Hey everyone,

I am an undergrad in ECE and I am working on building the box for a
double vented 500W subwoofer. I want to light up the inside with some
kind of blue light so that it shines out the side (thick clear
material) and through the two vents. I also want to put orange LEDs
around the outside of the speaker (I go to the university of illinois,
school colors). I want the lights to pulse with the bass of the
subwoofer though. I haven't taken enough courses to design my own
circuits yet, so I have been googling for hours looking for circuits
that involve a mic and a low-pass frequency filter. I have a few
questions that I am hoping someone can give me insight on:

1) Will there be a problem with using a microphone inside the box? I
am wondering if the lights will come on out of phase with the beat and
whether or not it will just always be on because its inside the box.

2) Would it be smarter to tap into the two wires going into the woofer
instead of using a mic? And if so, will the high current be a problem
for such a simple circuit? Would it be more effective to put it in
series or parallel with the woofer? Are there overload concerns with
hooking it up to a 500w amp?

3) Am I going about this all wrong? I am open to advice and to
alternative to what my current thoughts are. I am also unsure of how
to power the circuit if its a seperate one with a mic. I don't know if
tapping off the transformer is such a good idea, seeing as its a 250$
amp.

I appreciate any feedback. Thanks for your time.

Hey everyone,

I am an undergrad in ECE and I am working on building the box for a
double vented 500W subwoofer. I want to light up the inside with some
kind of blue light so that it shines out the side (thick clear
material) and through the two vents. I also want to put orange LEDs
around the outside of the speaker (I go to the university of illinois,
school colors). I want the lights to pulse with the bass of the
subwoofer though. I haven't taken enough courses to design my own
circuits yet, so I have been googling for hours looking for circuits
that involve a mic and a low-pass frequency filter. I have a few
questions that I am hoping someone can give me insight on:

1) Will there be a problem with using a microphone inside the box?

am wondering if the lights will come on out of phase with the beat and
whether or not it will just always be on because its inside the box.

2) Would it be smarter to tap into the two wires going into the woofer
instead of using a mic? And if so, will the high current be a problem
for such a simple circuit?
Would it be more effective to put it in
series or parallel with the woofer? Are there overload concerns with
hooking it up to a 500w amp?

3) Am I going about this all wrong? I am open to advice and to
alternative to what my current thoughts are. I am also unsure of how
to power the circuit if its a seperate one with a mic. I don't know if
tapping off the transformer is such a good idea, seeing as its a 250$
amp.

Hey everyone,

I am an undergrad in ECE and I am working on building the box for a
double vented 500W subwoofer. I want to light up the inside with some
kind of blue light so that it shines out the side (thick clear
material) and through the two vents. I also want to put orange LEDs
around the outside of the speaker (I go to the university of illinois,
school colors). I want the lights to pulse with the bass of the
subwoofer though. I haven't taken enough courses to design my own
circuits yet, so I have been googling for hours looking for circuits
that involve a mic and a low-pass frequency filter. I have a few
questions that I am hoping someone can give me insight on:

1) Will there be a problem with using a microphone inside the box? I
am wondering if the lights will come on out of phase with the beat and
whether or not it will just always be on because its inside the box.

2) Would it be smarter to tap into the two wires going into the woofer
instead of using a mic? And if so, will the high current be a problem
for such a simple circuit? Would it be more effective to put it in
series or parallel with the woofer? Are there overload concerns with
hooking it up to a 500w amp?

3) Am I going about this all wrong? I am open to advice and to
alternative to what my current thoughts are. I am also unsure of how
to power the circuit if its a seperate one with a mic. I don't know if
tapping off the transformer is such a good idea, seeing as its a 250$
amp.

I appreciate any feedback. Thanks for your time.

Hey everyone,

I am an undergrad in ECE and I am working on building the box for a
double vented 500W subwoofer. I want to light up the inside with some
kind of blue light so that it shines out the side (thick clear
material) and through the two vents. I also want to put orange LEDs
around the outside of the speaker (I go to the university of illinois,
school colors). I want the lights to pulse with the bass of the
subwoofer though. I haven't taken enough courses to design my own
circuits yet, so I have been googling for hours looking for circuits
that involve a mic and a low-pass frequency filter. I have a few
questions that I am hoping someone can give me insight on:

1) Will there be a problem with using a microphone inside the box? I
am wondering if the lights will come on out of phase with the beat and
whether or not it will just always be on because its inside the box.

