Is there interest in a large three way "monkey coffin" collaboration?

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

The Scan just seemed to catch my eye. I'm open to suggestions though. The Faital 6Fe100 and 6Fe200 are still options from the PE inventory that would work. Do you have any in mind?

Yes to the 15" Dayton. Is there no mid in PE inventory you like?

[djg]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Yes to the 15" Dayton. Is there no mid in PE inventory you like?

[andy19191]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Double post.

[andy19191]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I just lost my interest in this project!:(

Why?

[andy19191]

Re: Is there interest in a large three way "monkey coffin" collaboration?

2. I am going to switch to the ScanSpeak Discovery 15M4624G which is a solid 92.5 db 8 ohm driver with pretty smooth (mild wiggle around 1.5 to 3k) extended response and good power handling. The budget can perhaps sustain this driver's extra cost given the cheaper woofer.

You might need to check the sensitivity of the SS midrange which Voice Coil measured at around 90.5 dB sensitivity. If you can find some other measurements or, perhaps, determine that VC measurement conditions are significantly different to Scan's. I have been meaning to do this for a while since I have my eye on this mid for a narrow baffle tower.

[thekorvers]

Re: Is there interest in a large three way "monkey coffin" collaboration?

1. Switch to DC380-8 for the woofer. Lots of people seem to long for a 15" woofer in this project. The DC380 will do well in 100L sealed or in 131L vented with FB 22 it gives F3/F6/F10 of 30/24/19. In that box it will do handle 50 watts without exceeding excursion limits and peak output with that drive level is 107db which should be plenty.

[ATTACH=CONFIG]48317[/ATTACH]

2. I am going to switch to the ScanSpeak Discovery 15M4624G which is a solid 92.5 db 8 ohm driver with pretty smooth (mild wiggle around 1.5 to 3k) extended response and good power handling. The budget can perhaps sustain this driver's extra cost given the cheaper woofer.

3. The DX25 is still a very viable tweeter choice but I am leaning toward the SB26STCN which has adequate sensitivity and power handling and has received extremely positive attention lately from Jeff B among others.

4. The cabinet volume required should be very attainable with a 42" high box wide enough for the 15" woofer. The shorter version would be a pretty deep box if vented but wouldn't be at all bad if a builder wanted to go sealed.

I think I will order these parts tonight. Any thoughts or input?

I just lost my interest in this project!:(

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I still want to do something collaborative that will have broad appeal but we have lost the interest of many people with all of the back and forth on this thread. The ST305/Faital mid/DX25 design is really close to the "Rockin It Old School" design in the project showcase and I didn't realize that when I started this thread.

So in the interest of doing something cool with a retro vibe, broadly appealing and still within the original goals here is my revised plan.

1. Switch to DC380-8 for the woofer. Lots of people seem to long for a 15" woofer in this project. The DC380 will do well in 100L sealed or in 131L vented with FB 22 it gives F3/F6/F10 of 30/24/19. In that box it will do handle 50 watts without exceeding excursion limits and peak output with that drive level is 107db which should be plenty.



2. I am going to switch to the ScanSpeak Discovery 15M4624G which is a solid 92.5 db 8 ohm driver with pretty smooth (mild wiggle around 1.5 to 3k) extended response and good power handling. The budget can perhaps sustain this driver's extra cost given the cheaper woofer.

3. The DX25 is still a very viable tweeter choice but I am leaning toward the SB26STCN which has adequate sensitivity and power handling and has received extremely positive attention lately from Jeff B among others.

4. The cabinet volume required should be very attainable with a 42" high box wide enough for the 15" woofer. The shorter version would be a pretty deep box if vented but wouldn't be at all bad if a builder wanted to go sealed.

I think I will order these parts tonight. Any thoughts or input?

http://www.madisoundspeakerstore.com...5.25-midrange/

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Nice looking driver there. It would work really nicely for this design if it was available for purchase....

This new driver from Tymphany, Peerless Pro FSL-0615R02-08, is a stamped steel "silver" line and therefore hopefully around our price range. Only 100W but otherwise looks good. Does anyone know, or have a feel for, the price?

[andy19191]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Is that enough sensitivity from the mid or do we need to look for one with at least 92 to 93 db?

