Office Project: Monitors and Subwoofer

[trevordj]

In addition to working on my home theater and learning passive crossover design I have been building some speakers for my new business. I have had an original Continuum kit from Meniscus for the last 5 years waiting to be built. I have built the cabinets for these boxes at least 5 times, they just never turned out the way I wanted.

Well, when Jeff Bagby passed away earlier this year it motivated me to finally complete these speakers. I wanted them to be something special.




I also designed a subwoofer to go with these, it is called The Skausmas sub. Skausmas, in Lithuanian, means pain. I am opening a pain clinic in two weeks where these will live so it fit.



Each subwoofer cabinet had a Scanspeak Discovery 12” sub and a pair of matching passive radiators. I’ll post the technical stuff from my computer later. Each sub is powered by a SpeakerPower SP1-700 plate amp housed in its own sealed sub enclosure within the box.

All the speakers are finished in House of Kolor Jet Black with KC21 flat clear. The baffles are chamfered around the edge and are finished in a beautiful copper veneer and finished with House of Kolor USC-01 show clear. I modified the Continuum design to not have a removable front baffle, the woofer reverse mounts into blind threaded inserts through the removable rear panel. The removable rear panel is finished in piano gloss black using House of Kolor Jet Black and USC-01 show clear. I also designed and built integrated stands for them with a speakon connection at the bottom of the stands. I ran out of threaded inserts so a few are missing from the rear panel right now.

The speakers are powered by a Marantz MM7025 amplifier. The preamp is a MiniDSP SHD with integrated DiracLive. The input device is a SMSL SU-9 DAC. I built a custom remote box that powers everything with a single button push.


-Trevor

[trevordj]

I have a thing for building custom electronics boxes to meet my particular case use needs. In this case I wanted a box that could turn on both the MiniDSP SHD and the SMSL SU-9, neither of which have a trigger in or out. I also needed a way to trigger my plate amps and the Marantz amplifier. Here is what I came up with:



Under the hood it is very simple, there is a switch mode power supply and a relay. I attached them to the case bottom with some weld nuts acting as standoffs (weld nuts are way cheaper than standoffs and do the same thing in this case) epoxied to the case.



There is a powercon inlet and three powercon outlets, two are switched with the relay the other is always hot. There are two switchcraft mono jacks providing 1/8” standard switch out for remote turn on a as well.



Lastly there is a switch with a blue ring lit LED. The switch has pretty low power handling so it switches the 12v 1.25a coming from the power supply. The downside is that this means the power supply is running all the time if the unit is plugged in. This is very similar to many electronics, however, and I could simply wire in a rear switch to turn off the mains power supply if I wanted to, but I don’t find it necessary. I could simply twist off the powercon inlet if I wanted it completely off.

I wired a 470 ohm resistor in series with the ring LED on the switch.



If anyone needs any additional details on the exact materials I purchased for this let me know.

vimeo.com/479696932



-Trevor

[Timster]

Wow. Really nice work. I bet they sound as good as they look too. Awesome work

[daveczski65]

Beautiful craftsmanship..hope they sound as great as they look

[housetech]

Very nice.
They are much too pretty for grills.
Is there a reason the mids were not recessed surface mounted? 
 
Congrats.

[trevordj]

Nov 16, 2020 17:54:24 GMT -5 housetech said:

Very nice.
They are much too pretty for grills.
Is there a reason the mids were not recessed surface mounted? 
 
Congrats.

I’m not sure I’m exactly understanding, do you mean recessed and mounted on the front surface?

The kit came with all the crossover supplies and drivers along with a detailed plan how they were to be built. Changing the mounting would change the z axis offset and the crossover would need to be reworked.