2) Would it be smarter to tap into the two wires going into the woofer
instead of using a mic? And if so, will the high current be a problem
for such a simple circuit? Would it be more effective to put it in
series or parallel with the woofer? Are there overload concerns with
hooking it up to a 500w amp?

3) Am I going about this all wrong? I am open to advice and to
alternative to what my current thoughts are. I am also unsure of how
to power the circuit if its a seperate one with a mic. I don't know if
tapping off the transformer is such a good idea, seeing as its a 250$
amp.

I appreciate any feedback. Thanks for your time.

Jacob.Block@gmail.com wrote:
Hey everyone,

I am an undergrad in ECE and I am working on building the box for a
double vented 500W subwoofer. I want to light up the inside with some
kind of blue light so that it shines out the side (thick clear
material) and through the two vents. I also want to put orange LEDs
around the outside of the speaker (I go to the university of illinois,
school colors). I want the lights to pulse with the bass of the
subwoofer though. I haven't taken enough courses to design my own
circuits yet, so I have been googling for hours looking for circuits
that involve a mic and a low-pass frequency filter. I have a few
questions that I am hoping someone can give me insight on:

1) Will there be a problem with using a microphone inside the box? I
am wondering if the lights will come on out of phase with the beat and
whether or not it will just always be on because its inside the box.

2) Would it be smarter to tap into the two wires going into the woofer
instead of using a mic? And if so, will the high current be a problem
for such a simple circuit? Would it be more effective to put it in
series or parallel with the woofer? Are there overload concerns with
hooking it up to a 500w amp?

3) Am I going about this all wrong? I am open to advice and to
alternative to what my current thoughts are. I am also unsure of how
to power the circuit if its a seperate one with a mic. I don't know if
tapping off the transformer is such a good idea, seeing as its a 250$
amp.

I appreciate any feedback. Thanks for your time.



Here's an interesting experiment you can try
that may give you what you want with a bjt.

Wind some (10 ?) turns of hookup wire around one
of the wires that connects the subwoofer speaker
to the circutry that drives it to make a pickup
coil. Then do this:

PNP
+ 12 --------------------- ---+
e\ /c |
- |
------ ----- | [1K]
|Pickup|--|~ +|---[1K]---+ |
| | | BR | a| [LED]
| Coil |--|~ -|---+ [D1] |
------ ----- | | |
| [D2] |
| | |
Gnd ----------------+------+----+

On Sat, 27 Jan 2007 18:38:48 GMT, ehsjr <ehsjr@bellatlantic.net
wrote:


Jacob.Block@gmail.com wrote:

Hey everyone,

I am an undergrad in ECE and I am working on building the box for a
double vented 500W subwoofer. I want to light up the inside with some
kind of blue light so that it shines out the side (thick clear
material) and through the two vents. I also want to put orange LEDs
around the outside of the speaker (I go to the university of illinois,
school colors). I want the lights to pulse with the bass of the
subwoofer though. I haven't taken enough courses to design my own
circuits yet, so I have been googling for hours looking for circuits
that involve a mic and a low-pass frequency filter. I have a few
questions that I am hoping someone can give me insight on:

1) Will there be a problem with using a microphone inside the box? I
am wondering if the lights will come on out of phase with the beat and
whether or not it will just always be on because its inside the box.

2) Would it be smarter to tap into the two wires going into the woofer
instead of using a mic? And if so, will the high current be a problem
for such a simple circuit? Would it be more effective to put it in
series or parallel with the woofer? Are there overload concerns with
hooking it up to a 500w amp?

3) Am I going about this all wrong? I am open to advice and to
alternative to what my current thoughts are. I am also unsure of how
to power the circuit if its a seperate one with a mic. I don't know if
tapping off the transformer is such a good idea, seeing as its a 250$
amp.

I appreciate any feedback. Thanks for your time.



Here's an interesting experiment you can try
that may give you what you want with a bjt.

Wind some (10 ?) turns of hookup wire around one
of the wires that connects the subwoofer speaker
to the circutry that drives it to make a pickup
coil. Then do this:



If you wind turns around another wire, the coupling is zero.

PNP
+ 12 --------------------- ---+
e\ /c |
- |
------ ----- | [1K]
|Pickup|--|~ +|---[1K]---+ |
| | | BR | a| [LED]
| Coil |--|~ -|---+ [D1] |
------ ----- | | |
| [D2] |
| | |
Gnd ----------------+------+----+



This circuit blows out the PNP as soon as you turn on the +12.

