Open Baffle High Efficiency speakers, setup for reference

[RShark]

Been hijacking this topic and this might be a little to the side of diy but use this setup as a reference once in a while to remember the past.
Open Baffle has been on my mind for a while and next project will likely be something in that area. Been researching how musical equipment manufacturers plan the openings in the back of guitar and bass cabinets.

1970 Newcomb RT-1260v with dual 10" speakers and new diamond stylus

 

[Todd Anderson]

Is that your gear?

 

[RShark]

Is that your gear?

Yes

 

[Tim Hector]

I can certainly add some advice if you have specific questions. Getting decent bass is the real trick. If you are going to be successful. You will need to look for higher qts woofers. You'll need to be able to measure the response curves or choose and purchase known products that we can accurately predict without the need of measurements.

 

[RShark]

Have a DATS V3 and UMM-6 & IMM-6
(Get most use of the DATS V3 for crossover building)

 

[Tim Hector]

Since you have a dat.... woofers that have a qts of .6 to .8 with medium to high vas will work reasonably well in an open baffle. You will see several designs that add a second woofer and cross it low to reinforce low frequency. This can make a noticeable difference. I hope this helps in some way.

 

[RShark]

I can certainly add some advice if you have specific questions. Getting decent bass is the real trick. If you are going to be successful. You will need to look for higher qts woofers. You'll need to be able to measure the response curves or choose and purchase known products that we can accurately predict without the need of measurements.

When Peavey, Fender or others built guitar/bass cabinets (usually older versions) there would be a 'slot' opening on the back (on combo cabinets you would store the power cable there). That slot was usually full width side to side but only the center 'approximately a third' was open vertically (sometimes it was on top behind the amp on combo's). Am looking for any research/rules/reqs they had for those in the day. "If not learning from history what mistakes are we recreating??"

Anyway that is the direction of the quest so far and there are plenty of drivers now days to choose from and will always try to use Madisound first as they have always been great to work with (they use to sell/rebuild DynAudio drivers is how found them).

 

[RShark]

Since you have a dat.... woofers that have a qts of .6 to .8 with medium to high vas will work reasonably well in an open baffle. You will see several designs that add a second woofer and cross it low to reinforce low frequency. This can make a noticeable difference. I hope this helps in some way.

Also want to understand H chambers more as in someways they are a ~quasi open baffle. Have done lots of ..wierd chambers over the years and wonder how much 'tuning' of an H-box (if thought of in a 6th order bandpass way) could be gotten away with.

And Thanks for your info too...

 

[Tim Hector]

A slot is very different than open baffle. Slot loaded woofers are essentially ported. They like low to medium qts. In the .33 to .4 range. Open baffle have nothing behind them to support back pressure that help so much in producing bass. Slots themselves produce bass reinforcing the woofer.