Peerless 12SLS... for a 3 way (small) monitor

AstroMick

Member
2016-01-30 3:46 am
Hi everyone :wave2:

Thinking of a project...a monitor for my small, but cozy study/computer room.
I like all kind of music...mostly old (like me) rock, some classical and jazz...

So, I have a pair of Peerless 830669 12"woofers for bass, and 6 Vifa's M13SG 16 ohm mids...with Vifa tweeters.

The aim is to have a small-ish box on my big desk, but still achieve high-ish spl in a 3 way... sick of flimzy-don't push me 2way's.

To make the Peerless 'punch' need a big box....however, could extend the lows by
1: series capacitor 400uF ----1200uF to make it a 3rd order HP
2: Linkwitz transform in the modified amplifier
Both would use a 25l to 40l closed box.
Not worry about amp clipping, or xmax limit.... I sit 2m away so spl is @ 96dB is good enough.

So, my question is... how would this system would sound? Anyone tried a simple cap-in woofer with optimized closed box volume to achieve lower -3dB? How is that sound like...in room? Or do the Ltransfer and make it adjustable to the room boundaries?

For the mids, I have 3/ch of the Vifas and want to do an open baffle like the
Acarian Alón suported by the small sealed box of the Peerless.

Sorry for the long post ....and the not perfect English/grammar ...still learning :blush:

Cheers,
Mick
 
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And now I see those fabolous Acarian Alón ...indeed what I see is the Phalanx/Poseidon model with 6 woofers...
The fact is that you call it small, which is quite the opposite.
Everything's relative...
My suggestion still stands: woofer on top, tweeter in the middle and the 3 mid-wf arranged in a triangle, below. It's in contradiction to the proposition on standing on the table, 'cos the mid frequencies will suffer from some surface reflection...but who cares! one 12" wf and 3X 6" mid-wf's !!!! Poor tweeter, so little and alone...
Some faceted baffle to incline the drivers would be well accepted, tweeter firing Horizontal and the woofer and the mid-wf's disposed on an virtual arc.
The mids...who knows- they'll benefit from low crossover frequency
 

AstroMick

Member
2016-01-30 3:46 am
Thanks guys,
CharlieLaub : hmmm...for music, don't like sat/sub system...for HT I had the Shiva BR tuned to 18Hz, hard to integrate to music...break glass for HT :)

What I try to archive is 'kick-drum' punch in a small-is box to do justice to Moby Dick by Led Zeppelin ... for vocal Dianna Krall , and Nora Jones's purr... or Beethoven's aggression..... + Liszt's finesse

If the open-back-mid not a good idea....how about just one of the Vifa in a Tractrix horn?
Spec say half space SPL is 84dB/16ohm ...in a horn this may be 90-94db/2.38V ???

Still, how would the Peerless 12" sound like in a small sealed box, with a Linkwitz transfer or a series cap?

Mick





http://www.diyaudio.com/forums/members/charlielaub.htmlhttp://www.diyaudio.com/forums/members/charlielaub.html
 
Thanks guys,
CharlieLaub : hmmm...for music, don't like sat/sub system...for HT I had the Shiva BR tuned to 18Hz, hard to integrate to music...break glass for HT :)
So you built a sub+sat system that didn't turn out to be all that and now you write off that entire class of loudspeaker? Alrighty then. A loudspeaker is more than some drivers and some (crossover) network put together. Careful design of the system is important. How did you accomplish that? I would first look for flaws in the execution before writing off all sub+sat systems.

Unfortunately, for OB mids, locating them on the desk and (I assume) near a wall will cause more problems than it (the OB loading) will solve. This is because peaks and nulls will form from the interaction of the direct and reflected (off off the surfaces) sound. In a properly implemented OB system (meaning properly designed and set up in the room) the combination of direct and reflected sounds is what increases that spaciousness of the soundstage, but only when the distances to rear and side walls is more than about 1.5m or 2m. When you "hear" (the brain receiving) delayed versions of the direct sound (delay coming from the longer pathlength of the sound reflected from boundaries) these distances the brain perceives these as enhanced "space". When the boundaries are closer the short(er) time delay results in the brain lumping the reflected sound and direct sound together, and the result is perceived as comb filtering (tonal changes). This is why a desktop open baffle is just not practical. But that doesn't seem to stop people from trying it!

Instead I would design an MTM type system with the lower woofer right at the desk to minimize reflections. The upper woofer is only brought in to augment the lower end and the longer wavelengths there will reduce comb filtering problems. Put the tweeter in the middle, carefully design a crossover, and then cross over below 150Hz to the subs.

What I try to archive is 'kick-drum' punch in a small-is box to do justice to Moby Dick by Led Zeppelin ... for vocal Dianna Krall , and Nora Jones's purr... or Beethoven's aggression..... + Liszt's finesse
This sounds very phenomenological. I would instead try to think in terms of smooth frequency response (on and off axis), transient response, room response, SPL output capability, and distortion. These can actually be measured/quantified, designed into the system, and properly implemented.

If the open-back-mid not a good idea....how about just one of the Vifa in a Tractrix horn?
Spec say half space SPL is 84dB/16ohm ...in a horn this may be 90-94db/2.38V ???
A tractrix horn... haha, that's a good one! How large is this desk, anyway? Where do you plan to put this large horn???

Still, how would the Peerless 12" sound like in a small sealed box, with a Linkwitz transfer or a series cap?
Frankly the Peerless SLS 12 needs quite a LARGE closed box to give you any kind of bass and flat passband. A quick look at the TS specs and/or some response modeling should make this quite evident. These are absolute the WRONG driver for a small sealed box. In the "right" box they will be quite nice, however, that box will be pretty large and that is why I suggested that you put it under your desk (or use it AS your desk!).

If you really want some nice bass in your chair with these SLS woofers (and only there) there is one possibility for OB bass that you might consider - nearfield listening. Even with literally no baffle, if you put your ear very close to a woofer you can hear the bass. So the idea is to put the woofers in an OB or open back cab RIGHT BEHIND YOUR HEAD or no more than a foot or so away from your ears. You are now in the nearfield and the perceived response is like an infinite (sealed) baffle enclosure. This would be very nice with these drivers, but you have to live with the physical setup (wife approval factor likely low) looming very close to you.
 
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