I recently purchased a set of older Marshall speakers with blown tweeters. I could see the 15" woofer is 8ohm but I had to guess for the tweeter. I replaced the diaphragms in the tweeters with 8ohm as well and now that I can finally hear them running they are really bright. I would like to avoid just getting a l-pad to fix it as although they are not super expensive to buy neither were the speakers and if I can I would prefer to just do it with resistors. My question is, can I use REW to analyse it and figure out how many db I need to turn the tweeters down (and from there calculate my two resistors) to get a better sound?
Cheers!
P.S. I am quite new to this and have only just started playing around with REW.
Cheers!
P.S. I am quite new to this and have only just started playing around with REW.
I don't know about using REW for your purpose, but you can experiment by simply placing single resistors in series with the tweeter until you find the one that gives the wanted attenuation.
Then, by playing around with the calculator below, the single resistor (R) that gave the wanted attenuation may be substituted by the required L pad resistors (Rs and Rp).
L pad calculator - attenuation dB damping impedance decibel loudspeaker speaker voltage divider - sengpielaudio Sengpiel Berlin
Then, by playing around with the calculator below, the single resistor (R) that gave the wanted attenuation may be substituted by the required L pad resistors (Rs and Rp).
L pad calculator - attenuation dB damping impedance decibel loudspeaker speaker voltage divider - sengpielaudio Sengpiel Berlin
With the mention of the word 'Marshall', I'm guessing this is for bass guitar? - then you'll need to use high power resistors
Thanks for that, I have just sourced some suitable resistors and am going to give it a try 😀
I hope you've noted Pete's comment.
Low power resistors will suffice for experimental purposes, but the final L pad resistors should be of adequate power rating.
It depends on your amplifier power and the crossover frequency, but I would go for ceramic resistors of at least, say, 25W in your application.
Thanks for the reply, do let us know how you got on.
Low power resistors will suffice for experimental purposes, but the final L pad resistors should be of adequate power rating.
It depends on your amplifier power and the crossover frequency, but I would go for ceramic resistors of at least, say, 25W in your application.
Thanks for the reply, do let us know how you got on.
I think I'm in the same situation or at least maybe.
In my case though it's easier as I know the speakers sensitivity and the tweeter sensitivity so I need to lower around 3 DB, but I haven't assembled the tweeter as I received today and need to cut it or the original plastic fitting because it's smaller than the original plastic so will have to wait until I assemble to see if it's too bad (a bit bright would actually help for gaming, but too much I would have to reduce).
However I don't know which resistors to use because this is a pretty strange setup to me as I don't understand much of Hifi...
First the center speaker has 2 woofers: 8ohms 10W and they are connected in parallel which would be 4ohms however the actual whole speaker is 8 ohms and while reading with a multimeter the full assembled speaker it's above 7ohms and very close to 8ohms and strange is the bookshelf speakers only have 1 same exact woofer + same exact tweeter and it's also 8ohms and reads the same ohms on the multimeter which is super strange and the only electronics those speakers have is just a 2.2uF cap from - to - of the tweeter (unless tweeter in the central speaker is inverted because I don't even know which side on the tweeter is the + as the manufacturer doesn't even seem to be sure either lol, they have mistakenly marked both sides with a red permanent marker so 2 red sides lol), and the woofers are direct...
The tweeters are all the same in the bookshelf speakers and central speaker and they are 4 ohms 3W, so I don't even understand the maths of the central speaker with 2 same woofers no electronics and giving same total ohms as just 1 woofer in the bookshelf speakers😕 (I wonder what kind of witchcraft is in those bad speakers
) and I bet the tower speakers are exactly like the central speaker, but since they already have soft dome tweeters and sound miles better I won't even open them up.
In my case though it's easier as I know the speakers sensitivity and the tweeter sensitivity so I need to lower around 3 DB, but I haven't assembled the tweeter as I received today and need to cut it or the original plastic fitting because it's smaller than the original plastic so will have to wait until I assemble to see if it's too bad (a bit bright would actually help for gaming, but too much I would have to reduce).
However I don't know which resistors to use because this is a pretty strange setup to me as I don't understand much of Hifi...
First the center speaker has 2 woofers: 8ohms 10W and they are connected in parallel which would be 4ohms however the actual whole speaker is 8 ohms and while reading with a multimeter the full assembled speaker it's above 7ohms and very close to 8ohms and strange is the bookshelf speakers only have 1 same exact woofer + same exact tweeter and it's also 8ohms and reads the same ohms on the multimeter which is super strange and the only electronics those speakers have is just a 2.2uF cap from - to - of the tweeter (unless tweeter in the central speaker is inverted because I don't even know which side on the tweeter is the + as the manufacturer doesn't even seem to be sure either lol, they have mistakenly marked both sides with a red permanent marker so 2 red sides lol), and the woofers are direct...
The tweeters are all the same in the bookshelf speakers and central speaker and they are 4 ohms 3W, so I don't even understand the maths of the central speaker with 2 same woofers no electronics and giving same total ohms as just 1 woofer in the bookshelf speakers😕 (I wonder what kind of witchcraft is in those bad speakers
) and I bet the tower speakers are exactly like the central speaker, but since they already have soft dome tweeters and sound miles better I won't even open them up.
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