Speaker Camp - July 2023 - Pass SLOB - Northern California

Speaker Camp 2023
With Optional Amp Camp Amp Build
Saturday, July 8, 2023
Sebastopol, California

About 1 1⁄2 hours north of San Francisco, site of the 2008 and 2022 Speaker Camps and the 2012 Amp Camp

The build: Pass Slot Loaded Open Baffle (SLOB) with Moth full range and Eminence 15” bass as featured in the Pass Lounge at Burning Amp Festival.
Two-way active design requires 4 channels of amplification. Analog active crossover is included in the kit!

The "cabinets" are pre-finished cherry wood with black base, photos from last year's camp are attached at the bottom of this post!

This is an easy build that can be done by a beginner. Approximately flatpack furniture level of difficulty. We encourage campers to bring novice family members and friends to participate/observe in the process. Previous Camps had several attendees that were in elementary, middle and high school and everyone benefited from their participation. Check out this video from last year to see the build complexity and vibe of the event.

Price is $750 for the Speaker Build
This is at or below cost of materials, resulting from a great deal of support
from Nelson Pass, who is planning to be in attendance at the camp.

21 spots available

We also have Amp Camp Amp Redux (ACA) Kits (thread here) that are perfect for powering the full range drivers.
Price is $220 per two channel ACA Redux Kit

Tools and supplies needed to build the SLOBs and ACAs will be provided.​

Details (please read!):
Please indicate your interest by filling out this google form
Say hey in the thread to let others know you'll be there or if you have any questions.
If we get more signups than spots there will be a lottery to choose participants.
If chosen, you will need to pay $750 by June 15, 2023 to keep your spot.
Spots that open after June 15 will be filled with other lottery participants, moving down the list.
If you don’t initially get a spot, there is still hope (see above).
If you can’t make it to the camp for whatever reason, you will still be able to come collect the entire kit and take it home to build.
Sorry, no refunds.
Sorry, no shipping of speaker kits. They must be taken away from the camp site after the build or picked up if for some reason you miss the build.
Car and tent camping at the site is fine the night before and the night following the camp. There is one bathroom out in the barn available for freshening up, otherwise try to be as boondocking-capable as you can.
Bring family and friends to observe or participate as appropriate. Any children in attendance will need supervision while away from the build area.
For best listening the speakers should be placed so the baffle is three feet or more away from the wall (so 1 1⁄2’ from the rear of the bass driver to the wall).


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Sign ups are still open and it looks like we won't need to run a lottery. The initial post said pay by June 15, now we'll just say pay upon signup.

We could use some help getting the word out about this event, so tell your friends and message folks who you think could be interested!
Are there still slots available for the speaker build? I would like to attend but not 100% sure I can make it on the 8th. I’ll be in Sebastopol this weekend (celebrating the 4th with family) so I know the area well. I’ve already built a pair of ACA redux amps, so it would be great to have the SLOBs to pair with them.
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I just signed up! Waiting to see if there's still an opening. Will be coming down from Seattle if there is room. I didn't see the instructions for payment so I'm assuming I'll get that in an email if I made the cut. -Dan
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Yes! It was a wonderful day at the beautiful Brock home and gardens. Thank you to Liz, Dana and Nelson Brock for hosting us all (lots of effort to do so), and feeding us a delicious, healthy lunch. Thank you Nelson Pass for making this project possible, and making all of the crossovers!

The speaker baffles, boxes and Moth driver are an even more attractive package in person!


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The one and only
Joined 2001
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Yes, it was great being at the Brock's and hanging out with DIYers, not to mention the
great outdoor weather and excellent lunch.

This will be the last iteration of this particular design, as we have used up the Moths and
the OB enclosures that I had made for them many years ago. Next time we will have to
do something different.

Talking to one participant at the end I discovered that he did not know that best operation
with this system is running with the phase reversed between the woofer and full range by
switch the +/- wiring between the amp and drivers. This can be done on either, but
fulfills the Linkwitz requirement for the crossover.

Oddly, the system measures relatively flat either way, but is a bit flatter and has better
phase response this way.