"Fundamentals" for a new stand mounted speaker project -what goes around comes around

[JonMarsh]

Yeah, that's the truth, but then in 10 they walked back some of those changes, or I'd have stayed with 7. So far, so dood; some thing annoy, like the startup menu, and all the useless (to me) new clutter, not being able to configure it readily, still haven't found a way to increase the number of ptorams listed tin the main start up menu and pin the ones I want, but I suppose I'll get there. Some things, like the snipping utility, are harder to find.

At least all the programs seem to still run, and I'm setting up El Capitan updating one of the other drives so I can get the Windows 10 Bootcamp drivers.

[ergo]

For Win 10 start menu... if you open the list of Apps you can right click and "Pin to Start" to get them to start menu. There you can drag and drop and sort them and also make category names. You can also right click again on each icon and make it smaller - then you can fit many more.
For things like Snip it's usually easier to click the Win key and start typing sni... and it's gonna pop up with global search very fast (first times it can take a slight moment as the system seems to need a bit of time to create the fast indexes.

I'm now getting used to the 10 and I did also upgrade my home PC about a month ago. This far all the hobby tools work (LspCad, CLIO, ARTA, HolmImpulse, various CAM tools cad tools too). I was expecting less luck actually and made efforts and left Win 7 as a dual boot option in case something does not want to play with 10 - but as said so far so good.

***
On a project note - I did order the woofers and PR-s also and from a local Estonian reseller! That is a very different experience and very nice development of things. Some 3..4 years ago only option was to get drivers from Netherlands or Germany and before we joined EU I would often order those from US (paying like 30% extra on shipping) as Europe orders were also going to customs and price wise same or even more expensive.

[sfdoddsy]

For those considering the C18, i finally got a chance to do some extended listening today, even though the crossovers are by no means ideal. I was able to flick between it and the Maggie MC1, then trot downstairs to listen to my main speakers which have the BG Neo10 and Neo3 and Peerless SLS 10 in a tapering LX521/Note style open baffle.

It's quite fascinating.

The C18 sounds the same wherever I sit, flop, recline or otherwise drape myself. Except from behind.

The Maggies have a tiny locked in spot where they sound good, and even there don't sound as good as the C18s.

The Neo10/3 system is much more forgiving than the Maggies for listening position. They are actually as good as my Orions were in that sense. But there is still an improvement when you sit up properly. Or in the middle.

At their best, they sound better than the C18s. I assume it is because they use great drivers and are dipole way up high. I like the faux-airiness of true dipoles. They match my old Apogee Duettas for sheer enjoyment.

But I don't listen to them in the best position. I sprawl. My head is way below the tweeter. And way to one side. So I don't take advantage of their excellence.

The C18s are forgiveness incarnate, whilst still sounding great. The room they are going in is a living area rather than the dedicated room downstairs. My partner and guests deserve decent sound. So do I when lying horizontal, sideways, or when being squished by my three year old.

The C18s sound like more like my Orions than my Neos, but everywhere. This is remarkable with the tweeters being about 6 feet up. The soundstage is odd that high, but not unlike sitting in the front row of a gig with the orchestra on the stage above you.

Great for movies too.

Given the price of the C18, i think you could get as good or better sound if you can listen close to the horizontal and vertical axis. But if you can't or won't, they really do work as advertised.

[JonMarsh]

The C18 sounds the same wherever I sit, flop, recline or otherwise drape myself. Except from behind.


The C18s are forgiveness incarnate, whilst still sounding great. The room they are going in is a living area rather than the dedicated room downstairs. My partner and guests deserve decent sound. So do I when lying horizontal, sideways, or when being squished by my three year old.

The C18s sound like more like my Orions than my Neos, but everywhere. This is remarkable with the tweeters being about 6 feet up. The soundstage is odd that high, but not unlike sitting in the front row of a gig with the orchestra on the stage above you.

Great for movies too.

Given the price of the C18, i think you could get as good or better sound if you can listen close to the horizontal and vertical axis. But if you can't or won't, they really do work as advertised.

This mirrors my own limited listening experience, and is why I'm eager to get the first example done, and frustrated that things keep coming up to suck up my available spare time that are not optional or really in my control. I think this small cabinet "Model One" will be very interesting within the size context, and the need to be able to readily take it places, like to work!

I should have the inductors for the new build for the tweeter crossover by the end of the week, but this weekend and the next several ones are already committed to other things that have come up having nothing to do with audio! I may even need to schedule a week off to cope with this particular matter.

