To the speaker Wizards,
First of all im not sure if this is the right forum. Let me know. Second the speakers in question might not be familiar. Still im curious about your thoughts.
Recently aquired Impulse 74 transmission-line speakers which are rated at 8 ohm, 91dB, 25Hz to 25kHz.
Expecting them to deliver tons of bass for my electronic music.
They replace the MB Quart 600
Rated at 4 ohm, 90dB, 35Hz to 31kHz.
Surprisingly the Impulse delivers much less bass to my listening spot! It sounds much more clear and open, far surpassing the Quart's soundstage. Though the lack of bass leaves me somewhat unsatisfied.
Could this be due to woofer positioning and room acoustics?
The impulse is much taller and has the woofer about 50cm higher above the ground. Both are front ported two-way designs build in 1992. The impulse now stand in the same spot where the Quarts used to be.
Im hoping there is a possible explanation that could lead me to a fix or help me descide wether to keep or resell the impulse 74.
Much thanks and cheers,
Ruben
(The impulse making the quart look small)
First of all im not sure if this is the right forum. Let me know. Second the speakers in question might not be familiar. Still im curious about your thoughts.
Recently aquired Impulse 74 transmission-line speakers which are rated at 8 ohm, 91dB, 25Hz to 25kHz.
Expecting them to deliver tons of bass for my electronic music.
They replace the MB Quart 600
Rated at 4 ohm, 90dB, 35Hz to 31kHz.
Surprisingly the Impulse delivers much less bass to my listening spot! It sounds much more clear and open, far surpassing the Quart's soundstage. Though the lack of bass leaves me somewhat unsatisfied.
Could this be due to woofer positioning and room acoustics?
The impulse is much taller and has the woofer about 50cm higher above the ground. Both are front ported two-way designs build in 1992. The impulse now stand in the same spot where the Quarts used to be.
Im hoping there is a possible explanation that could lead me to a fix or help me descide wether to keep or resell the impulse 74.
Much thanks and cheers,
Ruben
(The impulse making the quart look small)
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Different manufacturers can rate their speakers under different conditions. The fine print often says the frequency limits are at 10 dB down. In-room low-end response will vary wildly according to room volume and speaker location.
Transmission line speakers are on rather shaky theoretical ground, I think. They might be improved by blocking the port.
Transmission line speakers are on rather shaky theoretical ground, I think. They might be improved by blocking the port.
Electronic music.
Just use a sub. any powered 12" will wake up a mix.
Far as keeping them. If clarity is good might be worth it.
Far as a system. I dont care to put small midrange
speakers in a some magic port box.
just use a midrange for midrange and a sub for sub.
improving bass for now, can be up against a wall, or corner loading
basically set up in a corner.
Just use a sub. any powered 12" will wake up a mix.
Far as keeping them. If clarity is good might be worth it.
Far as a system. I dont care to put small midrange
speakers in a some magic port box.
just use a midrange for midrange and a sub for sub.
improving bass for now, can be up against a wall, or corner loading
basically set up in a corner.
I thank you for sharing your thoughts.
Not sure why i did not get any notifications of this thread. I assumed it was a shot in the dark.
It is most likely that the speakers are specced with different stardards. The 74 being specced with 'Frequentie Bereik' which translates to F range but is interchangable with F response in Dutch.... And who knows whether they used -3, -6 or -10dB points..nowhere to be found.
I started playing with an old Quad 33 pre to use its bass boost. That definately got me the rumble I was looking for. Back to the level where it was with the MB Quarts untill my housemate came knocking on the door. He said the whole place was shaking and came to see if I was ok.
This left me to conclude that the 74 definately produces the bass, just not on my listening spot. So I flipped the phase on one of the towers and lowend behold. The couch was shaking again, only without my housemates thinking theres an earthquake going on.
Im left to conclude that the speakers height and overall size moved the dips and bumps in bass response to different spots in my room. Its always fun to move around and listen to the long wavelenghts interacting.
Flipping the phase does cause the sound to extend beyond the speakers left and right a bit less often I feel. Though this is hard to judge as it still happens and the spatial reproduction is still spectacular compared to the MB Quarts. When critically listening for soundstage width it always appears more narrow to me both in or out of phase.
Ive been hapily listening ever after.
Much cheers,
Ruben
Not sure why i did not get any notifications of this thread. I assumed it was a shot in the dark.
It is most likely that the speakers are specced with different stardards. The 74 being specced with 'Frequentie Bereik' which translates to F range but is interchangable with F response in Dutch.... And who knows whether they used -3, -6 or -10dB points..nowhere to be found.
I started playing with an old Quad 33 pre to use its bass boost. That definately got me the rumble I was looking for. Back to the level where it was with the MB Quarts untill my housemate came knocking on the door. He said the whole place was shaking and came to see if I was ok.
This left me to conclude that the 74 definately produces the bass, just not on my listening spot. So I flipped the phase on one of the towers and lowend behold. The couch was shaking again, only without my housemates thinking theres an earthquake going on.
Im left to conclude that the speakers height and overall size moved the dips and bumps in bass response to different spots in my room. Its always fun to move around and listen to the long wavelenghts interacting.
Flipping the phase does cause the sound to extend beyond the speakers left and right a bit less often I feel. Though this is hard to judge as it still happens and the spatial reproduction is still spectacular compared to the MB Quarts. When critically listening for soundstage width it always appears more narrow to me both in or out of phase.
Ive been hapily listening ever after.
Much cheers,
Ruben
Far as keeping them. If clarity is good might be worth it.
Far as a system. I dont care to put small midrange
speakers in a some magic port box.
Far as a system. I dont care to put small midrange
speakers in a some magic port box.
Check you did not turn the phase on one speaker ie plus and minus.
Check with 1.5 volt battery if the bass drivers have correct polarity ie the same one if plus minus are all correct.
It happened to me buying a used speaker that the predecessor made a fault and wired one bass wrong.
Or both bass drivers being out of phase with the middle tone driver giving suckout at crossover frequency.
Check with 1.5 volt battery if the bass drivers have correct polarity ie the same one if plus minus are all correct.
It happened to me buying a used speaker that the predecessor made a fault and wired one bass wrong.
Or both bass drivers being out of phase with the middle tone driver giving suckout at crossover frequency.
Good point. Ill try. Any way to verify the phase on the tweeters? The impuls are two ways bi wireable.
You can turn on both boxes plus and minus at the drivers, tweeter, mids, bass drivers and listen what sounds better. Or with Mono music one box unchanged versus the other with changed polarity.
Or you measure if you have measurement equipment
Or you measure if you have measurement equipment