Flint Acoustics: "Lil Jokers & Arthur" indoor edition
- Thread starter Flint
- Start date
We've had a big change in the weather as Autumn blew in over a week ago. As such, the finish has been very slow to dry. Hopefully today I can put a shiny coat of Polyurethane on these enclosures.
I've done all that I can do until the finish is cured.
Running about a week behind my estimated timeline, which frustrated me.
I've done all that I can do until the finish is cured.
Running about a week behind my estimated timeline, which frustrated me.
Deerhunter
Well-Known Member
Looking sweet
My initial listening session was surprisingly good.
All done!
I have made loads of measurements... and here they are:
Impulse Response of the satellite speakers. Note the narrow width of the impulse, all aligned almost perfectly. This is a common benefit of using a good Coaxial driver where the tweeter is mounted inside the voice coil of the woofer.
Phase response (green line). Note how smooth this is with only a slight hiccup in the 2kHz range caused by the passive filter I used to smooth the midrange frequency response. This is a drawback of passive filters. But, otherwise the crossover range (5 - 8 kHz) is smooth as can be. YAY!!!
The overall frequency response of the satellites and subwoofer: The top end includes measurements made at 0, 15, 30 and 45 degrees (Black, Red, Purple, and Gray, respectively). The bottom end of the satellite is with the port open (black) or plugged (brown). The subwoofer curves are with the port plugged (brown) or open (blue).
The amp I am using with these speakers includes a tone control, so I tuned the passive crossover to make the tweeter naturally too bright, but then the when the tone control is set to the center position the satellite is flat (brown). Turn the tone control to the highest setting and you get the black curve and set to the lowest gets you the red curve. This allows for the listener to adjust the tone to their tastes, room acoustics, listening levels, and to compensate for bad recordings.
I have made loads of measurements... and here they are:
Impulse Response of the satellite speakers. Note the narrow width of the impulse, all aligned almost perfectly. This is a common benefit of using a good Coaxial driver where the tweeter is mounted inside the voice coil of the woofer.
Phase response (green line). Note how smooth this is with only a slight hiccup in the 2kHz range caused by the passive filter I used to smooth the midrange frequency response. This is a drawback of passive filters. But, otherwise the crossover range (5 - 8 kHz) is smooth as can be. YAY!!!
The overall frequency response of the satellites and subwoofer: The top end includes measurements made at 0, 15, 30 and 45 degrees (Black, Red, Purple, and Gray, respectively). The bottom end of the satellite is with the port open (black) or plugged (brown). The subwoofer curves are with the port plugged (brown) or open (blue).
The amp I am using with these speakers includes a tone control, so I tuned the passive crossover to make the tweeter naturally too bright, but then the when the tone control is set to the center position the satellite is flat (brown). Turn the tone control to the highest setting and you get the black curve and set to the lowest gets you the red curve. This allows for the listener to adjust the tone to their tastes, room acoustics, listening levels, and to compensate for bad recordings.
The normalized off axis polar plot. Note that the output changed very little through the midrange and when the tweeter takes over in the 7 - 8 khz range it expands again. Still great output over a wide area. These have a good power response (I may assemble a forward power response curve and post it).
Here's the same data in the polar response without normalizing - this reflects the actual frequency response of the system and not just how the output changes off axis.
Here's the THD plot with the volume adjusted for 90dB SPL at 1/2 Meter and the port plugged (in typical usage with the subwoofer the port will be plugged).
Here's the THD plot with the volume adjusted for 100dB SPL at 1/2 Meter and the port plugged (in typical usage with the subwoofer the port will be plugged).
I've had a few requests to show the backs of the satellites and the bottom of the assembled subwoofer, so...
The subwoofer baffle - Note the four bolts around the vent where the port plug can be mounted to seal the enclosure and get a less deep, but slightly tighter tonality.
Rear of the Satellite with the port plug installed. With these small enclosures the port plug simply slides in place and seals the port as the plastic ports I used slightly taper as you go into the enclosure. So, the part I cut off slips right into the outer flare end and seals really well. So, I merely filled the part I cut off and put a metal hook in it as a means to pull it out and it makes a perfect port plug.
Same speaker with the port plug removed. I made the satellites as a mirrored pair so the ports are always on the outside or the inside, which isn't critically important, but it make them look more refined. If I sold these commercially I'd either have to package them in pairs to ensure each customer got a "left" and "right" speaker, or I'd have to abandon the idea of a mirrored pair approach. Since these are hand-made on commission, these little things differentiate the speakers from mass market models.
The subwoofer baffle - Note the four bolts around the vent where the port plug can be mounted to seal the enclosure and get a less deep, but slightly tighter tonality.
Rear of the Satellite with the port plug installed. With these small enclosures the port plug simply slides in place and seals the port as the plastic ports I used slightly taper as you go into the enclosure. So, the part I cut off slips right into the outer flare end and seals really well. So, I merely filled the part I cut off and put a metal hook in it as a means to pull it out and it makes a perfect port plug.
Same speaker with the port plug removed. I made the satellites as a mirrored pair so the ports are always on the outside or the inside, which isn't critically important, but it make them look more refined. If I sold these commercially I'd either have to package them in pairs to ensure each customer got a "left" and "right" speaker, or I'd have to abandon the idea of a mirrored pair approach. Since these are hand-made on commission, these little things differentiate the speakers from mass market models.
