Author Topic: OB: my plankie H8-15two  (Read 1897 times)

Online Chingy

Re: OB: my plankie H8-15two
« Reply #15 on: April 22, 2018, 10:03:03 AM »
Baffle is 540mm wide frame upright is 1200mm( im using 2 15inch per side ),  but the stand is universal, so you just mount your baffle, holes are made,  so just copy to yours
VA BW Pre, Tannoy Chevoits,Linn Kann, on Linn Stands,
Power trio (guitar, bass, and drums)

Online Chingy

Re: OB: my plankie H8-15two
« Reply #16 on: April 22, 2018, 10:18:59 AM »
Baffles can be anything, supawood, hardwoods, perspex even aluminium.
The base plate can be made for 10,12 or 15inch,  I'll make changes to the design and have slots, then you can adjust to your own widths
VA BW Pre, Tannoy Chevoits,Linn Kann, on Linn Stands,
Power trio (guitar, bass, and drums)

Online Chingy

Re: OB: my plankie H8-15two
« Reply #17 on: April 23, 2018, 09:30:43 AM »
just i update, amplification and pre amp was collected yesterday, Vatiros Hydra pre and Rotel  RB-985,
still need to play with how the 5 channels will power the speakers ?

the pre has 2 pairs of pre outs , BI-AMPING connection is a option, use the left and right channel for the Low freq and the Surround left and right for the Hi freq, and the centre will not be used

also i'm collection the baffles, supawood on Wednesday/Thursday, to do some work the long weekend
« Last Edit: April 23, 2018, 09:43:56 AM by Chingy »
VA BW Pre, Tannoy Chevoits,Linn Kann, on Linn Stands,
Power trio (guitar, bass, and drums)

Online Chingy

Re: OB: my plankie H8-15two
« Reply #18 on: April 23, 2018, 09:51:41 AM »
update also to the frames,

10 and 12 inch drivers also a option, just your base plate will change, but i'll need details on you're baffle size

see pictures of 10 and 12 inch options


/\ 10 inch options, driver you can use, or what you have


simple one piece baffle

Also with the kit, I'll supply the mounting feet, simular to these

VA BW Pre, Tannoy Chevoits,Linn Kann, on Linn Stands,
Power trio (guitar, bass, and drums)

Offline Mongoose

Re: OB: my plankie H8-15two
« Reply #19 on: April 23, 2018, 09:57:10 AM »
STOP IT! BE GONE DEMON! TAKE YOUR IDEAS AND BE GONE! ITS CONTAGIOUS!  :ROFLMAO:

Cant wait to see the final result. Looks good  :thumbs:

Online Chingy

Re: OB: my plankie H8-15two
« Reply #20 on: April 23, 2018, 10:03:26 AM »
just because i can


just need a good spray painter..
« Last Edit: April 23, 2018, 10:23:06 AM by Chingy »
VA BW Pre, Tannoy Chevoits,Linn Kann, on Linn Stands,
Power trio (guitar, bass, and drums)

Online Chingy

Re: OB: my plankie H8-15two
« Reply #21 on: April 23, 2018, 10:19:52 AM »
my frame design come from this,



you can also make your own frames, very easy to get this



happy to share the drawings, pm me, you can make your own, i don't mind at all
« Last Edit: April 23, 2018, 10:27:12 AM by Chingy »
VA BW Pre, Tannoy Chevoits,Linn Kann, on Linn Stands,
Power trio (guitar, bass, and drums)

Offline vinyljan

Re: OB: my plankie H8-15two
« Reply #22 on: April 28, 2018, 01:21:40 PM »
The Daan Jacobs topic convinced me, took these out of storage.  Time to learn about crossovers etc :thinking:



So the woofers will be 10 inch but not open baffle, either closed box as the originals or bass reflex like "Clarion by SEAS".  Adding cab volume/height to experiment with is easy due to the separate baffles.


10 and 12 inch drivers also a option, just your base plate will change, but i'll need details on you're baffle size ...

Also with the kit, I'll supply the mounting feet, simular to these



Like the "feet" and bamboo baffle :whistler:
In a maximum bank turn in a normal category airplane, like a typical Cessna, everything is fine until you turn across your own wake

Offline Kemosabe

Re: OB: my plankie H8-15two
« Reply #23 on: April 30, 2018, 07:32:35 AM »
Is everyone who's building an OB speaker here aware of how power hungry they are? I was going to build a pair myself till I heard 250w of Krell power (which is the official power - actual is more like 380w) being swallowed up by a set of OBs. Said person is now using power in the 600w to 700w range. Maybe if you don't ever want any real volume at all and are content with what would be very low volumes to me then maybe 200w will do for late night jazz and Michael Bubble.
DIY hi-fi: the journey is the destination.

