I get new case mainly done and made first measurements.
Simulation with adjusted Ql to fit cone nearfiled measurement shape is this.
Case is from 18 mm oak panel. I probably not install speaker grills.
Simulation with adjusted Ql to fit cone nearfiled measurement shape is this.
Case is from 18 mm oak panel. I probably not install speaker grills.
When listening the result, it is clearly understandable that bass is OK, I not expect more from this small speaker.
But problem is in range 1-5 kHz what have too high level and fall from 6 kHz to 20 kHz.
If I compare Alpair5.3 measurements in micro stereo (black line) and in test box (green line) there are significant difference as on image below.
Test box measurement is made with flat amplifier, box have about same front panel size, but not have 20 mm plastic front panel what forms basically wave guide.
How is possible to cure this wave guide effect not removing the plastic front panel?
But problem is in range 1-5 kHz what have too high level and fall from 6 kHz to 20 kHz.
If I compare Alpair5.3 measurements in micro stereo (black line) and in test box (green line) there are significant difference as on image below.
Test box measurement is made with flat amplifier, box have about same front panel size, but not have 20 mm plastic front panel what forms basically wave guide.
How is possible to cure this wave guide effect not removing the plastic front panel?
To better and more precisely illustrate the problem I made one more image, compensated speaker response in micro stereo with its amplifier response to get directly comparable response with test box and flat amplifier measurement.
If I make FR holes frequencies wave length calculations, then 6,3 kHz is 54 mm what is about diameter of hole in plastic frame the speaker and 12,5 kHz half of that length.
Very much like comb filter.
If I look on impulse response, there is nothing good. Sound travel time of 54 mm is 158 us.
Very much like comb filter.
If I look on impulse response, there is nothing good. Sound travel time of 54 mm is 158 us.
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Hi, give a chance to those speakers to find a home. I bet that the old cabinet as it appears in post #19 can be used for making two cabinets
Can somebody really be interested in cabinet from 9 mm (very) low quality MDF?
But to the topic.
For comparison same Alpair 5.3 impulse response in test box, there seems all nearly OK.
But to the topic.
For comparison same Alpair 5.3 impulse response in test box, there seems all nearly OK.
Is possible to 3D print replacement for front panel ring around the speakers what will absorb higher than 5 kHz sound or 6,3 and 12,6 kHz? Some kind of meta material like ring?
Will it be difficult and is total overkill or it can be done as DIY?
If you can find some (2mm) lead sheet, you're done. Some stuffing on the inside and you get two soundproof cabinets with flat baffle.
I advise to mount the driver normally, without any recess, so it protrudes rather than being recessed.
This, together with the two distinct cabinets and sound sources, would let you put in a position for well listening to the 'new' system, or whatever you use to power them