witwald, jcga: your prediction was confirmed, after thhe first two listening sessions I had to increase tweeter level by ~0.5dB. The overall presentation was too polite, lacking the drive and sparkle. More listening sessions will be done, speakers still need burn in. I will need to look at woofer alignment, and possibly lower midrange area, for some songs the bass is not entirely right, from my previous experiences this will take some time to get it right by experimenting with damping inside the cabinet and port tuning. Right now it seems I will need to add some damping material.
I still have the sound of Ellips-A (32W revelator in closed box) and I would like to get similar result from Shamal, which might be difficult.....
I still have the sound of Ellips-A (32W revelator in closed box) and I would like to get similar result from Shamal, which might be difficult.....
I really like those commercial speakers with treble adjustment knobs/switches. I think it really helps. Because I believe that the spectral balance or tilt depends on playback level or room furnishings etc, though I don’t have any evidence to support that.
All the audio tomfoolery hoodoo voodoo of using cable risers, changing cables and cable risers and DAC amps and disc players sources for “synergy” may have have been avoided with a few extra resistors and a switch built into the system.
All the audio tomfoolery hoodoo voodoo of using cable risers, changing cables and cable risers and DAC amps and disc players sources for “synergy” may have have been avoided with a few extra resistors and a switch built into the system.
Last edited:
In the good old days every amp had tone controls, as well as many expensive hifi speakers. Those were really needed because vinyl cartridges and cassette decks had so haphazard treble performance, and speakers had poor bass. Somehow during 90s tone controls disappeared, after PEQ had reneissance in 80s.
I guess "hifi" enthusiasts started to hate PEQ somehow, this lead to "pure" sound ideal without any extra potentiometers etc. on the pathway to deteriorate sound and add noise? In my eyes this was the reason why so many people buy new speakers, amps, dacs and interconnects many times a year, to find the sound they like. When the bass or treble level could have easily been fixed with a little twist of a knob or slider!
(ramblings of a pathetic senior)
I guess "hifi" enthusiasts started to hate PEQ somehow, this lead to "pure" sound ideal without any extra potentiometers etc. on the pathway to deteriorate sound and add noise? In my eyes this was the reason why so many people buy new speakers, amps, dacs and interconnects many times a year, to find the sound they like. When the bass or treble level could have easily been fixed with a little twist of a knob or slider!
(ramblings of a pathetic senior)
I also find those adjustments useful, though they are usually low quality and reliability. So I generally try to avoid it in my projects.
And to the second part of your post, I agree, most of audiophiles complaints and issues with certain loudspeakers could be solved just by simple resistor value change in crossover. But that is not as simple as it may seem, not mentioning nobody wants to dissect expensive commercial loudspeaker.
Today I spent several hours with tuning and listening. I did several small changes like woofer-midrange crossover from 330 -> 300 Hz, Alumens for tweeter, mild changes of tweeter and midrange levels, and overall sound started to make sense which means I started to really like it.
Very good technical performance ! When you fine tune, do you focus on changing resistance values, or do you also alter capacitors and coils?
What program material do you use for fine tuning?
j.
What program material do you use for fine tuning?
j.
hifijim, the tuning is sometimes more difficult than just resistor change, so I created image below to show what frequency range was addressed by certain crossover components.
My CD #1 for evalution is:
STS Dynamic experience #2, 2-3 songs from this CD (tracks 1, 2, 12 especially) and I have very good view on sound performance
Other CDs and SACDs....my goal is to make loudspeaker that plays all genres well with no apparent weakneses, so I have variety of CDs. Some are not perfectly audiophile, Dead can dance for example, the bass is overall to heavy, slow and emphasized, but I use it to listen how loudspeaker copes with that :
Hans Theessink - Blue grooves from Vienna, A 50th Anniversary celebration
Chris Jones - Slow roll
Dead can dance - Anastasis
Avishai Cohen - Continuo
Gogo Penguin - Humdrum star
Depeche mode - Violator
Leonard Cohen - You want it darker, Nevermind
Yello - Essential
Chris Jones - Roadhouses and Automobiles
Sheffiled Lab - Drum & track disc
Vivaldi SACD Esoteric, Le Quattro Stagioni
My CD #1 for evalution is:
STS Dynamic experience #2, 2-3 songs from this CD (tracks 1, 2, 12 especially) and I have very good view on sound performance
Other CDs and SACDs....my goal is to make loudspeaker that plays all genres well with no apparent weakneses, so I have variety of CDs. Some are not perfectly audiophile, Dead can dance for example, the bass is overall to heavy, slow and emphasized, but I use it to listen how loudspeaker copes with that :
Hans Theessink - Blue grooves from Vienna, A 50th Anniversary celebration
Chris Jones - Slow roll
Dead can dance - Anastasis
Avishai Cohen - Continuo
Gogo Penguin - Humdrum star
Depeche mode - Violator
Leonard Cohen - You want it darker, Nevermind
Yello - Essential
Chris Jones - Roadhouses and Automobiles
Sheffiled Lab - Drum & track disc
Vivaldi SACD Esoteric, Le Quattro Stagioni
Bozzio Levin Stevens - Black Light Syndrome
Marianne Thorsen, Trondheimsolistene - Mozart - Violin Concertos
Hi Petr,
Really impressed by your latest results ! and in particular the vertical polar plot in regards to the type of crossover (acoustic LR4)
Also as you have found yourself, you will have to slightly lower the cut-off freq of the TX versus the papyrus version.
