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In the Forum: Horn-Loaded Speakers
In the Thread: Macondo’s Midbass Project – the grown up time.

Post Subject: Relationship of rear chamber volume to FsPosted by jessie.dazzle on: 8/31/2010

First question:

With the 1.5 gallon rear chamber, the resonance is 700Hz
With the basket sealed by tape (very small rear chamber), the resonance is 49Hz

Assuming there was not a typographical error, from this we can conclude:

1) Larger rear chamber volume = Higher resonance
2) Smaller rear chamber volume = Lower resonance

???

3) With the 5 small holes punched through the tape, effectively increasing the rear chamber volume, the resonance drops to 42Hz.

Only number 3 makes sense to me.

What am I missing?

Second question:

In the image showing the taped basket, the device on the top of the stack appears to be a frequency generator. If so, can you confirm that the signal is routed through, and amplified by the table radio? This would seem logical.

The reason I ask: I have always been afraid to rout a signal from the generator into either my pre-amp or directly to my power amps. Doing so would be very convenient, but I did not want to risk damage to the equipment, as the output voltage of the generator measures significantly more than a typical source component.

Is there a safe way to rout a signal from this type of generator, directly into a pre-amp? If not, then into a power amp?

jd*

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