When you mentioned you "think" 50hz is really missing, do you have any actual measurements to backup your claim?
For me personally, because the NBAC series and CAC series perform VERY similar for a fraction of the price.
But I would also almost never use such drivers for low-end as well, but always use it with a subwoofer.
Even implemented in the same cabinet or so.
I personally also find the looks of Textreme fugly, really kitsch.
Which is very personal taste obviously.
Last edited:
Yes, all the dips and erratic behavior is from interference from their room.
Super typical.
No idea why they leave it in there, it blurs the graphs quite dramatically in some cases.
I'm designing with the Textreme woofers and Satori TX and BE tweeters. I'll probably have something out next summer. I know other people are using them too.
Thanks for all the replies!
I used an Android APP, Frequency Sound Generator, that has three iPod-like finger-knobs for frequency sweep and loudness comparison. With the driver semi-mounted on my 17L 1.5m 5:1-tapered TL ("TLonken") facing upward, my nose against the baffle, left ear over the driver cone, right ear over the TL port (a slight head-turning brought one ear right on top) -- I confirmed the FR valley centered at 50hz. For speaker-DIY I have amp-pairs/quads with 1db-stepped volume controls (not verified for accuracy), TPA3221, TA2024, etc. if needed. Playing music with bass, the shortcoming is audible. (This TLonken design supports my 8" drivers down to 40hz plus/minus. If 60hz is the lower limit then I may as well use a smaller cab.)
Yes I had read a partial sentence or two quickly dismissing the 50hz valleys in official SB MW charts as (must be!) measurement artifact -- which I no longer believe to be the case. So I'm looking for experiences or ideas addressing this problem or similar. Unfortunately, the Textreme MWs seem to be used mainly as bigger MR :-(
I'm rather allergic to BR Helmholtz resonance but may just have to try 50hz and give up below.... That or re-do the TL quarterwave for 50hz but the valley/ravine is probably too deep for TL.
(p.s. when I searched earlier for Textreme on diyaudio forums the recent posts were for-sales.)
I used an Android APP, Frequency Sound Generator, that has three iPod-like finger-knobs for frequency sweep and loudness comparison. With the driver semi-mounted on my 17L 1.5m 5:1-tapered TL ("TLonken") facing upward, my nose against the baffle, left ear over the driver cone, right ear over the TL port (a slight head-turning brought one ear right on top) -- I confirmed the FR valley centered at 50hz. For speaker-DIY I have amp-pairs/quads with 1db-stepped volume controls (not verified for accuracy), TPA3221, TA2024, etc. if needed. Playing music with bass, the shortcoming is audible. (This TLonken design supports my 8" drivers down to 40hz plus/minus. If 60hz is the lower limit then I may as well use a smaller cab.)
Yes I had read a partial sentence or two quickly dismissing the 50hz valleys in official SB MW charts as (must be!) measurement artifact -- which I no longer believe to be the case. So I'm looking for experiences or ideas addressing this problem or similar. Unfortunately, the Textreme MWs seem to be used mainly as bigger MR :-(
I'm rather allergic to BR Helmholtz resonance but may just have to try 50hz and give up below.... That or re-do the TL quarterwave for 50hz but the valley/ravine is probably too deep for TL.
(p.s. when I searched earlier for Textreme on diyaudio forums the recent posts were for-sales.)
Last edited:
I must say I am pretty shock to hear you confirmed there is a FR valley centered at 50Hz just by using your ear. I must say I will be very impressed if you can differentiate between 40Hz, 50Hz or 60Hz by just using your ears. Just because the manufacturer spec shows a dip at 50Hz and you conclude that is actually happening to your speaker output. The best way to show it is to do a measurement to prove your point.
Just to show you it is all about speaker design, the 50Hz dip does not show up in a well design speaker. Here is a link to the SB Acoustics SASANDU Textreme Speakers using the Textreme drivers and it does not show any dip at the 50Hz region in the measured FR.
https://www.audiohobby.eu/en/loudsp...extreme-speakers-finetuning-by-stereoart.html
Just to show you it is all about speaker design, the 50Hz dip does not show up in a well design speaker. Here is a link to the SB Acoustics SASANDU Textreme Speakers using the Textreme drivers and it does not show any dip at the 50Hz region in the measured FR.
https://www.audiohobby.eu/en/loudsp...extreme-speakers-finetuning-by-stereoart.html
In case you did not notice, the 7.5" Textreme driver also has a dip at the 50Hz region and based on your theory it doesn't matter whether they are using 2 or 1 driver because the dip is already there in the manufacturer spec. That's why I said it is all about the design of the speaker. Such dip can happen if we are talking about room response.
Graph looks hopeful. (Where went HF breakup peaks?) I don't think the 1.5m-delayed TL port output causes cancellation of the direct driver output like BR below Helmholtz. At 57hz the 6m wavelength is 4X the TL, so the backwave becomes 90deg out-of-phase and combines with direct output at +3dB (if equal amplitude). At 60hz the gain is a bit more, at 50hz a bit less but still positive (until 38hz). At 43hz the TL gain is minimal but quarterwave resonance dominates cone output anyway. There are minor TL sub-segment resonances due to bends and folds but nothing that would create a valley around 50hz.
Near-field measurement is good -- I used my head and two ears plus volume-control to measure finger-traced tone-sweeps. In-room I surely cannot hope to exceed SB Acoustics in measurement accuracy, but playing music at 1m the lower bass notes aren't quite as satisfyingly complete.
Near-field measurement is good -- I used my head and two ears plus volume-control to measure finger-traced tone-sweeps. In-room I surely cannot hope to exceed SB Acoustics in measurement accuracy, but playing music at 1m the lower bass notes aren't quite as satisfyingly complete.
I have an full Textreme Sasandu active that I absolutely love. I would put them up against any speakers at any price. I am playing them full range and constantly get asked if I have my subs playing. The weird thing is you can't even see he woofers move. But they are cranking along at about 95db. The room is shaking but it doesn't even look like they are working at all. What an impressive speaker.