Really impressed by your latest results ! and in particular the vertical polar plot in regards to the type of crossover (acoustic LR4)
Also as you have found yourself, you will have to slightly lower the cut-off freq of the TX versus the papyrus version.
jcga, thank you.....I just recalled you mentioned, earlier, that you preferred T34B over T25B, and for now I see it the same, comparing T25B in WG and T34B in WG. I used them both in different implementations though so it is not quite fair comparison.
Yesterday I spend a couple of hours with the tuning, and after experience with 32W in closed box I have to say it is not easy to make good sounding BR bass. 32W in closed box sounded after some burn in just right, but BR alignment takes time and work to even come close to 32W in closed box....
Yesterday I spend a couple of hours with the tuning, and after experience with 32W in closed box I have to say it is not easy to make good sounding BR bass. 32W in closed box sounded after some burn in just right, but BR alignment takes time and work to even come close to 32W in closed box....
yes going from 12” woofers back to 8” woofers takes some adjustment. It doesn’t matter what the static numbers stay.
a Sealed box is forgiving of mistakes to tuning, and IMO because the room gain more closely approximates the inverse of the 12dB/octave roll off of a sealed box it’s hard to go terribly wrong and have that “one note bass” from a misalignment.
For BR I think you have to forget about the theoretical (and anechoic) bass tunings
eg. Maximally flat, QB3, BB4 etc.
IME Bass tuning and the room size/placement go hand in hand. You cannot have one without the other.
So for the 22W/4851 have you considered a larger box and lower alignment than the maximally flat tuning?
eg. >28L; Fb <32Hz
I find that a gentle taper from 100Hz down to 50Hz matches the room better. So you align it so it simulates a sealed box rolloff until all but below the tuning frequency.
a Sealed box is forgiving of mistakes to tuning, and IMO because the room gain more closely approximates the inverse of the 12dB/octave roll off of a sealed box it’s hard to go terribly wrong and have that “one note bass” from a misalignment.
For BR I think you have to forget about the theoretical (and anechoic) bass tunings
eg. Maximally flat, QB3, BB4 etc.
IME Bass tuning and the room size/placement go hand in hand. You cannot have one without the other.
So for the 22W/4851 have you considered a larger box and lower alignment than the maximally flat tuning?
eg. >28L; Fb <32Hz
I find that a gentle taper from 100Hz down to 50Hz matches the room better. So you align it so it simulates a sealed box rolloff until all but below the tuning frequency.
Last edited:
Not yet, though I studied troelses arcticle etc. I think I will experiment with it later....
tktran: I agree on all points. I do not follow any theoretical bass alignment, I just model and try to find the tuning providing good bass extension, reasonable volume (I do not like large boxes) and most important the gradual rolloff starting ~100Hz (no sharp knees or overshoots) similar to closed box modelling.
I have 22W in 33l volume tuned to ~32Hz. I started with 36Hz tuning (which provides ~flat tuning) and this is too boomy, I knew I would need to lower the tuning, because I never got good bas from maximally flat tuning. Unfortunatelly I cannot make the port longer, so I used felt ring inserts and this worked for me already several times in previous projects.
I have 22W in 33l volume tuned to ~32Hz. I started with 36Hz tuning (which provides ~flat tuning) and this is too boomy, I knew I would need to lower the tuning, because I never got good bas from maximally flat tuning. Unfortunatelly I cannot make the port longer, so I used felt ring inserts and this worked for me already several times in previous projects.
