Video

I agree no enclosure is not viable for nearly all subs except for a few and those sound like crap too. An enclosure is necessary to limit power waste and give the bass some structure. This is nothing I would even consider attempting. Sealed or ported that's it

@@adsph fun stuff. 👌😊

@@abxaudiophiles always get that impression from you.

@@54tristin It’s covered in the video. 👌👌

@@DaleCrommie will do!! 👌👌

@@abxaudiophilesThank you.🔥👍

@@werefed8613 Still use it to this day! Love it. 😍

@@jonhoskins3795 Will do!! 👌👌

@@humanitech We do that too. Running the new 2502 currently. Put the plate amps are simple, full range crossover and variable phase. I like the versatility of the plate amps. Both great options tho.

@@JensenTech - Sure. There’s a lot on our website and links to where we get our drivers. It basically just the lower section of our DIY baffles. Think of our big baffle and just cut the speaker in half. Same slot loading etc… Then we just screwed a plate amp to the side and rocked out. 👌👌 But yea. Check the ABX Website as well as La Dolce Audio. Lots of shared stuff there. Our Discord houses it all as well. Cheers. 🍻

I think Terry measured 27db at -3

@@rnulfaasum2739 What exactly is “slot loading” then?

Some baffles are better than others for sure, as is any speaker really. Maybe you just didn’t hear the right set. 😊😊👌

Always fun to experiment. 👌👌

Yea the Forte II are really only effective down to about 45-50hz, shut the sub down and the room thins out immensely. I’ll do a comparison video soon. Good call.

Open baffle implies the front and rear of the driver is open and allow propagation of the sound waves. Slot loading the front of the baffle is essentially a mechanical inductor that adjusts the QTs, sensitivity, and bass response slightly. Think of it as more of a mechanical crossover vs a bunch of capacitors and resistors. It’s 100% an open baffle.

​@@abxaudiophileswhat you mention here is a big point of interest for me! I'll be really grateful if you'd share some experience. The slot definitely affects speaker parameters but how? I assume it slightly lowers the fs, rises qts, lowers sensitivity a bit (thats a question since we deal with front-back cancellation). Also I think it alters directivity pattern making it somewhat cardioidish. Am I right?

I’m not being critical, just curious and interested in this design.

All good. I’ve ran REW sweeps on the Forte II. Effective bass down to 50hz really and at 45hz it’s dropping off way fast. The sub woofer is pretty flat down to 30hz and about -3db at 27hz. If you were in room with me and we shut the sub off, you would say WTH… 😆😆👌👌

@@abxaudiophiles That’s great!

Well played sir.

Oh no… 97db sensitive. 20 watts rocks the house. 27hz and BOOM!!!! 💥

Great idea

The drivers are crossed over at 50hz. I run through it all in the video.. Gotta watch the video.. HA

No mention of crossovers or high pass filters in this video…

@@mikerick6955 - Literally covered what they were crossed over at, and It is a damn plate amp with variable crossover and phase.. Make it what ya want.. Not sure what else to say

@@abxaudiophiles I’m sorry but you didn’t. Maybe it got edited out or something but I’ve watched the video three times and there’s no mention of crossover level or high passing the Fortes. Don’t get me wrong, I’m intrigued by OB mains and subs, just curious same as @jungtarcph

@@mikerick6955 subs crossed over at 50 hz. 👌

I love options. 👌👌👌

Oh, guess we need to have a listening session ASAP .... HA

I assume you mean Quad electrostatics, the only way you will get cone movement quicker is buy using multiple high efficiency so pro drivers for the low end bass and using DSP. but I don't think you have this correct, the lower frequencies don't need to have "quick" drivers as you say. The most important factor for bass is the volume of air moved and the motor BL. So air volume to BL ratio. Bassically (excuse the pun) you want to move vast amounts of air the lower the frequency, but you need motor strength to do it. Your electrostatics will increase in efficiency as the frequency goes up, because you will be moving less air, hence why you don't turn them up, but if you cross to a sub you will find the volume knob being able to go higher with you electrostatics.

@@shanerorko8076 Have you heard of the moving magnet subs used in pro gear? Produce 5 to 30 Hz and can handle lots of power since the coils are mounted on the speaker frame which act as heat sinks. No flex wires to fail as well. Not very efficient, but would do great for pro sound stuff. I think what people perceive as quick bass is the attack and decay. Especially the attack, the first pressure wave of air that hits you.

@@zulumax1 I have seen those subs, they are for very big areas. for a smaller room, eight six inch speakers or twelve six inch speakers could pressurize the room sufficiently. But low frequency requires slow coupling to the air as the air can't couple any faster at the low frequencies. So as long as you have enough cone area, you then require cone speed which, increases in the total BL will help.

As soon as I get my stuff back from Kelly.... ;)

Now that is some nice bass

This is some smooth, fast, defined bass, I would have liked something with sustained low bass or organ to see if there was any cone flap or even Tracey Chapman Crossroads, there are several tracks on this that will test a subwoofer

@@staceymangham Agreed. 👍🏼

@@staceymangham Due to the sensitivity and size of the driver there is very little movement of the driver for the bass created. I’d say at listening levels with bass pumping the drive is moving 1/8” or less. Maybe getting close to 1/4”…. No baffle slap to be found.

@@welderfixer LETS GO!!! 👌👌😍😍

@@abxaudiophiles I may be wacked, but I kinda like slightly hollow and tame sounding speakers/systems. O-B speakers just might give that old fashion sound I've been looking for. I wish I had the funds to come out and listen to the system you and your friends have built. Sux to be bankrupt!

@@mcjonner true stereo subs are so good. 👌👌👌👌

@@mcjonner There’s always next time!! PS, these bass drivers are 97db sensitive you’ll get all that bass off a little 50 watt amp. 500 would instantly destroy the drivers if turned up. 😂😂😂👌

​@@abxaudiophiles Oh wow lol nice

@@mcjonner Yes sir !! This is great cus we can find a nice lower watt, higher quality plate amp to really make these ladies shine. 👌👌

@@middleearthltd I have yet to run sweeps, but will soon, I’m sensing about 25-30hz effective, maybe lower.

@@abxaudiophiles Excellent 🙏

I get that alot.. ;) Thank you for watching

They are pretty budget-friendly, but not bad at all, really. Kinda loving the plate amp right now.. HA

Me too.. .HA Thank you

Let's go!! Enjoy my friend.

Thank you.. ;) I was actually speaking with Dynaudio last week.. Fingers crossed. :)

@@wrongIQ Not a fan of DSD, so no, and yea, more hard work in driver and baffle design on Terrys part vs a miracle, but yea, I get it. 😂😆😆

@@abxaudiophiles I'm seriously on my way to try this or similar design (12" speakers ordered and being delivered). Is there any secret? Ok I got the idea of the hole smaller than Sd. But I still don't get what else do you do to have THIS level of lower frequency sound waves

@@wrongIQ No secrets. Build the design we’ve worked on for almost two years and get the results. 👌👌

@@abxaudiophiles all right! I'll post reports of my progress into discord

@@BrianHall-Oklahoma - Yea A6 and Wiim streamer sections are LIGHT YEARS behind the Lumin. Don’t take my review the wrong way. 😂👌

Any time!

Preferences are real. 😉😊👍