[[email protected]]

Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Thanks.

[Laurence Payne]

On 16 Oct 2006 08:02:37 -0700, wrote:

Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Thanks.

[Laurence Payne]

On 16 Oct 2006 08:02:37 -0700, wrote:

Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Tape a Kleenex over it?

[Serge Auckland]

Laurence Payne wrote:
On 16 Oct 2006 08:02:37 -0700, wrote:

Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Tape a Kleenex over it?

That would be the special 3dB Kleenex. Standard Kleenex is 2.2dB. You
could use two thicknesses of Andrex, but that would be 3.5dB


A more reliable way is to use a single resistor in series with the
tweeter. If you know the tweeter is 8ohms, an 8 ohm resistor will give
you a 3dB drop. However, without knowing full details of the crossover,
the standard impedance of the tweeter could have been taken into account
in designing the crossover slope and frequency, any impedance matching
network, or notch filter.


S.

[GregS]

In article , Laurence Payne lpayne1NOSPAM@dslDOTpipexDOTcom wrote:
On 16 Oct 2006 08:02:37 -0700, wrote:

Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Tape a Kleenex over it?

I have done something like that, and so has others.

For a quick fix, put a 4ohm series resistor going to
the tweeter, and it must be at least 5 watts, but may fry if
signal get up there. This changes more than levels,
but its simple.

If it would not need to be measured or adjusted, then how did you come up with
this 3 dB thing? I would never change something without carefull listening tests.
3 dB is kind of coarse as far as changing levels in crossovers.

greg

[TimPerry]

wrote:
Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Thanks.

use a fixed L pad consisting of 2 resistors as opposed to the variable L pad
that i suspect that you are referring to.

[GregS]

In article , "TimPerry" wrote:
wrote:
Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Thanks.

use a fixed L pad consisting of 2 resistors as opposed to the variable L pad
that i suspect that you are referring to.

I was at first going to suggest that but getting resitor
values might be hard. Perhaps sombody can figure out the values
to use.


Adding a 4 ohm resistor in series with a 8 ohm tweeter is a 3 db drop.
Adding a 8 ohm resistor in series with a 8 ohm tweeter is a 6 dB drop.
I'm not getting into phase.

greg

[[email protected]]

GregS wrote:
In article , Laurence Payne lpayne1NOSPAM@dslDOTpipexDOTcom wrote:
On 16 Oct 2006 08:02:37 -0700, wrote:

Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Tape a Kleenex over it?

I have done something like that, and so has others.

For a quick fix, put a 4ohm series resistor going to
the tweeter, and it must be at least 5 watts, but may fry if
signal get up there. This changes more than levels,
but its simple.

If it would not need to be measured or adjusted, then how did you come up with
this 3 dB thing? I would never change something without carefull listening tests.
3 dB is kind of coarse as far as changing levels in crossovers.

greg


Thanks for all the quick replies. (except you, Kleenex guy :-P )

Based on frequency response graphs I have seen for the speakers,
reducing the tweeter by 3db would bring them more in line with my old
speakers. This also "sounds" about right.

You suggest a 4ohm resistor, but Serge suggested an 8ohm - would it be
best to measure the tweeter's resistance and add a resistor in series
that matched it?

Will doing this adversly affect the sound quality coming from the
tweeter?


..

[Serge Auckland]

wrote:
GregS wrote:
In article , Laurence Payne lpayne1NOSPAM@dslDOTpipexDOTcom wrote:
On 16 Oct 2006 08:02:37 -0700, wrote:

Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.
Tape a Kleenex over it?
I have done something like that, and so has others.

For a quick fix, put a 4ohm series resistor going to
the tweeter, and it must be at least 5 watts, but may fry if
signal get up there. This changes more than levels,
but its simple.

If it would not need to be measured or adjusted, then how did you come up with
this 3 dB thing? I would never change something without carefull listening tests.
3 dB is kind of coarse as far as changing levels in crossovers.

greg


Thanks for all the quick replies. (except you, Kleenex guy :-P )

Based on frequency response graphs I have seen for the speakers,
reducing the tweeter by 3db would bring them more in line with my old
speakers. This also "sounds" about right.