Last edited:
Some of us seem to be more sensitive to certain aspects of bass performance. I have unfortunately found that I am rarely satisfied with bass reflex or passive radiator designs, and if the tuning frequency is above 30 Hz, then I would say I am never satisfied. Whereas with sealed box designs, I am almost always happy.
My experience with dipole bass systems is too limited to draw a conclusion, but the few I have heard sound very good in the upper bass, but lack authority and power in the deep bass below 40 Hz. I would like to listen to to a really good full range dipole some day.
Obviously most other serious listeners are able to find joy in a good BR speaker, as evidenced by the many examples. Almost all of the good studio monitors and serious high end hi-fi speakers are bass reflex, and this tells us something... It tells me that whatever I am hearing in the bass range, it is not a common thing. Therefore I would never claim that the sealed box design is superior to other designs, but simply that a sealed box is what I prefer.
Pida, you may be in a similar situation. Perhaps you can tune the box and tune the damping until you find joy. But it is also possible your best efforts will fall short of the big 32W in the big sealed box. Let's hope for the best for now...
j.
My experience with dipole bass systems is too limited to draw a conclusion, but the few I have heard sound very good in the upper bass, but lack authority and power in the deep bass below 40 Hz. I would like to listen to to a really good full range dipole some day.
Obviously most other serious listeners are able to find joy in a good BR speaker, as evidenced by the many examples. Almost all of the good studio monitors and serious high end hi-fi speakers are bass reflex, and this tells us something... It tells me that whatever I am hearing in the bass range, it is not a common thing. Therefore I would never claim that the sealed box design is superior to other designs, but simply that a sealed box is what I prefer.
Pida, you may be in a similar situation. Perhaps you can tune the box and tune the damping until you find joy. But it is also possible your best efforts will fall short of the big 32W in the big sealed box. Let's hope for the best for now...
j.
I will try it in week or two I think. I have some suitable material available for that, it is Basotect, it is easy to cut membranes with different thicknesses and put it in port.
I have same observation regarding tuning frequency. I listened to 32W with 2x12"PRs tuned to 19Hz, and bass quality was very close to closed box. I think that tunings above 30Hz are in the range of typical room modes and there is coupling of port and room modes.
Most of commercial speakers are BR, but from hifi friends around I also know how many problems they have with their loudspeakers and systems. In that regard closed boxes are more easy to get sounding right in various rooms.
For now, my efforts with 22W bass sound improvements seem to go the right direction, and let's not forget the woofer still needs some burn in.
Something to consider from https://www.audiosciencereview.com/forum/index.php?threads/analytical-analysis-room-gain.23211/
"We need to consider the roll-off of a speaker. A closed sub will roll-off in a second order manner, so that the pressure response resembles that of a second-order high-pass function. And a ported speaker will roll-off with a fourth-order response. So if we assume that we have a closed sub in a corner, and assume that it behaves as a second-order high pass filter with a cut-off frequency of 35 Hz (I think the Linkwitz Thor has this without the external filter applied; I had that setup once and it was so nice), we finally get this result:
Wow... We have a flat in room response for a sub with finite bandwidth. Why is that? Well, we have actually forgotten one thing; the indices (nx,ny,nz) do not start at (1,0,0), (0,1,0), or (0,0,1); they start at (0,0,0)! We have a mode at 0 Hz that pressurizes the room the same in all positions, so no gradients, and it satisfies the wave equation as discussed already. Room gain is simply the effect of having an eigenmode at DC! With the increase in resulting pressure as the excitation frequency gets closer and closer to the modal frequency being second-order (see the denominator in the equation higher up), and the output from a closed sub goes down by an order of two, we can get a resulting pressure which is flat towards DC. So while we do not have sound at 0 Hz, since there are no oscillations, the effect of any mode extends away from it. Also, for a ported subwoofer we will not be able to have this flat response, because of its higher order roll-off, but the in room response will still be modified by the mode."
Sealed bass lover here too! Room gain is substantial with large woofers with low Fs. Gain helps with spl, but I think the best feature of sealed bass is lower excess group delay, which gives better "attack" of bass transients. It is surprisingly important also for classical music, but not much with movie effects. BR port signal is one cycle late at max spl, like having LR4 xo.
Here is an article about room gain with sealed bass. Very much room and location related
https://data-bass.com/#/articles/5cb5fb285389a80004c7e58a?_k=ic1stu
Here is an article about room gain with sealed bass. Very much room and location related
https://data-bass.com/#/articles/5cb5fb285389a80004c7e58a?_k=ic1stu
I also think it is not only about frequency response shape but also excess group delay. 32W closed box had certain sound qualities similar to bass from headphones.