Hi! then the only option i have is sealed enclosure?
what would be the sound quality? satisfactory or good enough? Any advice you want to give? please. regards.
Go to this page and see how Vb is defined.
The Subwoofer DIY Page - Box-Building FAQ
Is what you refer to as "free air volume" the same as Vb?
Yes. i meant inside volume of the speaker enclosure. 1.64cubic foot is total volume of the enclosure.
approx 1cubic foot+ is inside volume of the box.
Last edited:
Niru,
I agree with the other folks wo are suggesting sealed. 1 cu ft sealed will give you the best "clean" sounding speaker, but it will need a subwoofer below 100Hz to give satisfying sound. If you are planning to use this, say 12in from a back wall and placed 39in high (driver centerline), and you sit 2.5m away - you might get more of a sense of bass, albeit with some extra punch at 110Hz which is not a bad thing as it gives impact, then try adding a 3in dia vent x 3in long. Still put some loose stuffing in the speaker though. Assuming 28.3L (1 cu ft) internal volume, this is sort of what it might look like. Also needs a baffle step compensation (BSC) filter using a 1mH choke and 6.8ohm 10w resistor in parallel, and both then in series between driver and amp. Without the BSC, it will sound too bright:
Same speaker sealed:
I agree with the other folks wo are suggesting sealed. 1 cu ft sealed will give you the best "clean" sounding speaker, but it will need a subwoofer below 100Hz to give satisfying sound. If you are planning to use this, say 12in from a back wall and placed 39in high (driver centerline), and you sit 2.5m away - you might get more of a sense of bass, albeit with some extra punch at 110Hz which is not a bad thing as it gives impact, then try adding a 3in dia vent x 3in long. Still put some loose stuffing in the speaker though. Assuming 28.3L (1 cu ft) internal volume, this is sort of what it might look like. Also needs a baffle step compensation (BSC) filter using a 1mH choke and 6.8ohm 10w resistor in parallel, and both then in series between driver and amp. Without the BSC, it will sound too bright:
Same speaker sealed:
Attachments
Last edited:
My best friends call me NiruNiru,
I agree with the other folks wo are suggesting sealed. 1 cu ft sealed will give you the best "clean" sounding speaker, but it will need a subwoofer below 100Hz to give satisfying sound. If you are planning to use this, say 12in from a back wall and placed 39in high (driver centerline), and you sit 2.5m away - you might get more of a sense of bass, albeit with some extra punch at 110Hz which is not a bad thing as it gives impact, then try adding a 3in dia vent x 3in long. Still put some loose stuffing in the speaker though. Assuming 28.3L (1 cu ft) internal volume, this is sort of what it might look like. Also needs a baffle step compensation (BSC) filter using a 1mH choke and 6.8ohm 10w resistor in parallel, and both then in series between driver and amp. Without the BSC, it will sound too bright:
Same speaker sealed:
What a weird nameThe outer dimension of my box is- 19inch high, 11.5inch depth(side) & 13inch width(front).
the choke & resistor you mention, can i use for sealed?
i like diyaudio forum because of people like you.
thank you very much
My best friends call me Niru
The outer dimension of my box is- 19inch high, 11.5inch depth(side) & 13inch width(front).
the choke & resistor you mention, can i use for sealed?
i like diyaudio forum because of people like you.
thank you very much
Assuming 0.75in thick material, I calculate a volume of only 0.75cu ft for your box. That’s different than 1cu ft and probably okay with vent - maybe 4in long. BSC filter works for both sealed or bass reflex as works above 800Hz or so. Reran sim and optimized for 0.75 fu ft. You can actually get a decent response now.
For BSC filter, use 5ohm 10W + 1mH (assume DCR of ~0.7ohm typical for 20ga copper but 18ga at 0.4ohm ok too) and 3in dia x 5in long vent (vent on front baffle). Install speaker on a stand or shelf such that driver front is 12in from back wall and 39in from floor, gives an 87dB at 2.83vrms and 1m away with -6dB at 60Hz and -10dB (F10) at 35Hz. Should sound quite full and satisfying.
Attachments
Last edited:
Assuming 0.75in thick material, I calculate a volume of only 0.75cu ft for your box. That’s different than 1cu ft and probably okay with vent - maybe 4in long. BSC filter works for both sealed or bass reflex as works above 800Hz or so. Reran sim and optimized for 0.75 fu ft. You can actually get a decent response now.