You suggest a 4ohm resistor, but Serge suggested an 8ohm - would it be
best to measure the tweeter's resistance and add a resistor in series
that matched it?

I suggested 8 ohms incorrectly, too quick on the keyboard by half! Greg
is substantially right with his figures - 4 ohms for 3dB (near enough) 8
ohms for 6 dB.


Will doing this adversly affect the sound quality coming from the
tweeter?


It may well do, it depends on the crossover design.

S.
.

[Laurence Payne]

On Mon, 16 Oct 2006 16:22:07 +0100, Serge Auckland
wrote:

Tape a Kleenex over it?

That would be the special 3dB Kleenex. Standard Kleenex is 2.2dB. You
could use two thicknesses of Andrex, but that would be 3.5dB


A more reliable way is to use a single resistor in series with the
tweeter. If you know the tweeter is 8ohms, an 8 ohm resistor will give
you a 3dB drop. However, without knowing full details of the crossover,
the standard impedance of the tweeter could have been taken into account
in designing the crossover slope and frequency, any impedance matching
network, or notch filter.

On the contrary, the Kleenex is a time-honoured technique, requires no
modification, opening up or soldering, and has the added advantage of
providing an immediate remedy in the event of an unintended snot
emergency. It is also the simple solution. Hence it wins hands down.

As you say, either way experimentation would be required.

[Laurence Payne]

On 16 Oct 2006 08:35:35 -0700, wrote:


Thanks for all the quick replies. (except you, Kleenex guy :-P )

Why do you insist on a complicated solution? We used tissue in the
NS-10 for years.

[Eeyore]

Serge Auckland wrote:

Laurence Payne wrote:
On 16 Oct 2006 08:02:37 -0700, wrote:

Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Tape a Kleenex over it?

That would be the special 3dB Kleenex. Standard Kleenex is 2.2dB. You
could use two thicknesses of Andrex, but that would be 3.5dB

A more reliable way is to use a single resistor in series with the
tweeter. If you know the tweeter is 8ohms, an 8 ohm resistor will give
you a 3dB drop.

No it won't. It would be 6dB but also it'll mess up the crossover.

Graham

[Eeyore]

GregS wrote:

In article , "TimPerry" wrote:
wrote:
Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Thanks.

use a fixed L pad consisting of 2 resistors as opposed to the variable L pad
that i suspect that you are referring to.

I was at first going to suggest that but getting resitor
values might be hard. Perhaps sombody can figure out the values
to use.

Adding a 4 ohm resistor in series with a 8 ohm tweeter is a 3 db drop.
Adding a 8 ohm resistor in series with a 8 ohm tweeter is a 6 dB drop.
I'm not getting into phase.

Keeping to standard values, use a 2.2 ohm series R and 22 ohm across the tweeter.

Graham

[Bertie the Bunyip]

Eeyore wrote in
:



Serge Auckland wrote:

Laurence Payne wrote:
On 16 Oct 2006 08:02:37 -0700, wrote:

Hi,

Is there a simple way to reduce the output level of a tweeter in
an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the
back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Tape a Kleenex over it?

That would be the special 3dB Kleenex. Standard Kleenex is 2.2dB. You
could use two thicknesses of Andrex, but that would be 3.5dB

A more reliable way is to use a single resistor in series with the
tweeter. If you know the tweeter is 8ohms, an 8 ohm resistor will
give
you a 3dB drop.

No it won't. It would be 6dB but also it'll mess up the crossover.

Graham


netttkkkkkpoping toerag


Bertie

[Bertie the Bunyip]

Eeyore wrote in
:



GregS wrote:

In article ,
"TimPerry" wrote:
wrote:
Hi,

Is there a simple way to reduce the output level of a tweeter in
an 8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work,
but I would prefer something small that could easily be wired onto
the back of the tweeter, and also something that wouldn't need to
be measured/adjusted.

Thanks.

use a fixed L pad consisting of 2 resistors as opposed to the
variable L pad that i suspect that you are referring to.

I was at first going to suggest that but getting resitor
values might be hard. Perhaps sombody can figure out the values
to use.

Adding a 4 ohm resistor in series with a 8 ohm tweeter is a 3 db
drop. Adding a 8 ohm resistor in series with a 8 ohm tweeter is a 6
dB drop. I'm not getting into phase.

