SEAS U22REX/P-SL measurements

It is H2 peak 600-800Hz. It did not worry me before, and worries me even less after 3days of listening to them. No driver is ideal, I always try not to chase and be worried by every tiny detail, but rather to see overall picture and most importantly to judge how the things sound.

Not saying details don't matter, it is just that in audio we swap one bad with another bad. Nothing is ideal. My view on this H2 peak is following...there is not associated distortion peaks of H3-H4-H5. Frequency response is reasonably linear. There is not much one can do to get rid off this peak except cone edge treatment. I assume general consensus is that H2 adds some softness, veils the things. So far I did not detect any softness or anything negative that I could attribute to this H2 peak, and actually I did not detect anything I would not like when listening to this driver. Bass is well defined, no slow and muddy sound, midrange has clarity. Its sound is open. For example, compared to 18W revelators or classics, they all have elevated H2 in the midrange and yes they have more softer midrange, less clear open and articulate.

Of course these are all impressions after 3days listening, it always take some time to get familiar with the sound of the new drivers, let them burn in, do more listening sessions and recognize the issues and or just make fine tuning of the crossover.
 
People generally underestimate the influence of early reflection on the perception of sound! (masking etc)

Record the sound of speaker in question in your room/listening position and record also same speaker/output level outdoors! (same distance/orientation to speaker)

Now you have a glimpse of how strong reflections colour the sound and masking parts of it .

Luckily situation is better with 2 ears plus brain analyser (HRTF etc) instead of single dumb microphone ...

Outdoor listening gains cab related problems and driver distortion , nearfield prpbably even more so!

Audio survival is tough , only the ... :)
 
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It is H2 peak 600-800Hz. It did not worry me before, and worries me even less after 3days of listening to them. No driver is ideal, I always try not to chase and be worried by every tiny detail, but rather to see overall picture and most importantly to judge how the things sound.

Not saying details don't matter, it is just that in audio we swap one bad with another bad. Nothing is ideal. My view on this H2 peak is following...there is not associated distortion peaks of H3-H4-H5. Frequency response is reasonably linear. There is not much one can do to get rid off this peak except cone edge treatment. I assume general consensus is that H2 adds some softness, veils the things. So far I did not detect any softness or anything negative that I could attribute to this H2 peak, and actually I did not detect anything I would not like when listening to this driver. Bass is well defined, no slow and muddy sound, midrange has clarity. Its sound is open. For example, compared to 18W revelators or classics, they all have elevated H2 in the midrange and yes they have more softer midrange, less clear open and articulate.

Of course these are all impressions after 3days listening, it always take some time to get familiar with the sound of the new drivers, let them burn in, do more listening sessions and recognize the issues and or just make fine tuning of the crossover.
The U22 seems to be a "fast" driver in this configuration, not goes low 50Hz and low displacement of the cone below 100Hz due to the helmholtz resonator. It should a very balanced speaker, not too much bass, to keep the midrange clear.
Do you think the driver is close to excel driver, if you know them ? What I like with the excel sound, it is very close to reality with low coloration.
 
jerome69: yes, the listening impressions confirm what you described. Unfortunately I do not have any experience with Excell drivers. I simmed the bass alignment with W22NX003, you have previous version of this driver. It has ~1dB lower sensitivity and same volume it goes little lower. Sound character could be quite similar.

Did you see Lotus RW 220? Models well in ~33l BR, it is 4ohm and system sensitivity would be ~88dB, copper rings, low Le, price is below Excel drivers.
https://www.seas.no/index.php?optio...e&id=135:rw-220-l0022-04s&catid=63&Itemid=252
 
daanve: I thought of that low Qms as well when I was ordering U22, it is specified Qms = 1.77. To my ears this driver sounds open, palpable, "fast" and I do not percieve the lack of dynamics at lower listening levels. Another case of low Qms drivers I liked is Dayton RS150-4 and RS150-8 with Qms 1.96 and 1.66. So from my experience I cannot reliably attribute low dynamics to low Qms.
For me low dynamics at lower listening levels means the sound loses the open character, details get veiled and hidden, the sound gets boring and the bass loses the grip.
 
