Hello
I made some very simple amps, just for learning. When i used them with my speakers (tweeter and woofer) the sound is low, tweeter almost makes no sound and no vibrations, almost all from the woofer so it doesn't sound very good, voices sound deeper,unnatural.
I thought the caps died, tried changing with 4.7uF instead of 1.8uF that were in the speaker, almost no difference same sound.
Tried putting 330uF electrolytic polarized (I know I shouldn't but i didn't have non polarized) and tweeter was noticeable now, much better sound, cleaner higher notes. I know that lower frequencies are being passed through the cap, but without it it just sounds bad, isolates almost everything.
TLDR: Tweeter almost made no sound(only the woofer), replaced 1.8uF with 330uF, much better sound, don't know is the crossover bad or my amp, and could the original amp have been made specifically for the speakers so they sound good together ?
The crossover is only one 1.8uF np cap.
Thanks
I made some very simple amps, just for learning. When i used them with my speakers (tweeter and woofer) the sound is low, tweeter almost makes no sound and no vibrations, almost all from the woofer so it doesn't sound very good, voices sound deeper,unnatural.
I thought the caps died, tried changing with 4.7uF instead of 1.8uF that were in the speaker, almost no difference same sound.
Tried putting 330uF electrolytic polarized (I know I shouldn't but i didn't have non polarized) and tweeter was noticeable now, much better sound, cleaner higher notes. I know that lower frequencies are being passed through the cap, but without it it just sounds bad, isolates almost everything.
TLDR: Tweeter almost made no sound(only the woofer), replaced 1.8uF with 330uF, much better sound, don't know is the crossover bad or my amp, and could the original amp have been made specifically for the speakers so they sound good together ?
The crossover is only one 1.8uF np cap.
Thanks
What did you do to test the amps when you built them? Is their response flat..
What type of tweeter are you using and how does it measure?
What type of tweeter are you using and how does it measure?
I did a little bit of research based on your answer, sorry for not answering before I wanted to test it all out and give the results. I figured out what I need to however I won't be doing it soon so I wanted to aswer with something.
Thanks a lot for the help.
Thanks a lot for the help.
Hi! Don't give up so easily on your first post - we're glad to help if at all possible.
You say your speakers were working OK when powered from their original amplifier.
This would suggests a problem with the amplifier that you built.
To pursue this further, you would have to provide details of the speakers, the original amp and the amp that you built.
You say your speakers were working OK when powered from their original amplifier.
This would suggests a problem with the amplifier that you built.
To pursue this further, you would have to provide details of the speakers, the original amp and the amp that you built.
I wasn't planning on quitting just pausing it a bit haha.
No they sounded ok with cap change, the original amp died long ago so I don't remember how they sounded.
The speakers are cheap AIWA ones so I wasn't surprised if they weren't the best. As I did a bit of research I realised the relations of boxes,drivers ,crossovers and all that.
I was thinking about measuring output voltage of my amp for sine wave 20-20kHz for voltage drops to see if there are any, then measure the freq response separately from woofer and tweeter in the box and design the crossover with a program.
Only problem is the best microphone I have is some karaoke microphone from a friend. Could that effect the frequency response a lot considering it's an amateur build ?
Is there anything i missed ?
No they sounded ok with cap change, the original amp died long ago so I don't remember how they sounded.
The speakers are cheap AIWA ones so I wasn't surprised if they weren't the best. As I did a bit of research I realised the relations of boxes,drivers ,crossovers and all that.
I was thinking about measuring output voltage of my amp for sine wave 20-20kHz for voltage drops to see if there are any, then measure the freq response separately from woofer and tweeter in the box and design the crossover with a program.
Only problem is the best microphone I have is some karaoke microphone from a friend. Could that effect the frequency response a lot considering it's an amateur build ?
Is there anything i missed ?
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330uf is too much for a tweeter. If it isn't blown, it will blow soon. If they had originally 1.8uF I would go no higher than 3.3uF.
