I'm a long time reader of avforums.co.za, but never posted. I thought people might be interested in this simple Christmas project.
I've built various systems over the years ... an MTM system for my lounge my current favorite. But I wanted a good sound system for my computer desk ... I spend 8 hours a day at my desk, so figured it warranted some attention. I also wanted to experiment, and so after lots of thought experiments, I went for an open baffle mid-tweeter with a ripole bass as a quick Christmas project.
Drivers:
Hi-Vi B3S 3" wide range, after reading about it on http://www.zaphaudio.com/audio-speaker18.html
A pair of old 10" Audio Concepts AC10 drivers I salvaged from a prior system (Fs 24Hz Vas 3.92 Qts 0.38)
Amplifier: I purchased the unassembled 40W Audio Bi-Amplifier w/ Linkwitz-Riley Crossover from Xkitz Electronics https://www.xkitz.com/collections/active-crossovers-and-bi-amplifiers-1/products/audio-bi-amplifier-40w-w-linkwitz-riley-crossover-xamp-m2 - it was slow shipping ... 3 months!!! Assembly was easy. And I selected the active crossover at 150Hz
https://imgur.com/aoUbLuV
For the B3S, I went with an open baffle approach, placing the B3S speakers in a slim panel on either side of my 24" computer screen, making the computer screen effectively part of the baffle. Is that legitimate? I have no idea, but I tried it. The B3S use a filter as strongly recommended by Zaph (see zaph audio link above), where he notes "a 5 component filter, and I feel it's required for this design. Without the filter, the mids will sound shouty and forward due to a lack of baffle step compensation, and the 8kHz breakup node will be audible. This is true of any full range driver - BSC and breakup are serious issues that need to be dealt with."
Modeling the layout with Edge Baffle designer, I get a theoretical response
https://imgur.com/kr47PQB
For the Sub I chose a ripole design, I've been attracted to these for a long time. The box was constructed out of MDF, and was an easy build.
https://imgur.com/iIgjAmF
Overall a low risk experiment that was not meticulously designed, but rather a "Hey, when the Christmas break comes, what can I do quickly to try something fun?"
Setup of the bass / treble on the XKitz amp was by ear, although I will do a more formal calibration at some point.
How does it sound? Well, my only two comparisons are my lounge system, my headphones, and the prior computer sound system (a moderately expensive Sony system).
Comments:
The bass is the best I've ever heard. Seriously! One might be tempted to say a little dry - but maybe that is in comparison to the more familiar boominess of small subs that I've experienced. But you can hear the distinctiveness in the bass end so well. I don't quite have the words to describe it ... "tight" just doesn't capture it. My goto reference music is Dire Straits "Brothers in Arms" and "Communique", and the clarity of the distinctive sounds in the bass lines and the percussion is simply superb. No mud!
For the mids and highs, very pleasing. Certainly far better than any desk system I've heard. The sweet spot is broad, I can move comfortably across my screen without upsetting the sound stage. Closing my eyes and the spread of instruments is good, better than my lounge / home theater system.
Was it worth it?
From an economic sense, yes. The B3S are cheap. The subs drivers were salvaged, but are good drivers. The amp was a kit build, about 3 hours assembly, and at $42 each were the most expensive part of the system - but that got me a bi-amped system with active crossover.
From a sound perspective, I could not be more pleased. I am as satisfied with the sound as with my headphones.
I am sorely tempted to build ripoles for my living room!
I've built various systems over the years ... an MTM system for my lounge my current favorite. But I wanted a good sound system for my computer desk ... I spend 8 hours a day at my desk, so figured it warranted some attention. I also wanted to experiment, and so after lots of thought experiments, I went for an open baffle mid-tweeter with a ripole bass as a quick Christmas project.
Drivers:
Hi-Vi B3S 3" wide range, after reading about it on http://www.zaphaudio.com/audio-speaker18.html
A pair of old 10" Audio Concepts AC10 drivers I salvaged from a prior system (Fs 24Hz Vas 3.92 Qts 0.38)
Amplifier: I purchased the unassembled 40W Audio Bi-Amplifier w/ Linkwitz-Riley Crossover from Xkitz Electronics https://www.xkitz.com/collections/active-crossovers-and-bi-amplifiers-1/products/audio-bi-amplifier-40w-w-linkwitz-riley-crossover-xamp-m2 - it was slow shipping ... 3 months!!! Assembly was easy. And I selected the active crossover at 150Hz
https://imgur.com/aoUbLuV
For the B3S, I went with an open baffle approach, placing the B3S speakers in a slim panel on either side of my 24" computer screen, making the computer screen effectively part of the baffle. Is that legitimate? I have no idea, but I tried it. The B3S use a filter as strongly recommended by Zaph (see zaph audio link above), where he notes "a 5 component filter, and I feel it's required for this design. Without the filter, the mids will sound shouty and forward due to a lack of baffle step compensation, and the 8kHz breakup node will be audible. This is true of any full range driver - BSC and breakup are serious issues that need to be dealt with."
Modeling the layout with Edge Baffle designer, I get a theoretical response
https://imgur.com/kr47PQB
For the Sub I chose a ripole design, I've been attracted to these for a long time. The box was constructed out of MDF, and was an easy build.
https://imgur.com/iIgjAmF
Overall a low risk experiment that was not meticulously designed, but rather a "Hey, when the Christmas break comes, what can I do quickly to try something fun?"
Setup of the bass / treble on the XKitz amp was by ear, although I will do a more formal calibration at some point.
How does it sound? Well, my only two comparisons are my lounge system, my headphones, and the prior computer sound system (a moderately expensive Sony system).
Comments:
The bass is the best I've ever heard. Seriously! One might be tempted to say a little dry - but maybe that is in comparison to the more familiar boominess of small subs that I've experienced. But you can hear the distinctiveness in the bass end so well. I don't quite have the words to describe it ... "tight" just doesn't capture it. My goto reference music is Dire Straits "Brothers in Arms" and "Communique", and the clarity of the distinctive sounds in the bass lines and the percussion is simply superb. No mud!
For the mids and highs, very pleasing. Certainly far better than any desk system I've heard. The sweet spot is broad, I can move comfortably across my screen without upsetting the sound stage. Closing my eyes and the spread of instruments is good, better than my lounge / home theater system.
Was it worth it?
From an economic sense, yes. The B3S are cheap. The subs drivers were salvaged, but are good drivers. The amp was a kit build, about 3 hours assembly, and at $42 each were the most expensive part of the system - but that got me a bi-amped system with active crossover.
From a sound perspective, I could not be more pleased. I am as satisfied with the sound as with my headphones.
I am sorely tempted to build ripoles for my living room!
