Hello!
I bought about a year and a half ago some SB Acoustics drivers. I haven't found the time to build the speakers untill now. But I managed to get a 1 week vacation, got my best friend to help me build them (I have 2 left hands) and started to work.
The speakers are:
2 x SB Acoustics :: SB29RDC-C000-4
2 x SB Acoustics :: 6" SB17NRXC35-4
4 x SB Acoustics :: 8'' SB23NRXS45-8
I have simulated the speaker using Boxsim and both the manufacturer's FR graphs and the graphs form Zaph|Audio
Results:
Frequency Response:
Phase:
Directivity:
The crossover:
I considered they are looking good, so I started to build the enclosures:
And the crossovers:
I bought about a year and a half ago some SB Acoustics drivers. I haven't found the time to build the speakers untill now. But I managed to get a 1 week vacation, got my best friend to help me build them (I have 2 left hands) and started to work.
The speakers are:
2 x SB Acoustics :: SB29RDC-C000-4
2 x SB Acoustics :: 6" SB17NRXC35-4
4 x SB Acoustics :: 8'' SB23NRXS45-8
I have simulated the speaker using Boxsim and both the manufacturer's FR graphs and the graphs form Zaph|Audio
Results:
Frequency Response:
Phase:
Directivity:
The crossover:
I considered they are looking good, so I started to build the enclosures:
And the crossovers:
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hi,
ive tried simulated the volume for sb23, i found out that the best encl is within 60-70L each, from the look of your cabs, im guessing its about 60-80L??
how is the sound ? im kinda interested to use them, as they are well price and available at my place.
cheers
henry
ive tried simulated the volume for sb23, i found out that the best encl is within 60-70L each, from the look of your cabs, im guessing its about 60-80L??
how is the sound ? im kinda interested to use them, as they are well price and available at my place.
cheers
henry
Pair of those 8" in 60-70 lit closed box is one of my greatest experiences. Well braced box, rock wool filled evenly all volume...stunning bass.
Cheers, Jernej
Cheers, Jernej
Yes, 70 L (best) gives F3=32Hz. OP has it around 50/60Hz.
cosmindaniel12, did you use the drivers phase output in your frd/zma's data for Boxsim? Are you doing the finishings in your speakers? Nice build.
Henry - the enclosure is vented, around 70-75 liters, tuned at 30 Hz via a 105 mm tube, 30 cm long, in . The bass is pretty close to a sealed box, short and dry, not boomy. If I will change my mind, I can always seal them. But I like them like this!
Inductor - I did use the phase output. I will paint them.
Today was a rainy day, and that stopped me from working as much as I wanted on them. Tommorow we'll prepare them for painting. Progress so far:
Inductor - I did use the phase output. I will paint them.
Today was a rainy day, and that stopped me from working as much as I wanted on them. Tommorow we'll prepare them for painting. Progress so far:
It’s going to be nice build .I'd like to point at one detail. You have chosen the mid-woofer for midrange duties. Under acoustic load at high frequencies , plus your 350Hz high pass filter the maximal peak-to-peak excursion will not exceed 2mm for 60W power.
So the remaining 9mm of coil will work like ballast. From other viewpoint we can say that the speaker has low BL/Sd ratio. From here goes worse dynamics in midrange region and not very articulated vocals. Nothing wrong , just think about it.
So the remaining 9mm of coil will work like ballast. From other viewpoint we can say that the speaker has low BL/Sd ratio. From here goes worse dynamics in midrange region and not very articulated vocals. Nothing wrong , just think about it.
Moon Track: I am aware of the mentioned limitations. Using a midwoofer as a midrange driver isn't that uncommon. I think this driver (the SB17) has one of the best midranges around it's price.
Hello Daniel.
I just can say from my experience. If we will take speaker’s force factor BL deleted by Sd(in cm2), speakers with result 0.03-0.06 do not inspire me by their dynamics and resolution in midrange region. And I absolutely adore those speakers with coefficient 0.1 and higher. It is all for speakers separated from twitter at 3.5-5kHz.
It’s early to call it limitation without serious math.
You have pretty low crossover point between midrange and twitter.
The low pass filter itself limits too dynamical peaks , most dynamics will be reproduced by twitter and possible you couldn’t notice a difference.
I just can say from my experience. If we will take speaker’s force factor BL deleted by Sd(in cm2), speakers with result 0.03-0.06 do not inspire me by their dynamics and resolution in midrange region. And I absolutely adore those speakers with coefficient 0.1 and higher. It is all for speakers separated from twitter at 3.5-5kHz.
