You can see in the first post here:
https://www.diyaudio.com/community/threads/cheap-and-fast-ob-literally.249984/
wow, that's a cool design. Clever way to create a subwoover with a narrow profile. I like the look of that slot versus a line of drivers and it makes a grill nor really necessary the driver cones are safely tucked away.
@nandappe Have you seen this TQWT cabinet design similar to yours for an 8" FR driver that has similar spec's to the SB20
I guess there are dozens if not hundreds of cabinet designs out there that could work.
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Scott Moose here is quite expert maybe can have wood flatpack too if I remember well
ah, nice! thanks for that. I like this a lot - the simplicity of that OB in the video with the down firing SLOB bass driver that also serves as a good foundation for securing, weighing down the vertical baffle and serving as "feet" keeping it from falling over. And it minimizes the size visually versus if the bass driver was forward facing on a much bigger baffle.
really nice active discrete jfet XO by Nelson for OB....
https://diyaudiostore.com/collections/analog-crossover-network/products/diy-biamp-6-24-crossover
https://diyaudiostore.com/collections/analog-crossover-network/products/diy-biamp-6-24-crossover
Could someone please explain to me what's the deal with the smaller cone inside the large cone? Unless it's a coaxial driver (dual voice coils and dual separate cones), I don't understand the point of sticking a smaller cone onto the big cone. How is it supposed to do anything useful? And if it really does, why isn't it used on more midrange and midbass drivers?
yeah well, using that Lowther driver you will need a lot of EQ.
This OB design begs to have Lii Audio drivers that are specifically designed for OB use and are high sensitivity drivers.
I'd bet this SB 20FRPC30-8 8" and SB 15OB350-8 15" drivers would also sound better than the drivers they used.
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is mechanic tweeter ,high is made on the center the bicone do the work .....you need a smaller driver to avoid the whizzer
If you were looking at an OB using the SB20 and the Bianco 15, what kind of baffle and x-over would you guess is decent? I’m considering my first experiment with OB and this seems like a very reasonably priced setup.
The whizzer is a smaller and lighter cone (moving mass) and does not have any surround/suspension so it can move much faster, essentially closer to what the voice coil is producing and so has higher output at the high frequencies whereas the bigger, heavier cone can't move fast enough to product those high frequencies at higher/audible loudness levels. Basically, the speaker cone has as much or more influence on the sound as the voice coil to which it is attached.
If you have a big room something like the big but simple baffle shown in this video using the more expensive Lii Audio Fast-8 (or F-8) and F-15 drivers.
If your room is smaller I'd try just using the SB20 in the smaller Betsy Baffle also shown in that video - and then add a fast subwoofer to augment the bass.
Or you can build a simple rectangular baffle of similar size to the Betsy and keep it on the floor angled up same as the Betsy.
If you don't like the SB20 in whichever baffle you could try with the higher priced Lii Fast-8.
My guess is the SLOB baffle design discussed above will probably have better performance than those simpler designs in the video, but with more work to build.
Keep in mind the Lii drivers were specifically designed for use in OB's. But... I am also super curious how the SB20 works in an OB, so if you end up trying it let us know how it turned out 😏
Here's the same guy talking about just the Lii Fast-8's in the small Betsy baffles.
Note importantly ... on the floor placement is very important for small baffles to help the bass response.
I am curious how the SB20's would sound in the Betsy baffles and even more curious how they sound in the SLOB baffles.
Note importantly ... on the floor placement is very important for small baffles to help the bass response.
I am curious how the SB20's would sound in the Betsy baffles and even more curious how they sound in the SLOB baffles.
To be honest, IMO that guy's speaker demo recordings don't sound very good in general. I don't know if it's room effects, the baffles, the particular tube amps he's using, or what? I know this song by Chris Isaak very well and it sounds kinda cloudy/muffled and not very clear with exaggerated lower-mids/upper-bass. Or maybe the microphone he's using or microphone placement? The vids by @nandappe
using the SB20 MQWT sound much cleaner to me.
I know, you're thinking trying to compare the audio in Youtube videos is silly 😛
using the SB20 MQWT sound much cleaner to me.
I know, you're thinking trying to compare the audio in Youtube videos is silly 😛
I'd XO between 300 and 500, depending on the baffle you are using.
Any lower than that and the SB20 will struggle playing that low, and it will distort. Free it of playing too low and it will sing.
Here is an example of doing OB's the supposed "wrong way" and yet it still sounds good to me.
A lovely midrange and overall sound even though the small baffles are NOT on the floor.
The Lii Fast-8 drivers may be the reason why? Btw, this is a 1960's mono recording 🤔
I can't tell what electronics he's using with that turntable:
That said I think it might be improved by adding a good/fast sub and a pair of super-tweeters.
A lovely midrange and overall sound even though the small baffles are NOT on the floor.
The Lii Fast-8 drivers may be the reason why? Btw, this is a 1960's mono recording 🤔
I can't tell what electronics he's using with that turntable:
That said I think it might be improved by adding a good/fast sub and a pair of super-tweeters.
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