabbed the paint as I was in a hurry and only saw the cap and the word satin. So I thought it was satin black. Instead I was greeted with this color.
Here's how it looks.
Grabbed the paint as I was in a hurry and only saw the cap and the word satin. So I thought it was satin black. Instead I was greeted with this color.
Here's how it looks.
It depends on how much space you have, open baffles require lots of space from the walls.
Baffle shape and size are constantly debated on the forum. The two trends are to; have whole sheets of 4x8 plywood in your living room, and the other extreme is to simply hang the drivers from piano wire. Personally I prefer sealed boxes in a teardrop shape in my small listening room. YMMV.
I've got the speaker pretty much finished. Just need to secure the amp and figure something to cover the crossover with.
I'm dumbfounded as to how good this speaker sounds. I know I'd need a sub if I wanted bass response to 20Hz, however where I'm using the speaker that is not a requirement and the speaker as is seems to sound like it plays low enough at least for the radio station I stream at work which puts a feed from an AM stereo tuner online so that people online can hear how good AM stereo really sounds.
I'm dumbfounded as to how good this speaker sounds. I know I'd need a sub if I wanted bass response to 20Hz, however where I'm using the speaker that is not a requirement and the speaker as is seems to sound like it plays low enough at least for the radio station I stream at work which puts a feed from an AM stereo tuner online so that people online can hear how good AM stereo really sounds.
Cover up the crossover? But, they look so nice. 👍👍
For a shop speaker I don't usually put in that much engineering, I usually guess and then go with it for a while and keep improving it until I get some extra speakers from another project and then it starts over. My shop speakers are a continuum.
For a shop speaker I don't usually put in that much engineering, I usually guess and then go with it for a while and keep improving it until I get some extra speakers from another project and then it starts over. My shop speakers are a continuum.
Covering the crossover is because it will be used where I work and I don't want anything to be said about exposed terminals.
Decided to use some cardboard to cover the crossover and the rear of the volume control. That way all exposed terminals are covered and it also somewhat protects the crossover and control given both are out in the open. A little paint and some glue is all I needed. To make it easier to service the crossover the rear of the cardboard cover is secured with double sided tape while for the front right and rear right past where the cable exits I used a dab of gorilla glue. Once the glue sets I may spray some paint in a small cap and pour it over the glue.
I may get some of those stick on feet to put on the bottom.
If I can find another identical woofer (that one is discontinued), I could build a second speaker and have a set of speakers given the amp is stereo. The speaker goes quite loud too and sounds very good doing it.
I may get some of those stick on feet to put on the bottom.
If I can find another identical woofer (that one is discontinued), I could build a second speaker and have a set of speakers given the amp is stereo. The speaker goes quite loud too and sounds very good doing it.