John

John Larkin wrote:
On Sat, 27 Jan 2007 18:38:48 GMT, ehsjr <ehsjr@bellatlantic.net
wrote:


Jacob.Block@gmail.com wrote:

Hey everyone,

I am an undergrad in ECE and I am working on building the box for a
double vented 500W subwoofer. I want to light up the inside with some
kind of blue light so that it shines out the side (thick clear
material) and through the two vents. I also want to put orange LEDs
around the outside of the speaker (I go to the university of illinois,
school colors). I want the lights to pulse with the bass of the
subwoofer though. I haven't taken enough courses to design my own
circuits yet, so I have been googling for hours looking for circuits
that involve a mic and a low-pass frequency filter. I have a few
questions that I am hoping someone can give me insight on:

1) Will there be a problem with using a microphone inside the box? I
am wondering if the lights will come on out of phase with the beat and
whether or not it will just always be on because its inside the box.

2) Would it be smarter to tap into the two wires going into the woofer
instead of using a mic? And if so, will the high current be a problem
for such a simple circuit? Would it be more effective to put it in
series or parallel with the woofer? Are there overload concerns with
hooking it up to a 500w amp?

3) Am I going about this all wrong? I am open to advice and to
alternative to what my current thoughts are. I am also unsure of how
to power the circuit if its a seperate one with a mic. I don't know if
tapping off the transformer is such a good idea, seeing as its a 250$
amp.

I appreciate any feedback. Thanks for your time.



Here's an interesting experiment you can try
that may give you what you want with a bjt.

Wind some (10 ?) turns of hookup wire around one
of the wires that connects the subwoofer speaker
to the circutry that drives it to make a pickup
coil. Then do this:



If you wind turns around another wire, the coupling is zero.

Right. It is wound around one wire.

John Larkin wrote:
On Sat, 27 Jan 2007 18:38:48 GMT, ehsjr <ehsjr@bellatlantic.net
wrote:

Here's an interesting experiment you can try
that may give you what you want with a bjt.

Wind some (10 ?) turns of hookup wire around one
of the wires that connects the subwoofer speaker
to the circutry that drives it to make a pickup
coil. Then do this:



If you wind turns around another wire, the coupling is zero.

Right. It is wound around one wire.

On Sun, 28 Jan 2007 04:33:43 GMT, ehsjr <ehsjr@bellatlantic.net
wrote:


John Larkin wrote:

On Sat, 27 Jan 2007 18:38:48 GMT, ehsjr <ehsjr@bellatlantic.net
wrote:


Here's an interesting experiment you can try
that may give you what you want with a bjt.

Wind some (10 ?) turns of hookup wire around one
of the wires that connects the subwoofer speaker
to the circutry that drives it to make a pickup
coil. Then do this:



If you wind turns around another wire, the coupling is zero.

Right. It is wound around one wire.


---
Winding it around the single wire, using the wire as the core won't
work either.

The sensing coil needs to be wound like a solenoid and then wrapped,
like a toroid, around one of the wires feeding the subwoofer. It
then becomes the secondary of a current transformer, the primary
being the wire feeding the subwoofer.

John Fields wrote:
On Sun, 28 Jan 2007 04:33:43 GMT, ehsjr <ehsjr@bellatlantic.net
wrote:


John Larkin wrote:

On Sat, 27 Jan 2007 18:38:48 GMT, ehsjr <ehsjr@bellatlantic.net
wrote:


Here's an interesting experiment you can try
that may give you what you want with a bjt.

Wind some (10 ?) turns of hookup wire around one
of the wires that connects the subwoofer speaker
to the circutry that drives it to make a pickup
coil. Then do this:



If you wind turns around another wire, the coupling is zero.

Right. It is wound around one wire.


---
Winding it around the single wire, using the wire as the core won't
work either.

The sensing coil needs to be wound like a solenoid and then wrapped,
like a toroid, around one of the wires feeding the subwoofer. It
then becomes the secondary of a current transformer, the primary
being the wire feeding the subwoofer.



Thanks to both you and JL. So the experiment
would fail, unless he did it like that.

Now the question is why is there 0 coupling?
What do I need to read/study to gain the
understanding you & JL have on this? I've got
an incorrect idea(s), or a missing concept(s)
somewhere.

Ed

If you wind turns around another wire, the coupling is zero.

Right. It is wound around one wire.

Thanks to both you and JL. So the experiment
would fail, unless he did it like that.

Now the question is why is there 0 coupling?