cheers system7. is it worth attenuating the tweeter down by modding the crossover to have the resistors? is it the diagram with the 2.2 and 15, and the 2.2ohm seems a bit rare? I could do the other but the 0.68uf cap's seem quite pricey once ive done 6.
any preference on the caps? low resistance tight tolerance?
p.s. does system7 refer to an old game publishing house?
any preference on the caps? low resistance tight tolerance?
p.s. does system7 refer to an old game publishing house?
ordered the electrolytics and poly's.
if I use the circuit you posted with the 2.2 and 15 will that bring the tweeter roughly back in line?
if I use the circuit you posted with the 2.2 and 15 will that bring the tweeter roughly back in line?
just had a thought. when im modding the pcb ill probably drill some holes in it to put the extra resistors in. is the pcb material safe? I know some old kit can contain some nasty stuff.
That's the rockwool used for acoustic function. It can flow in the air as particle and get inside lungs...but it also causes irritation to the skin ...so the eyes, nose, mouth.
do I wire the audax tweeter mod as per the diagram showing the 2.2 and 15 ohm resistors if I don't want to go down the zorbel route?
I have drilled thousands of holes in PCB boards. As long as you are not planning to eat the dust or rub it in to your eyes you should be fine!
cheers just wanted to be sure, as in the 70's they seemed to put asbestos and other **** into everything. my old house even had it in the artex.
anyway can anyone confirm the diagram with the 2.2 and 15 is the way to correct my audax's?
anyway can anyone confirm the diagram with the 2.2 and 15 is the way to correct my audax's?
Preferred Decade values are 1, 2.2, 4.7, 10 on the simplest scale.
More precise is 1, 1.5, 2.2, 3.3, 4.7, 6.8, 10.
2.2R plus 15R attenuator will give about 3db reduction in level. That is half the power. It's for you to judge with your replacement tweeter. I have no idea how your modified speaker sounds, but bright at the top judging from the Audax frequency response.
L-Pad (Driver Attenuation Circuit) Designer / Calculator
I don't know why you are thinking you need six sets for tweeters. You have only changed two. The Zobel has to be calculated for each tweeter. I would recommend bog standard 50V NP electrolytics here. You NEED the resistance or you will get some bass peakiness.
actually ive changed the tweeter in all 6 speakers top the audax, some years ago.
I did a test on the mid by bridging the cap and it came to life. so looks like a dried out cap.
yes they do sound bright. was the 3db a calculated reduction to bring it inline with the volume from the other drivers? or am I going to have to try different values until I get the right level.
would the zobel be a better solution than the straight resistor route then?
I did a test on the mid by bridging the cap and it came to life. so looks like a dried out cap.
yes they do sound bright. was the 3db a calculated reduction to bring it inline with the volume from the other drivers? or am I going to have to try different values until I get the right level.
would the zobel be a better solution than the straight resistor route then?
tried today with the mid and bass recapped, waiting for the 3.9uf. sounded good so tried the 2.2 and 15 and the difference is quite subtle, definitely more balanced though. before the tweeter was a bit over powering. ill see what its like with the new cap in when I get it.
tried one just recapped, Christ felt like having my ears syringed. Im guessing some of the top end was being attenuated by the 4uf cap that had started to go.
will defo need those resistors in there. even with them it still seems a little bright. though they will be spending there days running off Yamaha amps, so as these are warm it might sound ok. at the moment im testing them on an old Denon PMA-100M.
will defo need those resistors in there. even with them it still seems a little bright. though they will be spending there days running off Yamaha amps, so as these are warm it might sound ok. at the moment im testing them on an old Denon PMA-100M.
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3.3R and 10R, I'd reckon. But you should have listened to me and done the Zobel thing. It's easier really. 😀
so with the zobel thingy would I need just some cheap poly's or eletro's for the 0.68uf? could I then use a variable resistor to find the right value for the resistor that goes in front of the filter. would the zobel circuit still use the 7.5ohm suggested?
ok tried them on the Yamaha and they sound totally different.
ive got one with the 2.2 in series and the 15 in parallel which sounds quite tame on high notes, and the other just has the 15 ohm in parallel (Maplin didn't have another 2.2, god sake). the one with the 15 ohm in parallel I think sounds brighter and better on this amp.
do I need to change the 15 ohm to balance it better, or can I leave them just with the 15 ohm and remove the 2.2?
ive got one with the 2.2 in series and the 15 in parallel which sounds quite tame on high notes, and the other just has the 15 ohm in parallel (Maplin didn't have another 2.2, god sake). the one with the 15 ohm in parallel I think sounds brighter and better on this amp.
do I need to change the 15 ohm to balance it better, or can I leave them just with the 15 ohm and remove the 2.2?
No, nothing will break. Let's see, 15 ohms in parallel with 6 ohms tweeter is about 5 ohms. Just a bit of impedance flattening. Won't affect level much except at the bottom end around the Fs resonance, which will be slightly tamed.
ok this is weird opened the one that sounds a bit brighter and its got the 2.2 in it, as I couldn't remember which one id done by the time id got them home.
this don't make sense. ill try some tones (as I was using music, so might be difficult to tell) tonight and use my sons ipad to measure the output. maybe the mid is in better shape in one than the other. but this is a total reversal of what they did at work.
thanks for the continuing support system7.
this don't make sense. ill try some tones (as I was using music, so might be difficult to tell) tonight and use my sons ipad to measure the output. maybe the mid is in better shape in one than the other. but this is a total reversal of what they did at work.
thanks for the continuing support system7.
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