Measure the tweeter with a DMM. What's the resistance ?
Please answer Galu and give us more details.
Measure the tweeter with a DMM. What's the resistance ?
Please answer Galu and give us more details.
Yes, details of speakers, original amp (or midi/micro system) and new build amp. By details, I mean model numbers and also, where possible, photographs.
I seem to remember that some midi/micro systems employed dual amplification where the tweeter was driven by a separate amplifier from the mid/bass speaker. Such speakers would not be directly compatible with an ordinary amplifier. A photograph of the rear of the speaker and its connecting terminals may help eliminate this as a possibility.
Did you build a chip or discrete amp. Is this 'deeper unnatural' sound a distant, hollow kind of sound? Are the channels the same as each other? Is the gain sufficient?
Before anyone can give you a meaningful answer, we're going to need to see your amplifier schematics.
I don't remember anything of the original amp, it was probably class AB considering both npn and pnp transistors were attached to the heat sink.
Woofer is 6ohm and tweeter is 8ohm. Correct model is AIWA SX-NR40. I thought that maybe higher frequencies were amplified more than lower as to balance it out, I don't know if this is even possible or if it makes sense, there are only 2 terminals, no separate amplification.
I took the 330uF off, thanks for the warning.
The amps I built (2 class "A" and 1 AB) were just to learn how a mosfet and bipolar transistors work, however the one I am currently using is ic amp tda7297 which should tell you more about the amplification, sound is more or less the same. I am only using one speaker atm, just for testing and such.
The sound is just deeper than it should be, most of the sound is being produced by the woofer and so it just sounds deeper than it should be,music is ok but hearing voices in normal videos like on youtube just sounds bad, there is a bit of that zzzzzz in the voices, not normal noise it just sounds like that,my sound terms are not good but I think it's just cheap bad speakers in general.
Is it possible to change the box, airflow with the ports and with a new crossover to make them a bit better or would I lose the lower notes then ?
I have accidentally overwritten the schematics of my previous amps, if it is still necessary I could remake them ?
Thanks and sorry for the late reply
Woofer is 6ohm and tweeter is 8ohm. Correct model is AIWA SX-NR40. I thought that maybe higher frequencies were amplified more than lower as to balance it out, I don't know if this is even possible or if it makes sense, there are only 2 terminals, no separate amplification.
I took the 330uF off, thanks for the warning.
The amps I built (2 class "A" and 1 AB) were just to learn how a mosfet and bipolar transistors work, however the one I am currently using is ic amp tda7297 which should tell you more about the amplification, sound is more or less the same. I am only using one speaker atm, just for testing and such.
The sound is just deeper than it should be, most of the sound is being produced by the woofer and so it just sounds deeper than it should be,music is ok but hearing voices in normal videos like on youtube just sounds bad, there is a bit of that zzzzzz in the voices, not normal noise it just sounds like that,my sound terms are not good but I think it's just cheap bad speakers in general.
Is it possible to change the box, airflow with the ports and with a new crossover to make them a bit better or would I lose the lower notes then ?
I have accidentally overwritten the schematics of my previous amps, if it is still necessary I could remake them ?
Thanks and sorry for the late reply
Best stick strictly to what you are using now. This may be several issues, maybe the amps and the speakers so it is complicated as it is.
If you are using the tweeter without the capacitor, that is worse. Use a smaller value like 10uF or less.
I'll try and borrow my friend's speakers, if they sound deep as well then it is an amp thing if not then just bad speakers I guess.
No no i put the 1.8uF back.
No no i put the 1.8uF back.
Sounds like a great idea. Do you have a multimeter so you can check your amp isn't putting out DC, so you don't damage your friends speakers?
All my amps were going through a cap.
Just checked with my friends speakers, they are ok, no deeper bass and all that.
Just checked with my friends speakers, they are ok, no deeper bass and all that.