Qms also includes damping losses of eddy currents in the voice coil former. E.g. Seas and Dayton use Aluminum formers, and and as Aluminum is a very good conductor the losses are high and correspondingly Qms is low.

In comparison to "pure" mechanical losses (e.g. of the surround or suspension, that are highly nonlinear) the voice coil eddy current losses are pretty linear and give neglectable contribution to distortions. On the one hand there is better cooling of the voice coil as Aluminum is also a very good heat conductor, on the other hand you lose 1-2 dB around the resonance frequency in comparison to a non-conductive material voice coil former.
 
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No.
There is no equivalent in the TSPs for the eddy current losses, but they act like mechanical damping and cannot be distinguished from it with the usual added mass or added volume TSP measurement techniques.

Qes = 2pi*Fs*Mmms * Rdc/Bl^2 only consideres the force factor and Rdc on the electrical side. Both are not affected by eddy current losses.
 
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jerome69: yes, the listening impressions confirm what you described. Unfortunately I do not have any experience with Excell drivers. I simmed the bass alignment with W22NX003, you have previous version of this driver. It has ~1dB lower sensitivity and same volume it goes little lower. Sound character could be quite similar.

Did you see Lotus RW 220? Models well in ~33l BR, it is 4ohm and system sensitivity would be ~88dB, copper rings, low Le, price is below Excel drivers.
https://www.seas.no/index.php?optio...e&id=135:rw-220-l0022-04s&catid=63&Itemid=252
The W22NY003 is a driver with a little different motor to the W22NY001, I have the W18NX001 (different to the magnesium W22NX001 I have too). Perhaps Purifi drivers force SEAS to improve their drivers ?
Note I am a little picky on sound driver, I don't like plastic cone in general, I prefer paper and magnesium cone. But I didn't like the T18REX/XFC till I listen to it in a very neutral box with sand and I heard an other speaker with a very good sound, very precise and clear. Sometimes I wonder if I really listen to a driver not to otherthings like box panel radiations.

Yes I see the RW220, but I don't like SEAS Alu cone driver in the midrange, they are very good driver in the bass but in the midrange they miss precision, naturalness to my ears. In a three way the RW220 below 200Hz could be a good bass-low mid driver in a small box. But I like a lot the SEAS aluminium/magnesium alloy tweeter dome. Never listen to the aluminium/magnesium alloy cone like the W26FX and the C18NE.

I meant W22NY003.

I have U22 in 37l so if I decide to make new cabs I will go with ~45l which adds ~2dB at 30Hz.
Yes SEAS 8" drivers seems work well in the volume 40/50L :) What I experiment with different SEAS 8", pay attention to the frequency tuning, I notice too low tuning make a subjective slow speaker, not very vivid sound.
 
daanve: I thought of that low Qms as well when I was ordering U22, it is specified Qms = 1.77. To my ears this driver sounds open, palpable, "fast" and I do not percieve the lack of dynamics at lower listening levels. Another case of low Qms drivers I liked is Dayton RS150-4 and RS150-8 with Qms 1.96 and 1.66. So from my experience I cannot reliably attribute low dynamics to low Qms.
For me low dynamics at lower listening levels means the sound loses the open character, details get veiled and hidden, the sound gets boring and the bass loses the grip.
How about Dayton Audio RS225-8 8" alu? Have you tested that driver?
 
What I experiment with different SEAS 8", pay attention to the frequency tuning, I notice too low tuning make a subjective slow speaker, not very vivid sound.
Definitely agree. And I do not like maximally flat, sharp knee either, I tune little bit lower, to my ears this sounds better and works better in the most of the rooms. Anyway, values from woofer alignment modelling sw are just initial and it is needed to confirm it with the impedance sweep and listening. I usually try 2-3 port lengths and few changes of the amount of dampening material in the cabs. I also observe group delay.