A***, suddenly realised that I had forgotten to take the baffle thickness into account with my sims. So re-ran the calculations with an extra 60mm effective baffle width. suddenly not as flat. 2 drivers again becomes optimal. Knew it was going too well. Not sure how to best flatten that, notch around 300Hz or shelf at 700 yet.
And some pics for your delectation.
First one shows the woofer. Yes I know it needs a clean
Second shows I can't operate the flash on my camera, but gives you an idea how constrictive the std grille is. Memsahib is adamant that grilles must be in place when not in use, so will drill out the retaining holes and use velcro or magnets for quick removal
third shows how stuffed the cabinet is. No science there.
And last one shows what the poor driver has to work with. No chamfering of the baffle to help airflow and it's up against the side of the box on 3 sides. I will do some work on that before the new ribbons arrive.
And some pics for your delectation.
First one shows the woofer. Yes I know it needs a clean
Second shows I can't operate the flash on my camera, but gives you an idea how constrictive the std grille is. Memsahib is adamant that grilles must be in place when not in use, so will drill out the retaining holes and use velcro or magnets for quick removal
third shows how stuffed the cabinet is. No science there.
And last one shows what the poor driver has to work with. No chamfering of the baffle to help airflow and it's up against the side of the box on 3 sides. I will do some work on that before the new ribbons arrive.
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Hi Bill, Could I see a pic of the speaker with no grill on it, never seen hybrid pics.
Thanks Al
Thanks Al
here you go.
Before anyone claims abuse of speakers, note that they have been in storage (AKA kitchen) for 10 months and had a small accident, hence the filthy grille. The missing bit from the Left hand one was my dear middle daughter knocking it over about 13 years ago. It hit the cd rack on the way down.
I think they actually look better without the grilles on. SWMBO differs in that opinion...
Before anyone claims abuse of speakers, note that they have been in storage (AKA kitchen) for 10 months and had a small accident, hence the filthy grille. The missing bit from the Left hand one was my dear middle daughter knocking it over about 13 years ago. It hit the cd rack on the way down.
I think they actually look better without the grilles on. SWMBO differs in that opinion...
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Davey...
I don't consider the thread hijacked at all. Far from it - I have gathered a lot of ideas from the various commentaries.
Once I get over my head cold, I plan to assemble my Centaur ribbon and single Peerless nomex woofer on a re modified home made OB 14" wide. Minidsp will be used crossed at 500hz LR4 for starters. Tuning is by ear, my RadioShack spl meter and test tones cd. Each OB will straddle a Ripole sub which will have it's own plate amp per channel.
My makeshift assemblies so far have yielded good results. Hope I can put it all together in a neat package.
Thanks for all the good ideas.
Peter
I don't consider the thread hijacked at all. Far from it - I have gathered a lot of ideas from the various commentaries.
Once I get over my head cold, I plan to assemble my Centaur ribbon and single Peerless nomex woofer on a re modified home made OB 14" wide. Minidsp will be used crossed at 500hz LR4 for starters. Tuning is by ear, my RadioShack spl meter and test tones cd. Each OB will straddle a Ripole sub which will have it's own plate amp per channel.
My makeshift assemblies so far have yielded good results. Hope I can put it all together in a neat package.
Thanks for all the good ideas.
Peter
...suddenly not as flat.....
Is it a bad thing? One of the few interesting recent innovations is loading a dome tweeter in a shallow horn to achieve the same low end response boost shown in your sim. It suggests the tweeter can be crossed a little lower and still stay in its safe operating area. I wonder if it was Bloom's intent.
Bill, Whats the resistance of that 40" MRT with no wires attached to it?
Thanks Al
It's only 26" in this, and currently somewhere around a few MOhm. New ribbons will be measured, expecting them to be much the same as stock (3.5-3.7)
Is it a bad thing? One of the few interesting recent innovations is loading a dome tweeter in a shallow horn to achieve the same low end response boost shown in your sim. It suggests the tweeter can be crossed a little lower and still stay in its safe operating area. I wonder if it was Bloom's intent.
I'm only showing the woofer response in that SIM. With a thin baffle it would have been nicely flat to 200Hz. I need to get 150Hz LR2 HP and 700Hz LR4 LP out of that. If the driver has a falling response there I might be ok...
ref tweeter waveguides, I do wonder if something similar could be done on the apogee ribbons. there are waveguides for smaller ribbons such as Horns but design or fabrication are beyond my capabilities 🙁
Edit: just checked and the seos horn is 10.5" wide at the mouth. that would make for a funky looking apogee...
