Hi @EmuMannen I browsed your blog -- some interesting comments. What is this Vituixcad "psychoacoustic curve" that you mentioned when tuning your crossover?
I don't think I mentioned a psychoacoustic curve in VituixCAD but I often refer to psychoacoustic smoothing applied in REW. You can apply the following types of smoothing in REW:
- 1/1 Octave Smoothing
- 1/2 Octave Smoothing
- 1/3 Octave Smoothing
- 1/6 Octave Smoothing
- 1/12 Octave Smoothing
- 1/24 Octave Smoothing
- 1/48 Octave Smoothing
- Variable Smoothing
- Psychoacoustic Smoothing
- ERB Smoothing
Psychoacoustic smoothing uses 1/3 octave below 100Hz, 1/6 octave above 1 kHz and varies from 1/3 octave to 1/6 octave between 100 Hz and 1 kHz. It also applies more weighting to peaks by using a cubic mean (cube root of the average of the cubed values) to produce a plot that more closely corresponds to the perceived frequency response.
ERB smoothing uses a variable smoothing bandwidth that corresponds to the ear's Equivalent Rectangular Bandwidth, which is (107.77f + 24.673) Hz, where f is in kHz. At low frequencies this gives heavy smoothing, about 1 octave at 50Hz, 1/2 octave at 100 Hz, 1/3 octave at 200 Hz then levelling out to approximately 1/6 octave above 1 kHz.
I’m currently looking for some active speakers and found your post interesting. Curious why you switched?I made the switch from 2-way active speakers with active line level crossovers to 3-way speakers with passive crossovers recently.
I'm not a fan of complex crossovers at speaker level (ruling out most of Troels' other designs), which is why I chose the CNO Grande with its 1st order crossover. The favorable reviews of the W18NX003 supported the decision. See https://hificompass.com/en/reviews/seas-excel-6-w18nx003-e0096-08-midwoofer-review for example.
The same source has a favorable review of the Purifi driver (both 8R and 4R version): https://hificompass.com/en/reviews/purifi-ptt65w08-01b-ptt65x08-nfa-01
Either way, this being a DIY site, I can't quite relate to all the recommendations for going the commercial route. Then again, since I lack the tools, space and frankly also the skills to make an enclosure that would've satisfied my building standards, I got the cabinets made by a carpenter. It's kinda like getting the drilled and tapped amp enclosures from the diyaudiostore methinks, so I'm still calling them DIY speakers
What actives were you using?
I’ve considered diy but I too may not have the skills. I did look at Purifi and D class amplification. Just want to experience actives and hear how they compare to passive.
Dynaudio Xeo currently has my attention. Considered Kef but trying to stay away from metal cone’s.
Suggestions?
Thanks
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I was using a SEAS U18RNX/P with a Morel ST728 in a tapered quarter wave transmission line enclosure. 3rd order active line level crossover with BSC. Amplification varied between Class A amps like the diy Sony Vfet and a mini Aleph J, and a pair of LM4780/3886 chipamps.
I switched to a three way speaker with passive XO (1st order however) because I wanted something new and possibly better, and something that I can power from a single low wattage amp.
Some days I miss the old setup, most days I don't
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With passive speakers I’ve always struggled with matching them to an amplifier. Supposedly that part of the equation is eliminated with active speakers.?
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hello,
Troels' latest project, the Fusion 22 makes me really want it. I love this speaker format. I don't see the cutoff frequencies anywhere...
What do you think ? the Hp choose are top of the range.
do you think this kind of achievement? expensive can compete with speakers like Harbeth M40, yamaha ns 1000 ......
Troels' latest project, the Fusion 22 makes me really want it. I love this speaker format. I don't see the cutoff frequencies anywhere...
What do you think ? the Hp choose are top of the range.
do you think this kind of achievement? expensive can compete with speakers like Harbeth M40, yamaha ns 1000 ......
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Finalists....
Anyway people should understand is you must listen to a loudspeaker before signing. Do you lice with wife, car, diving devices, etc... without having tried it yet ?
You can begin to make comparaison with experience only and alas it comas at a price (a pleasure as well if it is your hobby)
Check out the Travelers. Those are supposed to compete with the Bordeaux in the mid range.
You'll have to look them up on I believe HT guide or parts express forum.
Curt wrote a few posts regarding the mid-range tunnel design and his goals with using that technique. It's a very interesting read. I'll try to post it later today.
You'll have to look them up on I believe HT guide or parts express forum.
Curt wrote a few posts regarding the mid-range tunnel design and his goals with using that technique. It's a very interesting read. I'll try to post it later today.
If you have concerns about the load presented to the amplifier, know that speaker drivers have a varying impedance even without a crossover. Ironically you would have to add passive components to make it appear as a resistive load to the amp.
Here is that post that I was talking about. Starts at #12 and he chimes in a few more times.
https://techtalk.parts-express.com/...31301-designing-an-open-back-midrange-speaker
https://techtalk.parts-express.com/...31301-designing-an-open-back-midrange-speaker
Spot on, the same reason i use aperiodic midTLs, they tend to suck up the entire back wave.
His suggestion of how to design it, seems to be overkill.
I use a 10-1 tapered TL as deep as the enclosure… given an XO of typically >200-250 Hz XO the effective length (remember a tapered line [smaller at the terminus) has an efective length lof the line is onger than a cyclinder of the same length.
If it is still not long enuff fold it back on itself.
This is the midTL out of our A12pw MTM.
dave
It's easier to joke separate internal enclosure fir the mid.
I'd prefer the conventional arrangement where the mid is next to the woofer from an acoustic perspective.