Dunlavy SC VII...Tribute..the one he should have made

[Gassman67]

Hello all, been running them for a few weeks now,quite smooth actually.I still need some more room treatments, thinking down the road aquiring a lyngdorf rp1 to smoothen out some room issues. I picked up a Dayton audio omni mic, 1st pic is sine wave at the listening position.

 

[darkmatter]

I'm a previous SC V owner, looking for a LITTLE more bottom end... So a friend ,Chris at Solen,and Neil from Wilmslow audio have come up with a 80x22x30 cabinet 4 way design . Twin JBL 2245 18",twin JBL 2118 8", ATC SM 75-150 and a Scanspeak 9900 in a classic Dunlavy design.the journey is well on it's way!

Very interesting, I have thought about what to do with my 4 JBL2245H bass drivers?

Now thinking again I would consider something similar using two JBLs per side low Q sealed ensclosure and together with 2 no 10" Volt BM2500.4 bass / mids again in a low Q sealed enclosure same alignment to match the above, 2 no Volt midrange domes and the top Seas exotic 34mm dome tweeter.

I would like to use 1st order crossovers throughout with compensation to make sure I could get as close to correct time alignmnet as possible. My enclosure would be similar in size around 80" x 21" x 34" overall.

This idea is one of about 6 or 7 I have been thinking about to supersede a big build I carried out and completed in my late 20s which was based upon the Wilson X1 Grand Slamm.

 

[Brett]

The 2118 requires a port.

Why?

 

[LineSource]

I have thought about what to do with my 4 JBL2245H bass drivers? QUOTE]

There is a construction thread on the AVSforum using two TD18HE woofers, with a SEOS-24 waveguide attached to the BMS 4594HE coaxial compression driver. Use a MiniDSP 2x4HD crossover with two amplifiers for simple woofer time alignment. The passive crossover for the BMS 4594HE is pretty good.

The MiniDSP can provide room equalization for sealed woofer bass, when using a high wattage amplifier.

The eJMLC-300 waveguide always makes me SMILE.

 

[Juhazi]

--- 1st pic is sine wave at the listening position.

Did you notice the peak before 0 time? It is the actual signal from the speaker, but a reflection is stronger in amplitude and program sets t=0 threre. Move the mic further from walls.

The response is really bass heavy, 150Hz blows 15dB more than 2000Hz. How does it sound? Is this from a single speaker or a pair? Take measurement always from just a single speaker. How about below 150Hz?

 

[pop4richard]

HI. Can I ask what crossover frequencies you choose?

 

[darkmatter]

Well it wouldn't have been as time coherent... that was the key point in all of his speakers.
I could understand porting the 15" bass but I wouldn't call this a true tribute.
I'm not trying to put you down or anything, just in the spirit of Dunlavy I'd have opted for time coherency.

Not even implying that you couldn't be on your way to an awesome speaker here...
Just not one that John Dunlavy would have chosen to design or build...

Send me a PM with your email address and I'll send you a copy of John Dunlavy's paper on "Loudspeaker Accuracy" to get an insight of his design philosophy's.
I found it online but can't trace it right now. I have a copy of it on HD. It's a series of jpegs of scanned papers.

Do you still have a copy of this paper?

Thanks

Simon

 

[wesayso]

Check your PM