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Bill, would you say it safe to hook an amp direct to the ribbon, say 500hz up? Like to see how it sounds with no passive network mudding up the transparency.
Thanks Al
Thanks Al
Well I just ran my 26" stage ribbon active 500hz 24lr , the vocals were cyrstal clear on low side, the passives have got to go. it seems no matter what caps you use, they muddle the sound.
DeltaStar...
I agree with you re the passive network. I wouldn't dream of going back to them.
When I first toyed with active, I used Rod Elliot's boards crossing at 500hz. No big deal.
But, with the minidsp, amazing convenience to try all sorts of slopes, plus the ability to dramitacally reduce the room modes with EQ. Though I find with the OB arrangement, room modes are considerably less anyway.
All good suff.
Peter
I agree with you re the passive network. I wouldn't dream of going back to them.
When I first toyed with active, I used Rod Elliot's boards crossing at 500hz. No big deal.
But, with the minidsp, amazing convenience to try all sorts of slopes, plus the ability to dramitacally reduce the room modes with EQ. Though I find with the OB arrangement, room modes are considerably less anyway.
All good suff.
Peter
Hmm, just mulling. I intend to build an analogue line level crossover, but I am wondering if a minidsp 2x4 isn't a no brainer in order to find out what I need to do. The HD versions are too expensive, but not spending $80 seems a very false economy, esp as always useful to have for bass equalisation down then line.
The other advantage is that it allows me to go OB 4 months earlier than originally planned 🙂
Also does anyone have any experience with the mini-DSP microphone. Need to get a calibrated mic anyway...
The other advantage is that it allows me to go OB 4 months earlier than originally planned 🙂
Also does anyone have any experience with the mini-DSP microphone. Need to get a calibrated mic anyway...
This post is just to add info that some may not have seen....
Centaur or the Minors.... NEVER had two pr of binging post on ea speaker,setup for bi-wireing or bi-amping.......Only the Magors came with this setup....
The Centaur crossover Schematic that for years has been on the Apogee Speaker user web site...an post around as Dave pointout in 02 is Not Right!
In the Schematic at the pos input to the Mid/high.....the coils input is in front of the 70mf cap input....this needs to be moved.... as seen in crossover pic of the Stock centaur ....
To the other side of the of the 70mf an input to the 10mf an 1.5 res....
Then the Coil valus may be off.... but all then looks right ?....
Othere well point out my falings...
But now we can see that MT crossover in the centaur is vary close to the Stages......an the MT in the Minors crossover much higher....
Thanks for Any An all info on Apogee speakers..
http://www.apogeespeakers.com/projectstech/centaur_minor_crossover.pdf
Centaur or the Minors.... NEVER had two pr of binging post on ea speaker,setup for bi-wireing or bi-amping.......Only the Magors came with this setup....
The Centaur crossover Schematic that for years has been on the Apogee Speaker user web site...an post around as Dave pointout in 02 is Not Right!
In the Schematic at the pos input to the Mid/high.....the coils input is in front of the 70mf cap input....this needs to be moved.... as seen in crossover pic of the Stock centaur ....
To the other side of the of the 70mf an input to the 10mf an 1.5 res....
Then the Coil valus may be off.... but all then looks right ?....
Othere well point out my falings...
But now we can see that MT crossover in the centaur is vary close to the Stages......an the MT in the Minors crossover much higher....
Thanks for Any An all info on Apogee speakers..
http://www.apogeespeakers.com/projectstech/centaur_minor_crossover.pdf
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I've just realised that I can fit the amps into the speakers. some packaging to work out, but this could end up quite a neat active package 🙂
I installed my Symasym amps in the stands. See post #5.
But now I will have the subwoofers in that location. I plan to build some D class amps to play with and they are quite compact and should fit in with the subs somehow. Though, I have no idea how they will compare to the Symasyms.
Peter
But now I will have the subwoofers in that location. I plan to build some D class amps to play with and they are quite compact and should fit in with the subs somehow. Though, I have no idea how they will compare to the Symasyms.
Peter
I'm only showing the woofer response in that SIM. .... I do wonder if something similar could be done on the apogee ribbons.....
Do the sims show similar augmentation for the ribbon's location?
A set back waveguide large enough to provide meaningful gain in the xover region might also create the offset required to time align a dynamic woofer. Might make for a killer setup.
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