Help for 3 or 4 way loudspeaker

Based in my actual 2 way I want to add other box with 2 woofers in parallel for a 3 way or one big sub-woofer for a 3 way or one woofer & one sub-woofer for a 4 way, I'm starting from zero: I don't have cabinets, filters, drivers, etc. so all suggestions will welcome.
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Based in my actual 2 way I want to add other box with 2 woofers in parallel for a 3 way or one big sub-woofer for a 3 way or one woofer & one sub-woofer for a 4 way, I'm starting from zero: I don't have cabinets, filters, drivers, etc. so all suggestions will welcome.

Well a budget and other goals or limitations, especially something like box size would be helpful.

Subwoofers are basically a question of cost and size. Horn subs of one sort or another can be extremely powerful and efficient, but tend to be large. You can go much smaller, but require more power and more expensive drivers.

People have built essentially entire walls as subwoofers. So there's quite a wide range. WinISD is a good calculator for doing the basic woofer/subwoofer performance calculations. You pop in the characteristics of the driver and you can then experiment with box size and power.

Drivers range in cost from $50-$1000+. So, some guidance as to how much you want to spend is necessary. Your driver will also determine how much power you can use. Remember that the power doubles for every 3db increase in SPL. So an amp with 100w will get you a volume essentially half as loud as 1000w amp. So there's a strong element of diminishing returns on that end of things, which is why people tend to go for multiple woofers/subwoofers when seeking powerful bass.
My idea is two woofers in parallel like Watt & Puppy, but I'm oper to other ideas/suggestions. Drivers range cost not the more expensive: I'm looking the best relation cost/quality. My mono power amps are Erno Borbely 75W RMS @ 8 Ohms.

Not the more expensive and best cost/quality is not useful information. Since very few people want to buy the most expensive or the worst cost/quality.

You need to tell us

a) Some sort of a budget range ($50-$100 or $100-$250 or $250-$500). At a minimum for the drivers and preferably the box for the woofers/subwoofers.

Expect to pay $150-$300 for a good woofer. But again, it depends on what you want in terms of performance. If you don't need 110db at 20hz, you can spend less money and get acceptable performance.

b) Maximum size of the box for the woofers/subwoofers. Keep in mind that a good subwoofer box, especially with nice wood working can be several hundred dollars on it's own. On the other hand, it's possible to get flat packs of a box you can put together for a fraction of that, but it just won't look as nice.

Obviously, a 15" or 18" woofer is going to affect the size of the box you'll need vs a 10" or 12". Also not all drivers perform equally well in the same size box. There is also if you will have a ported or sealed box to consider.

c) A SPL target at a minimum frequency.

Basically two of the same drivers will get you a 3db increase in SPL or essentially the same as doubling the power.

Tube amps aren't a great match for woofers, especially low power ones. I'd strongly consider some other sort of amp for the subs/woofers. Low frequencies can take a LOT of power.

If you want this to be a three way, you need to determine the lower crossover point from your mid range to the woofer. I don't know what your 2 way crossover is designed to have as the lower cutoff point for your speaker.
Hi merlin, Generic,
Nice drivers. :)

2. VIFA PL22WR09-08

in order
enclosure (br) volume:
2. VIFA PL22WR09-08, VB = 31.7 L
3. PEERLESS HDS NOMEX 830869, VB = 52.0 L
1. SB ACOUSTICS SB23NRXS45-8, VB = 70.1 L
4. SEAS CA22RNX, VB = 89.5 L.

in order
1. SB ACOUSTICS SB23NRXS45-8 & 3. PEERLESS HDS NOMEX 830869 > 89.5 dB/2.83V/m
4. SEAS CA22RNX > 89.2 dB/2.83V/m
2. VIFA PL22WR09-08 > 87.7 dB/2.83V/m.

in order
lower fr. extensions:
4. SEAS CA22RNX, f3=32 Hz, f24=12 Hz, 20Hz/~8dB attenuation
1. SB ACOUSTICS SB23NRXS45-8, f3=32 Hz, f24=12 Hz, 20Hz/~9dB attenuation
3. PEERLESS HDS NOMEX 830869, f3=36 Hz, f24=13 Hz, 20Hz/~11dB attenuation
2. VIFA PL22WR09-08, f3=37 Hz, f24=13 Hz, 20Hz/~12dB attenuation.

in order
max. [email protected] m:
4. 104.9 dB
1. 104.6 dB
3. 104.1 dB
2. 101.9 dB.
two woofer in parallel for each loudspeaker --^^

1. 139.5 L enclosure and sensitivity ~95.7 dB/2.83V/m
2. 64.1 L enclosure and sensitivity ~93.8 dB/2.83V/m
3. 104.1 L enclosure and sensitivity ~95.7 dB/2.83V/m
4. 176.5 L enclosure and sensitivity ~95.4 dB/2.83V/m.

With more sensitivity for a passive system than you should, but OK if active +amp. close to [email protected]~3.5 Ohms (for the 2xsubs).
So all work in tandem with your main driver in a 2 way. So are you using the same filter 2-Way or doing a 3-Way or what is your plan?! :confused:
What ever happens is going to be an interesting configuration. :D
I have problems calculating box measures to Liters, could you give an idea wich one will be better suited for my two way box that measures 30,5cm x 34cm, attached pics just for fun:)


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I think one woofer (with one inductor+rc maybe) could work, but I don't know what you have in mind. In this case I would test the (1x) SB ACOUSTICS for sub and adjust variant internal R in the L1 coil for the main driver.
If for one driver as above (30,5cm x 34cm ext.) for 70 L.
Height in cm: 95, Width in cm: 30.5, Depth in cm: 34, thickness in cm: 2.2
Strassacker: Speaker Building, Components
You can use any vol. calculator.
The thicknes of the wood is 2 cm, the rest of measures are:

High 36 cm
Top 13,5 cm width

The internal structure is Matrix type;), attached pics, the left side pic is the tweeter hole so the loudspeaker have three braces internally all with holes.


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