If the mid actually delivers 90dB and you have pulled the speakers out into the room your simulations suggest you might get it to work (but I haven't checked so that is not yes). There is some risk and placing the speakers, for example, against a wall on top of a sideboard would be a problem. A 92 to 93 dB midrange could be made to work in all locations but at the cost of some raggedness and padding down when the speaker is pulled out into the room. My preference is for the latter hence my continuing interest in other mids like the Peerless FSL.

If you want to do this you need to talk to Dave Pellegrene. Pretty much a different project altogether than the one being discussed in this thread. I think it is an awesome concept.

If the design works then this might be worth pursuing but the cost of the waveguides would push this project over budget. The budget monitor is currently pencilled in to have a mid and a tweeter in a small waveguide bolted flush to a square removable baffle. The more expensive monitor is intended to have waveguides CNCed into a stack of wood but I have not yet run simulations to work out the profiles.

Think big JBL reference monitor
https://www.jblpro.com/www/products/...series/lsr6332

So passive big monitors didn't become extinct years ago! Mind you an F3 of 54Hz, 4 ohms and a sensitivity of 93 dB is a bit discouraging.

[andy19191]

Re: Is there interest in a large three way "monkey coffin" collaboration?

This new driver from Tymphany, Peerless Pro FSL-0615R02-08, is a stamped steel "silver" line and therefore hopefully around our price range. Only 100W but otherwise looks good. Does anyone know, or have a feel for, the price?

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I understand. And it is a valuable suggestion.

Now does anyone know how to pull traced frd data from one of the dayton pdf's that are "secured".

I've read that any measurements below 100 Hz are invalid from one of the acoustics treatment sites. The factory measurements are, or should be, standardized in a relatively "infinite baffle". In some cases, I've seen measurements on a 9" baffle for smaller drivers. What I was suggesting was just to help get a start, before you buy drivers, not a final design.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Good to know about the response under 200 hz. I was just wondering if ngjockey's mention of a peak around 150 represented the Dayton measurements or a response based on the technique you mention below.

I would love to see you post a merged response like that for us. Baffle dimension currently under proposal is 42" tall and 15" wide.

You can stitch an actual box response below 200 hz with the response above 200 using Response Modeler in Excel. If you have box dimensions, I could do that for you if need be.

[ngjockey]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I've read that any measurements below 100 Hz are invalid from one of the acoustics treatment sites. The factory measurements are, or should be, standardized in a relatively "infinite baffle". In some cases, I've seen measurements on a 9" baffle for smaller drivers. What I was suggesting was just to help get a start, before you buy drivers, not a final design.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Understood. I wish there was an 8 ohm 15" with 8mm or so of xmax and the ability to do 30 hz or so in a vented box of say 130 liters or less. We could easily fit that kind of volume in this box by adding a little depth. Sadly the only woofers I know that exceed those criteria and have sensitivity over 90 db are AE TD series and the B&C 15BG100 both of which exceeed $300. I would even be more enthused about DC380 if it would work in a reasonable size vented box...but just for argument's sake here is the DC380 in 117L vented with Fb 21. It helps out with output and power handling down low below 50 hz. It doesn't look that bad actually. It gives the 107.5 db for 50 watts which is it's excursion limit. That is exactly the same output level the ST305 does in 100 liters with Fb of 30. The difference is the ST305 will handle 125 watts before it hits excursion limits putting it around 4 db better for max output.

I get what you are saying about the larger piston diameter having some degree of directivity to lower frequencies.

WBCD is JeffB's box simulator. He based it on Unibox. I have seen Jeff say it matches Unibox exactly FWIW.

Anyway here is the DC380 in the box mentioned above. What do we all think???

The larger surface area of the cone compliments the change from 4pi to 2pi space as it naturally has better directivity lower in frequency.......something you can't overcome with excursion.

As to the actual in box response as opposed to sims.....not sure if WBCD figures in coil inductance as Unibox does but the Le will greatly impact the overall efficiency given the limited passband of the woofer in a three way.

Don't get me wrong, I'm not completely opposed to the ST305.........it's just a case of big toys for big boys when foot stomping floorstanders are the mission! Lol

[JasonP]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I was going to trace the ST305 tonight but the .pdf is protected. Any way to get around those protected files and trace the .frd data from them?

Also, with using traced data for the LF isn't it a problem that the Dayton spec sheets state very clearly that the data below 200 hz isn't valid due to measurement technique.

You can stitch an actual box response below 200 hz with the response above 200 using Response Modeler in Excel. If you have box dimensions, I could do that for you if need be.