amplifier using LM1875 for mid's and High's ... Where the woofers were powered using 4 channel car amplifier ... bridged channel 1 + 2 and 3+4 respectively
There is another 12inch DIY subwoofer yet to be placed into this room and it is powered by TDA8950 Class D amplifier module
There is another 12inch DIY subwoofer yet to be placed into this room and it is powered by TDA8950 Class D amplifier module
Ok, i know the situation about income too...
I asked because it could have been of help to identify absolute polarity of your woofer and mid ( and tweeter too).
All is not lost for the woofer and mid though: you can use a 9v battery to check if they are (both pair) wired accordingly.
You connect + side of battery to the red ( or + identified terminal) on each driver and check the membrane is pushing to the outside ( once you close the circuit connecting the - at your battery).
DON'T DO IT WITH YOUR TWEETER! Or it will go to tweeter heaven.
This way you could be sure of 2/3 of loudspeaker are wired as they should.
To identify the tweeter you could try a null test: send a sine( whose freq is the same that crossover point between mid and tweet but with no filter engaged, both should run fullrange so be carefull not to send dc to your tweeter!) to both tweet and mid. Try to have approximately the same spl from the mid and tweeter using a basic spl meter ( an app on your smartphone should be more than enough for this and use volume control on each amp to perform the task) then you switch opposite polarity of tweeter ( once you have identified correct absolute polarity of mid of course).
If the tweeter was wired correctly you should experience a loss of overall spl. If you experience the inverse then your absolute polarity is wrong.
The loss should be audible ( and easier to identify than gain ime) but keep in mind it won't be total null, other parameters come into play with this ( center to center spacing comes to mind).
That said it should do the trick.
Once done you identify the terminal as + or - and you should never be bothered to open the speaker again to check physical wiring scheme.
Ok so you are active tri amped. What do you use for filtering? Dsp? Which one ( software, hardware,...).
I asked because it could have been of help to identify absolute polarity of your woofer and mid ( and tweeter too).
All is not lost for the woofer and mid though: you can use a 9v battery to check if they are (both pair) wired accordingly.
You connect + side of battery to the red ( or + identified terminal) on each driver and check the membrane is pushing to the outside ( once you close the circuit connecting the - at your battery).
DON'T DO IT WITH YOUR TWEETER! Or it will go to tweeter heaven.
This way you could be sure of 2/3 of loudspeaker are wired as they should.
To identify the tweeter you could try a null test: send a sine( whose freq is the same that crossover point between mid and tweet but with no filter engaged, both should run fullrange so be carefull not to send dc to your tweeter!) to both tweet and mid. Try to have approximately the same spl from the mid and tweeter using a basic spl meter ( an app on your smartphone should be more than enough for this and use volume control on each amp to perform the task) then you switch opposite polarity of tweeter ( once you have identified correct absolute polarity of mid of course).
If the tweeter was wired correctly you should experience a loss of overall spl. If you experience the inverse then your absolute polarity is wrong.
The loss should be audible ( and easier to identify than gain ime) but keep in mind it won't be total null, other parameters come into play with this ( center to center spacing comes to mind).
That said it should do the trick.
Once done you identify the terminal as + or - and you should never be bothered to open the speaker again to check physical wiring scheme.
Ok so you are active tri amped. What do you use for filtering? Dsp? Which one ( software, hardware,...).
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More insight about a 'nulling' process explained:
https://www.diyaudio.com/forums/mul...rained-layer-construction-14.html#post3231402
https://www.diyaudio.com/forums/mul...rained-layer-construction-15.html#post3231567
But there is a difference in Bon's procedure: as one of his target is time aligned speakers he does engage xover filters in the null test. This can be done because he have a target ( time aligned at listening position), have already defined filter type (bessel type for their transient behavior as the cleanest transient responce is one of his goal too) and measurement gear.
In your case you 'just' check for polarity, you not nescessarely need same accuracy.
https://www.diyaudio.com/forums/mul...rained-layer-construction-14.html#post3231402
https://www.diyaudio.com/forums/mul...rained-layer-construction-15.html#post3231567
But there is a difference in Bon's procedure: as one of his target is time aligned speakers he does engage xover filters in the null test. This can be done because he have a target ( time aligned at listening position), have already defined filter type (bessel type for their transient behavior as the cleanest transient responce is one of his goal too) and measurement gear.
In your case you 'just' check for polarity, you not nescessarely need same accuracy.
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