Hi there!
I 3d printed a port computed with WinISD. Box is 2.83L of internal volume and tuned to 76.44. Port is 32mm x 12mm. I followed suggestions about making a port with the biggest area you can afford in the enclosure leaving a port diameter clearance. I really like the way it sounds, if I compare with the PS95 after getting the recommended passive elements to tame the peaks.
Questions:
Thanks.
I 3d printed a port computed with WinISD. Box is 2.83L of internal volume and tuned to 76.44. Port is 32mm x 12mm. I followed suggestions about making a port with the biggest area you can afford in the enclosure leaving a port diameter clearance. I really like the way it sounds, if I compare with the PS95 after getting the recommended passive elements to tame the peaks.
Questions:
- Do you like this rule and if so, does it apply to small speakers? With 5W I get port wind speed = 14.
- Is it better to model to the max wattage you are planning to use and have speed close to 20?
- Is the frequency response acceptable? Can I do better with a speaker this size?
Thanks.
there is certainly something wrong with that suckout between 1kHz and 150Hz, that is 15dB down compared to the rest. This driver measures better in all other measurements i've seen of this driver. You can see measurments made by a forum member in post 53 here: https://www.diyaudio.com/community/threads/new-fullranger-alert-tang-band-3-4.276429/page-3
A 2.8L also should go to about 77Hz F3 with a 4cm port of 20cm long say simulations, yours cut off way to early.
A 2.8L also should go to about 77Hz F3 with a 4cm port of 20cm long say simulations, yours cut off way to early.
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Thanks for the reply waxx. When I put 4cm as port diameter I got (almost) the same port length you computed. It doesn't fit my box, but other than that, is there any reason to choose it over other port dimensions? Wondering if the rule of thumb I'm following holds.
wel, you want a port that does not start compressing or chuffing (making noise due to a too high air velocity). 4cm is the smallest diameter i would use, and then the port length is what it is for a right tuning. And rule of thumps never work perfectly. Speaker building is physics, and based on mathematical calculations, not guessing.
Thanks a lot. Not guessing... That's what I got for 5W in WinISD (Max 14). 5W is enough for what I want.
I will echo waxx, that there is a problem with the driver or the build, looking at that FR.
I know I would hate the sound. That's a chasm in the mids, and would certainly hurt my ears.
I'd measure everything again, driver in free air, impedance in free air and in the enclosure, double check the BSC parts and implementation. There is no way that TB driver would look like that in the right box.
I know I would hate the sound. That's a chasm in the mids, and would certainly hurt my ears.
I'd measure everything again, driver in free air, impedance in free air and in the enclosure, double check the BSC parts and implementation. There is no way that TB driver would look like that in the right box.
Purely a WAG, but between the driver recessed in a 'bowl' combined with the acoustically large vent protruding, somewhat overlapping, forward of the driver, can 'see' why it might be the dominant/damping (albeit comb filtering) 'radiator' in the critical mids BW.
Thanks a lot. I have a better box with the same dimensions and the port is not close. I should try after work.
I remembered I was told once to measure in the center of the room, 1m high and at 50cm of the speaker. I got some measurements with the port open and closed. Looks different than in the previous measurements. Port tuning seems off, I will double-check if I'm measuring volume the right way.
