I have been checking out box calculators to turn my sealed subs into ported ones.
I realise that box volumes will need to be different, eventually, but I cant understand why different calculators give such wildly different port size and length results.
I have been using the DIY Audio Speaker box enclosure designer/calculator and this one
HiFi Loudspeaker Design
Even if the calculated box sizes are similar, the vent sizes are often different and the lengths as well.
Even when I recalculate for different sized vents (to make them at least one-third the diameter of the cone), I'm getting quite different results.
I have been using the Dayton specs from Parts Express (for three drivers, RSS390HO-4, RSS265-HO 44 and RS270P-4A).
Clearly I'm missing something here.
Or should I just rely on the DIY Audio calculator and leave it at that?😕
I realise that box volumes will need to be different, eventually, but I cant understand why different calculators give such wildly different port size and length results.
I have been using the DIY Audio Speaker box enclosure designer/calculator and this one
HiFi Loudspeaker Design
Even if the calculated box sizes are similar, the vent sizes are often different and the lengths as well.
Even when I recalculate for different sized vents (to make them at least one-third the diameter of the cone), I'm getting quite different results.
I have been using the Dayton specs from Parts Express (for three drivers, RSS390HO-4, RSS265-HO 44 and RS270P-4A).
Clearly I'm missing something here.
Or should I just rely on the DIY Audio calculator and leave it at that?😕
Hmmm, the first recalc using the DIY box designer seems to be giving better bass output results with the RS270P-4As than with the former box simulator.
So I might check out how the others perform with the new (longer) ports.
So I might check out how the others perform with the new (longer) ports.
1. They design to different alignments.
2. Some traditional alignments do not make sense for modern woofers. Some woofers are designed for a small closed box and rely on an electronic equalizer for obtaining a flat frequency response, yet the traditional alignment dictates a vented enclosure with an impossibly long port.
3. The alignment dictates the tuning frequency, but vent diameter is a free parameter that must be set by the user. Once it is given, the software calculates the corresponding tuning frequency. Flare-it can calculate the minimum port diameter at which chuffing is no problem. Flare-it - Free Speaker Design Software
I think box calculator is a bad description and box simulator is better. The software require user input for box size, tuning frequency etc. and then simulates the frequency response. It starts off with a traditional alignment, which optimizes for a flat frequency response at the cost of everything. The user then must balance frequency response flatness, power handling, box size, low frequency extension, port air velocity, efficiency etc.
2. Some traditional alignments do not make sense for modern woofers. Some woofers are designed for a small closed box and rely on an electronic equalizer for obtaining a flat frequency response, yet the traditional alignment dictates a vented enclosure with an impossibly long port.
3. The alignment dictates the tuning frequency, but vent diameter is a free parameter that must be set by the user. Once it is given, the software calculates the corresponding tuning frequency. Flare-it can calculate the minimum port diameter at which chuffing is no problem. Flare-it - Free Speaker Design Software
I think box calculator is a bad description and box simulator is better. The software require user input for box size, tuning frequency etc. and then simulates the frequency response. It starts off with a traditional alignment, which optimizes for a flat frequency response at the cost of everything. The user then must balance frequency response flatness, power handling, box size, low frequency extension, port air velocity, efficiency etc.
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Try WinISD---it's a free speaker enclosure design program:
WinISD - Linearteam
and see what results you get.
WinISD - Linearteam
and see what results you get.
So I borrowed the lad's almost dead laptop and managed to download WinISD.
Oddly, no data for Dayton drivers; perhaps they're "too new"?
Anyhow, after inputting the data for the 15-inch RSS390HO, I got v similar vent diam and length to the figures generated by the DIYaudio box sim.
Will now repeat for the RSS265HO-44 driver (10-inch sub). Thx for the steer.
Oddly, no data for Dayton drivers; perhaps they're "too new"?
Anyhow, after inputting the data for the 15-inch RSS390HO, I got v similar vent diam and length to the figures generated by the DIYaudio box sim.
Will now repeat for the RSS265HO-44 driver (10-inch sub). Thx for the steer.
Just get Wine or Crossover trail (the last if your running a 64-bit only OSX). It will run WinISD just fine on your Mac.
Also note that WinISD will not just give you a single alignment. You can fine tune it based on your needs and woofer abilities. Also take into account that if you’re using a plate amp they often come with some added filters. WinISD can also simulatie those. What exactly are you looking for?
Also note that WinISD will not just give you a single alignment. You can fine tune it based on your needs and woofer abilities. Also take into account that if you’re using a plate amp they often come with some added filters. WinISD can also simulatie those. What exactly are you looking for?
Actually, I have a couple of pairs of 10-inch drivers and in sealed enclosures weren't quite developing enough visceral bass. So I wanted to see if I could extract a bit more oomph simply by porting them. And I have, though I'm led to believe I really need enclosures twice the size for ported speakers compared with sealed.
Anyhow even as they are, they seem improved to me. I'd always steered clear of ported enclosures because of reports of one-note bass etc, but in the enclosures I use Im not getting that. They are essentially bent cylinders, with routed wooden end caps.
As in the attached (the white Minion-like enclosures behind the waveguide speakers).
Anyhow even as they are, they seem improved to me. I'd always steered clear of ported enclosures because of reports of one-note bass etc, but in the enclosures I use Im not getting that. They are essentially bent cylinders, with routed wooden end caps.
As in the attached (the white Minion-like enclosures behind the waveguide speakers).
Attachments
Forgot to mention; not using a plate amp, although the 15-inch sub has its own Gallo Ref stereo sub amp).
The waveguides are driven by a chip amp, and the 10-inch woofers by N-Core 200wpc amps. Active crossover, only using low pass set at 200Hz. So separate volume controls for waveguides and woofers.
The waveguides are driven by a chip amp, and the 10-inch woofers by N-Core 200wpc amps. Active crossover, only using low pass set at 200Hz. So separate volume controls for waveguides and woofers.
Feel like Im really getting somewhere now. Have settled on the RSS265HOs as the better drivers for solid bass, and am using an active crossover set at 200Hz for both these and the 15-inch sub. Plus a bit of tweaking to DSP in Roon and I think we are cooking with gas on the bass front, even at real low volumes.
The longer ports sound more correct to me too. Next I will try out bigger enclosures for the 265HOs, according to what the sims and the specs say.
Again, thx for the help offered.
The longer ports sound more correct to me too. Next I will try out bigger enclosures for the 265HOs, according to what the sims and the specs say.
Again, thx for the help offered.