the beta need some boost in OB 6db as qts is low ,as Pa do....I made a q&d simulation in XSim (with an Eminence Beta 12" as woofer) and while the bottom would look good (incl. baffle loss in OB, but maybe I have to decrease the bass further), the upper region is still like a rollercoaster (okay, +/- 3-4dB around 92 dB).
Not that I would hear it
Maybe in slot load ? btw Pa have a jfet boost somewhere
I'm conservative
Yes, that's why I thought that I allow more bass with the xo and I will loose it on the baffle. Or do I still need the boost?
I took a look at the SB Bianco 12" and in the simulation it behaves better. I think I'll give it a try.
yeah the way I have always done it in the past is one "main" higher quality amp goes to the FR driver and then use a higher power/current amp (say a subwoofer type of plate amp) with low pass crossover+level adjustment for the bass drivers. This way you leave the major stereo signal untouched/corrupted and this makes it possible to use things like a flea watt tube amp, if you prefer, or really any of the many lowish powered class-D amps for the main amp.
Question if I may, how do you make different amps & sum them to sound like one ? Have never bi amp so Im curious.
If XO is below 100 hz pehaps less issues but what if XO is at 300-500hz would not different sound signature of the amps
create difficulties in intergrating ?
Thanks
nope the gain is that fr amp non see bass where the thd is... and in case of diy tube amp you can custum build better -smaller output iron for up100hz gain a lot more bandwith with just a smaller input caps for passive xo
my suggestion is buld a Nelson Pass amp no need tube M2 or J2 are wonderfull amp
My son and I made an open baffle set (out of curiosity) from these drivers before I make the 'proper' speakers next year. Baffle dimensions are 40cm x 100cm by 18mm thick using solid pine. We started building yesterday and by this morning had a pair of functioning speakers - they have been running in since then.
I'm impressed TBH - a lovely 'floating' sound with good stage depth,
clear midrange and the treble certainly isn't lacking. Bass is a little 'thin' but fortunately the Arcam A18 I am using them with has excellent (no downside) digital tone controls and a +3 out of 8 bass lift sorts out things nicely - will be interesting to see how the drivers settle over the coming weeks.
I'm impressed TBH - a lovely 'floating' sound with good stage depth,
clear midrange and the treble certainly isn't lacking. Bass is a little 'thin' but fortunately the Arcam A18 I am using them with has excellent (no downside) digital tone controls and a +3 out of 8 bass lift sorts out things nicely - will be interesting to see how the drivers settle over the coming weeks.
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Nice. Since this setup is temporary ... if... you're interested in experimenting I would cut them nearly in half and put the driver much closer to the floor and tilt them back say ~10 degrees. I think you'll get better bass response that way via floor/room effects. If it sound better you could use the cutoff pieces to glue on and double the baffle thickness which may help a bit too given this wood looks like low density and probably resonates some.
It's counter intuitive the have the driver NOT be closer to ear height - but reports are it really works better for OB's to have the driver closer to the floor.
Perhaps a seemingly cooky idea is to just lay the speakers on their sides and tilt them back somehow, if possible.
That might be TOO close to the floor and sound bad, but it's a no-effort and reversible experiment.
http://jelabsarch.blogspot.com/2012/06/open-baffle.html
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Thank you, actually its my enthusiast that was postphoned for around 25 years ago. Is there from Indonesian guy in here also?
another option would be to add some wings to them
Are you going to use them in the SLOB or what?
Are you going to use them in the SLOB or what?
Thanks for the info and ideas. I plan to add a frame at the back of the main panels which should stiffen the baffle up and hopefully reduce any resonance. I will experiment with putting the speakers on the sides to see what effect floor reinforcement has.
Incidentally I played about with REW a little bit last night and the bass actually has a bit of a lifT circa 50hz and the bass control on the Arcam adds to that area. The driver has an FS of 39.4 and bass certainly audibly drops off below 40hz when playing test tones. The strongest response seems to be between 250 - 500 hz with a gradual drop from there. All this is measured from my LP about 2m the speakers using the Spectrum app on an iPad to not the most accurate. The room is not ideal (small) but in this space the speakers seem to work best about 75cm from the front wall - FR smooths out and depth is better.