For BSC filter, use 5ohm 10W + 1mH (assume DCR of ~0.7ohm typical for 20ga copper but 18ga at 0.4ohm ok too) and 3in dia x 5in long vent (vent on front baffle). Install speaker on a stand or shelf such that driver front is 12in from back wall and 39in from floor, gives an 87dB at 2.83vrms and 1m away with -6dB at 60Hz and -10dB (F10) at 35Hz. Should sound quite full and satisfying.
Wow!! Yes 3/4 (.75)inch mdf. But i thought it has 1cubic foot of space(i deduct approximate volume of driver, wood bracing etc). With due respect are you sure?
[*Outer dimension- 19inch high,
13inch width(front side), 11.5inch depth(side wall)].
If i am wrong then i should go for vented.
is it possible to use two × 2inch port?
1mH choke is little expensive in online & hard to work with such fine copper wire(100+ turn?). can i bypass it by active eq/tone control?
Regards.
My mistake - you have over 1cu ft and as you say, about 1 cu ft after deduction of bracing and driver etc. just go with 3in vent then, but okay around with 5ohm to 6.8ohm resistor an d see what sounds best to your ears. 1mH choke with 20ga copper is not expensive.
You can split into 2 smaller vents - match cross sections area. If not you can adjust length. Play with it and see what sounds good.
Plot just shows whatever name I save file as but not what I actually ran, as it is modified on the fly.
Even ferrite core can work. This one is 0.5ohm DCR and passes 3amps.
5pcs/18mm 6826D 1MH 0.5 Line 3A Iron core Magnetic ring inductors Annular Winding inductors-in Inductors from Home Improvement on Aliexpress.com | Alibaba Group
Here is air core:
Jantzen 1056 1.0mH 20 AWG Air Core Inductor 696554349636 | eBay
You can split into 2 smaller vents - match cross sections area. If not you can adjust length. Play with it and see what sounds good.
Plot just shows whatever name I save file as but not what I actually ran, as it is modified on the fly.
Even ferrite core can work. This one is 0.5ohm DCR and passes 3amps.
5pcs/18mm 6826D 1MH 0.5 Line 3A Iron core Magnetic ring inductors Annular Winding inductors-in Inductors from Home Improvement on Aliexpress.com | Alibaba Group
Here is air core:
Jantzen 1056 1.0mH 20 AWG Air Core Inductor 696554349636 | eBay
Last edited:
i deduct an approximate value of displacement(20%).
it was just a joke nothing more, don't mind.
i thought eq/tone control can help instead of choke network.
Ok, it's nice to meet you. again i must thnk u for all of your effort helping me
Edit: i forgot, what would be the port tuning frequency for 1cubic foot Bv? I'll calculate it by online calculator.
Last edited:
Probably tune for about 50Hz to 55Hz but could be as high as 65Hz. I would not know unless I plotted the cone excursion vs frequency and then look for the minimum point between two peaks (that’s the Fb “box” frequency). I actually don’t tune the vent to a frequency, but tune vs the overall response shape. You should start with the suggested 3in dia x 3in long vent and adjust in small increments. My simulation will be more comprehensive than a regular bass reflex calculator as it includes effect baffle step loss, the baffle step correction (BSC) filter, and the effects of the back wall and floor bass reinforcement. If you want to use a BR calculator, then you did not need the assistance of my simulator which uses Akabak.
Last edited:
i know your simulation software is far better than online crap!
the suggested vent of 1×3inch dia 3inch long gives around 60hz according to online calculator.....& with 2×2inch dia 3.25inch long gives same 60hz tuning.yeah, at first I should observe & adjust with fine tuning & in small increments. ok..bye friend.
[7.75*9]^0.5 = ~8.352 dia. = [8.352^2*pi/4] = ~54.782"^2 *2.54"^2 = ~353. 4316 cm^2 [Sd].
GM
the manufacturer is SWETON. there is no model no
Actually, there is
; 100 WT woofer [scroll down]: Sweton -Transducers Since 1982 ::Woofer Series - Pro Loudspeakers || Home LoudspeakersNote that when using Sd, Re, Mmd, BL to calculate specs, they're quite a bit different according to Hornresp, though in power sims are identical when tuned to the lower Fs:
Fs = 45.82 Hz
Qes =0.54
Qms = 5.10
Qts = 0.49
Vas = 53.97 L
If true, with a 0.7 mH @ 1 kHz, this implies an above average quality.
Assuming a reasonable 5 mm Xmax, peak power is limited to its 200 W peak music power when tuned to Fs, so not much low bass, but plenty of mid-bass for 'slam'/'punch' [the original 'low bass' on vinyl, etc..].
GM
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.