Greetings fellow diyers.
I´ve inherited a pair or tower speakers from my grandpa.
As you can see, big speakers.. 10 inch woofers, 4 feet tall.
Now look at this.. I´ve been measuring frequecy sweeps with my phone from the listening position. Very little output in the sub bass range.
This is the woofer crossover, I noticed a few caps in series which to my understaning are used to attenuate bass frequencies.
Tweeter and Midrange crossover
My setup: Room is 22x14x8. Big opening on the left side (I live in a loft). Long wall placement.
My grandpa had a passive subwoofer in his system also which makes my suspicious.
Looking at the woofer specs (Peerless 831727) and cabinet size I should be getting flat response to 35 hz with ease! Why am I getting so little bass? Can anyone tell me what´s going on here? Please help!! 😛
I´ve inherited a pair or tower speakers from my grandpa.
As you can see, big speakers.. 10 inch woofers, 4 feet tall.
Now look at this.. I´ve been measuring frequecy sweeps with my phone from the listening position. Very little output in the sub bass range.
This is the woofer crossover, I noticed a few caps in series which to my understaning are used to attenuate bass frequencies.
Tweeter and Midrange crossover
My setup: Room is 22x14x8. Big opening on the left side (I live in a loft). Long wall placement.
My grandpa had a passive subwoofer in his system also which makes my suspicious.
Looking at the woofer specs (Peerless 831727) and cabinet size I should be getting flat response to 35 hz with ease! Why am I getting so little bass? Can anyone tell me what´s going on here? Please help!! 😛
Really hard to measure bass in a room. A nearfield (very close [cms]) from the woofer are more useful. Down there room dominates. Room placement, and moving your measuring device around will help get a better idea.
But if there is a BIG series cap on the woofers, that would be for a roll-off in the bass — sealed? then a 3rd order bass alignment. They could well have drifted. TRy shorting them out and see/hear what happens.
But if there is a BIG series cap on the woofers, that would be for a roll-off in the bass — sealed? then a 3rd order bass alignment. They could well have drifted. TRy shorting them out and see/hear what happens.
My first question was going to be "How sure are you of your phone?". But of course if you don't hear the bass, it's probably not there.
As Dave says, go in close with the phone and check each woofer. That might tell is something. Are they all working and working the same?
As Dave says, go in close with the phone and check each woofer. That might tell is something. Are they all working and working the same?
Are you sure they are not in parallel with each other (and the woofer) instead?
This is much more likely.
I'm not familiar with your graphing software. What is the difference between the red and yellow traces? The yellow trace looks like solid extension to 30hz which seems reasonable for a pair of 10s, and equal to the level around 1khz. The red trace looks much weaker.
Are those replacement woofers? Going by screw holes and not knowing the history.. the woofers ts parameters could be way off originals ?
With those two 10" Peerless woofers, bass shouldn't be a problem. There's something else going on. My guess is the woofers aren't connected in the proper phase so they're cancelling each other out.
... or one of them is a passive radiator and not a woofer.
Remove the cap and play some tunes to find out if the cap is affecting the bass response.
Remove the cap and play some tunes to find out if the cap is affecting the bass response.
I´m using a phone app called Spectroid, the yellow line is ambient noise, the red one is the speakers response. Very weak indeed 🙁
All 4 woofers are working and working the same yes. The bass is definitely not there. I can´t hear anything below 70-80hz
Uhm yes, you are probably right. By series I meant before reaching the woofer. I´m sorry, I don´t understand half of what I´m looking at hehe! I´m kind of a newbie regarding crossovers.
Did you do the "battery polarity test"? Just take a "AA" battery, (1.2-1.5V) across the terminals...making sure both drivers are running the same direction???
Silly as it sounds, a surefire & harmless way to confirm polarity.
---------------------------------------------------------------------------Rick........
Silly as it sounds, a surefire & harmless way to confirm polarity.
---------------------------------------------------------------------------Rick........
But how could it possibly cancel from 30hz to 80hz? What I find suspicious is that 80hz crossover frequency cutoff which is very common when you want to add a subwoofer. On the other hand, why make an 80hz crossover frequency cutoff with such speakers. They should be more than capable of reaching low bass by themselves. 😕
(1) Have you tested the woofers? try a 9V battery (woofer only)-you can touch it momentarily.
YouTube
(2) Check for broken wires, make sure you have good connection to the binding posts.
(3) Check for any broken component leads on the woofer x-over board.
Check for any burnt components.
--
I had a Polk Center channel that had a power resistor that came loose - one side had come free of the solder on the cct board.
I resoldered the loose lead & that fixed it.
YouTube
(2) Check for broken wires, make sure you have good connection to the binding posts.
(3) Check for any broken component leads on the woofer x-over board.
Check for any burnt components.
--
I had a Polk Center channel that had a power resistor that came loose - one side had come free of the solder on the cct board.
I resoldered the loose lead & that fixed it.
On the "why 80Hz", possibly for no other reason that it is "convention"....
One test I would do would be to simply, disconnect the woofers from the crossover and wire the them direct to the terminals on the back (ensuring to connect same as to crossover, ie series or parallel as appropriate) and run them full range and do a measurement. That eliminates the crossover from the eqaution and should show you what their actual response in the box is. Then you can go from there.
Tony.
One test I would do would be to simply, disconnect the woofers from the crossover and wire the them direct to the terminals on the back (ensuring to connect same as to crossover, ie series or parallel as appropriate) and run them full range and do a measurement. That eliminates the crossover from the eqaution and should show you what their actual response in the box is. Then you can go from there.
Tony.
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Woofers are working correctly. I´ve been listening to music with these for a few months already, I can hear low bass but it´s low in output.
All wires and connections are rock solid, nothing is loose, this speakers are built like a tank 🙄
Also no burnt components nor broken component leads. Everything looks fine but will check again just in case.
It could be your expectations. A truly good speaker does not have any bass output at all,
until the music calls for it. Of course, the room and other factors can affect the bass as well.
What other equipment is being used, and which speakers are you used to hearing?
It's unlikely there is anything wrong with the speakers as shown that would affect the low bass.
Are both speaker systems wired in the same polarity ("in phase")? Check both ends of each of the wires.
Place the speakers nearly face to face and reverse one of the wire ends, does the bass output cancel?
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Assuming the little mic in my 2011 MacBook Air resembles the mic in your cellphone, here's the answer in post 1, figure 3:
You can use your laptop mic - diyAudio
Your mic is likely not responding as you go below 60 Hz relative to mid-band.
Based on 60 years experience, unless you play pop recordings (that have exaggerated bass) and play them pretty loud, the bass has to be well louder than flat to sound satisfyingly realistic.
B.
You can use your laptop mic - diyAudio
Your mic is likely not responding as you go below 60 Hz relative to mid-band.
Based on 60 years experience, unless you play pop recordings (that have exaggerated bass) and play them pretty loud, the bass has to be well louder than flat to sound satisfyingly realistic.
B.
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This is my first set of good quality speakers.. At 20-80 hz the woofers are definitely moving, they move a LOT, in fact, things around the house start to resonate and rattle but I hear very little sound. Amplifiier is Nad 316bee.
Regarding speaker polarity, i made sure everything is wired correctly but i will try the face to face cancellation experiment, thanks
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