It’s early to call it limitation without serious math.
You have pretty low crossover point between midrange and twitter.
The low pass filter itself limits too dynamical peaks , most dynamics will be reproduced by twitter and possible you couldn’t notice a difference.
Looking great, good job. Indeed a more suitable midrange could've made job on xover easier but if you like it, enjoy it.
I like the inclination, does it achieve temporal alignment?
I like the inclination, does it achieve temporal alignment?
If you referring to the vertical position (x, y, z) in space relative between drivers (coils or frames) and baffle, yes, the Boxsim software has that possibility for data input and it should reflect on the phase/output time alignment, if correct. OP must be aware of it, as he might answer you soon.😀
Yes, the speakers are reclied for temporal alignment.
Progress was slow, but still:
Progress was slow, but still:
And the speakers are now complete. They sound great on classical music and jazz, but the tweeter is still a couple of dB too loud for rock, or other styles. I'll try some more different resistors, to find something that suits my very small and reflective room.
They were designed for a medium-large living room, but for the moment I use them in a small room (around 18 mp - 200 sq ft).
Pictures:
They were designed for a medium-large living room, but for the moment I use them in a small room (around 18 mp - 200 sq ft).
Pictures:
Very nice build. Congrats. You know... classical and jazz is all that matters.heheh (joking)
Loud tweeter. You should know when you simulated the (very commercial) catenary speaker output. The bass will improve a little with time, but you will prob. need +/-2 dB attenuation. Use a shoulder pad in the meantime.
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I have changed the tweeter and mid attenuation, moved the speakers around the room, found their best place in the room, and now I'm absolutely happy with them.
Final crossover:
Out of curiosity, I measured them using HOLMImpulse and my old mic, bonus for an ASUS motherboard:
The mic measures surprisingly linear. If I'm measuring the drivers independently, I get results within 2 dB from the simulation. The down side is that it only measures to 10kHz.
Frequency response in the listening position, 1/3 octave smoothing:
THD:
2nd HD
3rd HD
4th HD
5th HD
Final crossover:
Out of curiosity, I measured them using HOLMImpulse and my old mic, bonus for an ASUS motherboard:
The mic measures surprisingly linear. If I'm measuring the drivers independently, I get results within 2 dB from the simulation. The down side is that it only measures to 10kHz.
Frequency response in the listening position, 1/3 octave smoothing:
THD:
2nd HD
3rd HD
4th HD
5th HD
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Now please listen to the 50/100 CD's or vinyls that you have and report back. Please don't touch anything in the mean time before posting... crossover upgrades are permitted only by the diy forum rules after 1 year or two.😀😀😀
Well, here's the first report:
I only got to listen to them late at night, so "quiet" music (Classical and jazz), at modest levels. My girlfriend, on the other hand (who btw loves them), got to listen to them during the day. And she listened only to some 100+ dB, so she handled the burn-in.
Just after I built them, and during cross-over adjustments, the mids and highs were great, but the bass was just ok. I liked that it was short, dry thumping, but the impact and lower extension were just decent, if not a tiny bit dissapointing.
Last night, I got home in the mood for some Linkin Park. When the music started, the bass extension and impact was just jaw-dropping! I started looking at the tone controls, foobar equalizer, my soundcard equalizer, thinking that my gf might have "adjusted" the bass... They were all still flat!
I guess that what I'm trying to say is: if you'll ever use these woofers, allow them some good days for burn-in! Do not judge them right away!
As for the mids and highs, they remained just great (to my taste)!
I only got to listen to them late at night, so "quiet" music (Classical and jazz), at modest levels. My girlfriend, on the other hand (who btw loves them), got to listen to them during the day. And she listened only to some 100+ dB, so she handled the burn-in.
Just after I built them, and during cross-over adjustments, the mids and highs were great, but the bass was just ok. I liked that it was short, dry thumping, but the impact and lower extension were just decent, if not a tiny bit dissapointing.
Last night, I got home in the mood for some Linkin Park. When the music started, the bass extension and impact was just jaw-dropping! I started looking at the tone controls, foobar equalizer, my soundcard equalizer, thinking that my gf might have "adjusted" the bass... They were all still flat!
I guess that what I'm trying to say is: if you'll ever use these woofers, allow them some good days for burn-in! Do not judge them right away!
As for the mids and highs, they remained just great (to my taste)!
