Any ways to find out the frequency res

[Antispammer]

hi all,

is there any way to find out the frequency response of a pair of unknown
tweeters?
like - how low it go>

the cheap way pls....i cant afford $$$$ oscilloscope or those pro meters.

[MOSFET]

Well, yes there is a way. But you will need two things; an SPL meter (they
can be had for about $30 at Radio Shack) and a test disc (or an MP3
recording)of 1/3 octave test tones. Sheffield Labs makes one in particular
that I use called "My Disc" that costs about $20.

You then play these test tones over your tweeters and record the SPL level
at each frequency (obviously, don't start at anything below about 500-1000
Hz as you could damage the tweeters). You can then plot a frequency
response curve with the numbers you get. It's a bit crude, and CERTAINLY
not the way professionals do it, but it will give you an idea of what the
usable frequency response of a set of tweeters are. Keep in mind, however,
that what this WON'T tell you is wattage capability at any given frequency.
So even though it might APPEAR that a set of tweeters can produce output at
1000 Hz, let's say, that DOES NOT mean that they SHOULD be producing that
frequency at high volumes. This is why it is always best to check with the
manufactures' specifications and what their recommended frequency range for
that particular set of tweeters are.

MOSFET

"Antispammer" > wrote in message
...
> hi all,
>
> is there any way to find out the frequency response of a pair of unknown
> tweeters?
> like - how low it go>
>
> the cheap way pls....i cant afford $$$$ oscilloscope or those pro meters.
>
>

[Antispammer]

wow....thanks mosfet.
meaning it is still dangerous if i wants to know HOW LOW it can go. anyway
thanks a lot. WIll save this for future use.

I am actually looking for a horn driver that can play 150hz onwards.
www.sammisound.com does have one that plays 150-5k. But i just couldnt find
anyone selling them online.







"MOSFET" > wrote in message
m...
> Well, yes there is a way. But you will need two things; an SPL meter
> (they
> can be had for about $30 at Radio Shack) and a test disc (or an MP3
> recording)of 1/3 octave test tones. Sheffield Labs makes one in
> particular
> that I use called "My Disc" that costs about $20.
>
> You then play these test tones over your tweeters and record the SPL level
> at each frequency (obviously, don't start at anything below about 500-1000
> Hz as you could damage the tweeters). You can then plot a frequency
> response curve with the numbers you get. It's a bit crude, and CERTAINLY
> not the way professionals do it, but it will give you an idea of what the
> usable frequency response of a set of tweeters are. Keep in mind,
> however,
> that what this WON'T tell you is wattage capability at any given
> frequency.
> So even though it might APPEAR that a set of tweeters can produce output
> at
> 1000 Hz, let's say, that DOES NOT mean that they SHOULD be producing that
> frequency at high volumes. This is why it is always best to check with
> the
> manufactures' specifications and what their recommended frequency range
> for
> that particular set of tweeters are.
>
> MOSFET
>
> "Antispammer" > wrote in message
> ...
>> hi all,
>>
>> is there any way to find out the frequency response of a pair of unknown
>> tweeters?
>> like - how low it go>
>>
>> the cheap way pls....i cant afford $$$$ oscilloscope or those pro meters.
>>
>>
>
>

[GregS]

In article >, "Antispammer" > wrote:
>wow....thanks mosfet.
>meaning it is still dangerous if i wants to know HOW LOW it can go. anyway
>thanks a lot. WIll save this for future use.
>
>I am actually looking for a horn driver that can play 150hz onwards.
>www.sammisound.com does have one that plays 150-5k. But i just couldnt find
>anyone selling them online.

There is no way in my view to use a horn that low. You basically need a mouth
with an opening much larrger than an Altec A7 has. The Altec started out about 500 or
800. Hold your hands as wide as possible. This is a minimum width, and then
you need the height. 30 Hz, you need about 16 feet. You can be inside the horns
mouth if it mates well with the interior. You can incorporate horn loading to a midrange driver.
Whats you purpose??

greg

[MOSFET]

> There is no way in my view to use a horn that low.

Remember Richard Clark's Buick? The "winningest" car in IASCA history? Now
THOSE horns probably could play down to 150Hz, they were MONSTERS (they were
so large, they were difficult to pick up)!!!!!!

To AntiSpmammer: You may want to try to track down Rickard Clark and ask for
his suggestions regarding a horn that will play that low (he practically
invented the concept of horns in the car, and is TRULY in expert in this
area). Try looking at "Autosound 2000", the company he and David Navone
started.

MOSFET