Dayton Audio Box Build

[ciaonzo 5,000+ posts]

Yep, sounds right.

You might try and set output at Fb (tuning frequency) because it's usually the lowest impedance the amplifier will see, since 50Hz will be in the area where the impedance peaks are higher on either side of Fb. I'm sure that the actual impedance at Fb will also be higher than 1 ohm so you will need to factor that in when you work the formula. Does PK have the impedance plot for that enclosure workup? Maybe he can quote the actual impedance at Fb for you.

 

[ciaonzo 5,000+ posts]

I still don't like that driver for a ported enclosure that you intend to throw power at, BL is too low at about 9.3

 

[Wiz Khalifla_85]

 

[ciaonzo 5,000+ posts]

That looks really good, probably as ideal as it gets for a nice resistive load for the amplifier to "see" and the peaks are pretty benign. That means the amplifier is able to deliver gobs of current with ease over a wide range, all while cone motion is controlled. I suspect there is some decent excursion in the mid to upper 30's but the rest is pretty well damped. The enclosure is really productive (efficient) but the driver is a low BL design so it can only harness so much thermal energy before thermal compression sets in. I think that is the conundrum that you are experiencing. 

28-29Hz (Fb) is where I would set output voltage. 50Hz is not in the .8 to 1 ohm region like 28-29Hz is. 

The other thing I would do is lower your LP filter in order to limit the power the driver will receive in the upper frequencies. I like the balance that a 50Hz low pass has to offer. Is your front stage pretty decent?

 

[ciaonzo 5,000+ posts]

can only harness so much thermal energy before thermal compression sets in.

I meant to say can only harness so much POWER before thermal compression sets in.

 

[Wiz Khalifla_85]

That looks really good, probably as ideal as it gets for a nice resistive load for the amplifier to "see" and the peaks are pretty benign. That means the amplifier is able to deliver gobs of current with ease over a wide range, all while cone motion is controlled. I suspect there is some decent excursion in the mid to upper 30's but the rest is pretty well damped. The enclosure is really productive (efficient) but the driver is a low BL design so it can only harness so much thermal energy before thermal compression sets in. I think that is the conundrum that you are experiencing. 

28-29Hz (Fb) is where I would set output voltage. 50Hz is not in the .8 to 1 ohm region like 28-29Hz is. 

The other thing I would do is lower your LP filter in order to limit the power the driver will receive in the upper frequencies. I like the balance that a 50Hz low pass has to offer. Is your front stage pretty decent?

 I have a total of 4 6.5s. Two in the front and two in the rear.. All powered off the Kenwood KDC-X497

[SIZE=12pt]https://www.crutchfield.com/S-Ug4dhKnVysi/p_158GS1720/Sony-XS-GS1720.html[/SIZE]