Offline King_Julian_S

Re: OB: my plankie H8-15two
« Reply #24 on: April 30, 2018, 08:36:26 AM »
Then you must be using inefficient or inappropriate speakers  drivers sire... what efficiency and QTS are those etc ?

Ofcourse they have less bass and a tad less Loud sounding but the OB in itself does not make it power hungry per se ..

Again a balance .. will take the lesser SPL and open sound anytime over the boxy sound of a reflex if all else is equal ...

Anyway used a 300b in the past with various 12” of upper 90 efficiencies and there was no lack of power there .. could actually reach much louder then my vivid 1.5 with kt88’s ... but the baffle was about 1m wide and the untreated room just wouldn’t allow that kinda loudness( be it open baffle or bass reflex etc... )

Actually the axiom 201 compared to the ones Chris had in the boxes was not far off... by a totally different sound though .. nothing boomy in the LF just like the vivid used to play the bass etc.. mids was much nicer .. but being a fullrange 12” whizzer the tops was a bit sharp with some music indeed and if I knew how to fix that they’d still be playing ..
the Philips 12” with 300b replaced my Bowers cdm7’s with the McIntosh at the time and there was no degradation in terms of max volume the room would allow .. both could not be set to full volume or even close.

So I disagree that with such efficient drivers they’ve had to go crazy watts for a room in the 100 sqm range ... ofcourse like many other decent hifi speakers you would not want to party like a 15” PRO EV etc.. but indoor parties my OB’s certainly did and with volume less then 12 O’clock

Just BTW my current Yamaha ears go loud enough with the 2a3( what’s that 5 Watts or less )  .. again not party loud but more then enormous FB for home use .. I rarely put them at full volume unless testing( again the room )...
I am not sure what will happen if I had to throw 500 Watts etc at this Yamaha’s ?
Will most probably crack some glass and or pop the speaker whichever comes first..




Non audiophile music lover...

Offline King_Julian_S

Re: OB: my plankie H8-15two
« Reply #25 on: April 30, 2018, 08:37:03 AM »
What amps and wattage etc was Rudy using with his set ? Maybe he can advise ..

Non audiophile music lover...

Offline King_Julian_S

OB: my plankie H8-15two
« Reply #26 on: April 30, 2018, 08:44:38 AM »
just BTW my yammie measures about 110 DB average with the 2a3 (cell phone measure at about 3m distance) .. and I listen averagely only at about 80 in the 100sqm room.. perhaps even less most of the time.

Look if you really listen to 300db or that much watts all the time then I think any system and room would be a challenge .. then u really would have to fork out for special treatment and stuff ...
« Last Edit: April 30, 2018, 08:55:09 AM by King_Julian_S »
Non audiophile music lover...

Offline Kemosabe

Re: OB: my plankie H8-15two
« Reply #27 on: April 30, 2018, 09:55:41 AM »
Check with Jim gore. His drivers are highly efficient top of the line beyma etc. Nothing but the best and nothing inappropriate about it. I also didn't realise this but the OB design eats power. We were sitting listening at fairly high but not uncomfortable levels and I was surprised to discover that the krells were maxed out. Not an ampere more to give. Now with 600w on tap there was more control and headroom. Based on what I've seen I wouldn't apply for this design on the basis of using a multi channel av amp rated at 100w pc or something in that ballpark.
DIY hi-fi: the journey is the destination.

Offline Wolla

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Re: OB: my plankie H8-15two
« Reply #28 on: April 30, 2018, 10:01:24 AM »
I use flea-power and have plenty to spare:
https://youtu.be/KDp0prrZMW8
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Offline King_Julian_S

Re: OB: my plankie H8-15two
« Reply #29 on: April 30, 2018, 10:05:53 AM »
But those are the thinner taller baffles right ? What was the width ?

Perhaps that’s the problem .. don’t know why you experienced that .. perhaps you do expect 300db ..
perhaps something about those Beyma drivers ..

Can only guess ..

I have tried other types but in general I think the advise from jelabs that width and flush against the ground still worked best for me .. ofcourse I wouldn’t mind a Rudy or Jim gore look alike ..

I wonder why that happened though .. 600 Krell Watts is plenty man ..


Non audiophile music lover...