3way Discovery or...

Hi!

Wanna begin with new project of 3way speakers. Classical scheme - 10" + 5" + tweeter. Preffering sealed box. Budget about 350-400 euro on speakers set. Basic idea on discovery series 26W4534 + 15M4624 + some tweeter suitable. As alternative 3way on Seas Prestige. Say H1411 + MCA15RCY + some tweeter.

Need your advices and suggestions about best combinations in that price range.
 
Both the SS and Seas options would work, even if the woofers are more for a ported box but a sealed option is viable. Also the SBA suggestion is doable (I think the woofer is the SB29 as a SB26 doesn't seem to exist), at a higher price. And there is the problem: if the budget is 350/400 Euro for both speakers, you won't be able to achieve that. The cheaper option is SS, with a minimum of 180 Euro on drivers for a single speaker, and you have to add crossover components, wood, finishing etc.

Ralf
 
Well i've made my choice. SB23NRX + MR16P-4 + SB29RDC. Hope it's a good set of speakers 🙂

Good combination of drivers. It is smart budgeting to buy one Satori grade midrange and standard SB_acoustics woofer and tweeter. A single 8" SB23NRX45-8 ported woofer needs near-wall placement to match the 92db@2.83V sensitivity of the 4-ohm MR16P-4 midrange. If you want the BOOM-BOOM-BOOM you should consider two 8" or one 12" . The Sd increase between one 8" and one 10" is not large enough to provide significant SPL gain. There is a large selection of great 12" woofers. One $75 Dayton 12" DS315-8 woofer has -F3=36Hz in a sealed 2.3cuft volume. Zaph used one sealed 12" SB34NRX34-6.

==== Sd ====
18" 1220 cm2
15" 855 cm2
12" 530 cm2
10" 345 cm2
8" 225 cm2

What are your cabinet ideas?
 

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If you want a truly great compact driver (and not so compact enclosure) for sealed loading, spend the extra cash on a Scanspeak 25W/8565-00. If ported, dual SB23 in push push or a single SB29 in about 60l should be sufficient. The SB23 is also a good candidate for a practical MLTL and can produce good results in it.
 
I wanted sealed box at first. May be ss 26w4534g00 will be a better solution in pair to mr16?

The 10" Scan Speak 26W4534 woofer does model better in a sealed box alignment than the 8" SB23NRX35. The 26W4534 has Re=3.8ohms amplifier loading, and will favor iron core inductors with low resistance wiring. The aluminum cone on the 26W4534 show breakup above 2kHz which deserves some crossover consideration.

It is challenging to find a modest size woofer which can match the efficiency of the MR16P-4 midrange. Wall bass gain options from room placement are now part of the design.
 
The MR16P-4 has an underhung motor construction with Xmax of 3.1mm --- a true midrange --- not a midbass. A crossover frequency around 180Hz, near the baffle step frequency, seems like a good starting simulation. Simulating the baffle effects will also help set the woofer crossover.
 
The WinIsd sim uses bright green for the MR16P sealed box midrange, and illustrates the SPL differences between the discussed woofers. You can see the modest benefit from the 10" Scan Speak 26W4534 vs. the 8" SB23NRX35.
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This quick baffle + room effects simulation illustrates how cabinet baffle shape and area affects the baffle step, and hence crossover frequency selection plus crossover circuits. The sim also crudely illustrates placement and room effects which might help you select a woofer, and select final sealed or ported tuning.

A 11" - 12" wide cabinet starts ~ 300Hz baffle step.
A 16" wide cabinet starts ~ 200Hz baffle step.
The 30" wide cabinet of the Altec 19 starts baffle step ~ 100Hz.
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The example crossover assumes no room gain with one 8" sealed SB23NRX35 woofer, and illustrates the fast bass roll off.
With a single small area woofer, the room becomes part of the crossover design.
 

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Thanks. I've bought SB23NRX, MR16P-4 and SB26ADC as a result. I've changed my mind about SB29RDC 'cause i had Vifa XT25 ringradiator some time ago and didn't like it at all. Plus some negative feedbacks. Plus i just wanted to try metal dome tweeters always 🙂.

I'm planning to take Troels 3-Way Classic box for basis if TS woofer parameters will be close to what Troels measured. All in all i need real SB23NRX TS parameters for decision. That's a point.
 
I think with single SB23NRX vented box is most efficient option.
Despite the 980Hz resonance, I like the SMOOTH SB26STCN using a BW3 1850Hz crossover with the 92db MR16P-4. The 72mm front baffle allows a smaller C-to-C with a 6" midbass. Attached crossover illustrates typical port gain for the 8" SB23NRX45 with 24" from wall placement, plus SMOOTH SB26STCN.

Cabinet...consider a floor standing extension to Troels Illuminator Monitor box.
-Beveled top edges for diffraction control.
-Flat front baffle typically favors BW3 or LR4 crossovers.

If you can see dead people and hear port noises, maybe a floor port will control the deamons.
A few simple edge rounds add style.
 

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