Keeping to standard values, use a 2.2 ohm series R and 22 ohm across
the tweeter.

Graham


froup sniping Fjukkkwit


bertie

[Phil Allison]

wrote in message
oups.com...


** Canuck Groper Alert !


Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work,


** Don't you mean " variable L pad " ???

Pays to get your terms right.


but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.


** Then don't use a variable L pad.

Use a fixed one.

Just two power resistors.



......... Phil

[Mr.T]

"Serge Auckland" wrote in message
...
A more reliable way is to use a single resistor in series with the
tweeter. If you know the tweeter is 8ohms, an 8 ohm resistor will give
you a 3dB drop.

An 8 ohm series resistor would halve the voltage and current, and give a 6dB
drop, not 3dB. And also unfortunately only at a couple of frequencies. Since
the impedance of the tweeter is usually not flat over the frequency range,
the attenuation with a single series resistor will vary, and by more than
3dB in some cases.

However, without knowing full details of the crossover,
the standard impedance of the tweeter could have been taken into account
in designing the crossover slope and frequency, any impedance matching
network, or notch filter.

Yep, you would need to keep the impedance seen by the Xover the same.

MrT.

[GregS]

In article , "Mr.T" MrT@home wrote:

"Serge Auckland" wrote in message
...
A more reliable way is to use a single resistor in series with the
tweeter. If you know the tweeter is 8ohms, an 8 ohm resistor will give
you a 3dB drop.

An 8 ohm series resistor would halve the voltage and current, and give a 6dB
drop, not 3dB. And also unfortunately only at a couple of frequencies. Since
the impedance of the tweeter is usually not flat over the frequency range,
the attenuation with a single series resistor will vary, and by more than
3dB in some cases.

However, without knowing full details of the crossover,
the standard impedance of the tweeter could have been taken into account
in designing the crossover slope and frequency, any impedance matching
network, or notch filter.

Yep, you would need to keep the impedance seen by the Xover the same.

This is true, however there have been tons of speakers built forgetting
about that. I would say some famous brands at that.

greg

[Daddy]

wrote:
Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Thanks.

Go with Eeyore's suggestion. It'll work. 22 ohm resistor across the
tweeter, and a 2.2 ohm in series. It keeps the impedance about the same
and attenuates the power the right amount. Use resistors that are rated
(power-wise, or watts) at about 30% of what your speaker system is
seeing (amplifier output).

[Daddy]

Oh, the 22 ohm resistor only needs to handle 1/3 the power of the 2.2
ohm resistor.

[GregS]

In article om, "Daddy" wrote:
Oh, the 22 ohm resistor only needs to handle 1/3 the power of the 2.2
ohm resistor.

The actual resistor value is hard to predict. A typical HiFi
speaker tweeters rating may be 5-10% average of total speaker
power. Even less if peak power output of the amplifer is used.
Its hard to hang large resistors on the back of some tweeters.
A bead od rtv silicone will attach 10 watt resistors to the backs
of tweeter magnets. Just don't use hot melt glue, except I
sometimes I use a dab to semi attach prior to using the silicone which sets up in
longer time.

greg

[Daddy]

GregS wrote:
In article om, "Daddy" wrote:
I was being conservative.

[jakdedert]

GregS wrote:
In article , "TimPerry" wrote:
wrote:
Hi,

Is there a simple way to reduce the output level of a tweeter in an
8ohm 3-way speaker by 3db? I suspect an 'l-pad' would work, but I
would prefer something small that could easily be wired onto the back
of the tweeter, and also something that wouldn't need to be
measured/adjusted.

Thanks.
use a fixed L pad consisting of 2 resistors as opposed to the variable L pad
that i suspect that you are referring to.

I was at first going to suggest that but getting resitor
values might be hard. Perhaps sombody can figure out the values
to use.


Adding a 4 ohm resistor in series with a 8 ohm tweeter is a 3 db drop.
Adding a 8 ohm resistor in series with a 8 ohm tweeter is a 6 dB drop.
I'm not getting into phase.

greg

Adding resistance in series is going to change the x-over frequency by
changing the load impedance. You need an L-pad to keep the impedance
constant. That said, try it...you might not be able to tell the difference.

jak