I do envision creating a center channel with the C18EN001, too- the only real question is how serious or massive do I need to go with the low end? Probably no PR's, just a flanking pair of SW223BD02 wired in series? Sort of the answer to the whole Ardent Center channel issue...

[sfdoddsy]

Yes. I've not owned a coax before so I don't know if this is common to the breed or special about this one.

I forget to mention the only obvious downside, and depending on your desire for accuracy over euphony it may not be a major one.

The C18 doesn't have that airy 'sparkle' that the Maggies and my Neos have.

I assume this is because it isn't dipole once the tweeter kicks in.

For those familiar with Orions, it's like the difference between the original version and when SL added the rear tweeters.

I like that sparkly effect, but again you only really get it when your head is in just the right position. So I'm OK with losing that occasional pleasure in return for not losing the treble and imaging once my ears leave the sweet zone.

[JonMarsh]

It is my belief that there are tradeoffs in all available configurations... part of why I continue to experiment is to get first hand knowledge of those trade-offs, and figure out what is really most important to me. That's why there are also two line array projects sitting in the wings for when I can give them some attention....

Now, just like the Orions use a rear firing tweeter, I'm sure that's possible to implement with these, too, but making it really integrate with the back wave in your dipole might be a little tricky. Doing a cost/benefit analysis isn't easy, as you can imagine.

[sfdoddsy]

I now have both speakers hooked up properly, with the Minidsp in the chain so crossovers and EQ are working as they should. I'm crossing from the coax at 350. The Rs225 is much less sensitive so I've had to cut the coax a lot. If I do a final version, i'll go with twin paralleled 8 inch woofers to raise sensitivity rather than a single 8 or 10.

With two speakers running, they continue to sound very good. Certainly better than the Maggies, and much better than the Martin-Logan Frescos I had in the same spot. The Frescos use BG Neo8s and Neo3s, but in a box. It's amazing the difference removing said box makes.

The only real issues, compulsive tweaking aside, is the non-dipole radiation when the tweeters kick in I mentioned above (compared to my downstairs system). The speakers are actually in the middle of the room with kitchen and dining behind them, and the treble roll-off there is blatant. There is also the weirdness of having the speakers so high. The acoustic center is about 6 feet in the air.

It's cool for movies, but for music is like sitting front row looking up at a raised stage. I get an aural crick in my neck.

I'm pondering reconfiguring everything and moving the Neos upstairs on a panel which will fold flat against the wall (where the Maggies are now) so they can be lower and fire front and back, and then put the Seas downstairs in a tapering baffle with the Peerless SLS10.

If I move the Neos up, I may try a DIY version of the Lyngdorf DP1 system using boundary woofers up to the Neo10. I have two small sealed wall-mounting 'subs' that might work.

Ah, the joys of DIY choice.

[csmielke]

Bass Enclosures

Jon,
The sawdust was flying late last week on what for me is a new subwoofer but for you could represent bass bins with the SDX10 and two SS 26W PRS. I built it to what I modeled at 47.6L net. close to some of the models you did. The size is not that scary 21" Deep by 15.5" high and 14" wide. Your coax box could readily sit on top. Here are some pictures of the progress (excuse the lack of photography skills. I will keep you posted on how it all turns out and sounds. Hope my attachments work?
Chris

[5th element]

Nice work there.

[csmielke]

Thanks Matt, been a while since I did this. Maybe tomorrow I can start gluing it up.
Chris

[kevinm]

Hey Chris,

Do you plan on any bracing?

[csmielke]

Kevin,
I do, for the top and bottom I am going to install 1/2"X2" red oak bracing in an x fashion similar to what they do for acoustic guitar tops. This gives the most bracing in the middle of the panel. I will do something similar on the sides in front of the passive radiators. The front and back are both an inch and a half thick so not planning anything there. Oak seemed like a stiff enough material. I have not seen anyone do the X bracing in any prior projects so I thought I would give it a try. I hope that's enough, any thoughts?
Chris

[JonMarsh]

Cool, making some progress there!

I got the new crossover parts in, but marketing and technical management (of other people, not me) came to me Friday to review an engineer's project (who is out on medical leave for three weeks post surgery) wondering if it was ready for PCB layout (it's not, not remotely) and doing a design review/with design start over all weekend. This is getting tiresome... l made a ton of progress, (seems like I can do a weeks worth of work in a weekend when I don't have interruptions and email to deal with) and met with the engineer at his home for three hours yesterday to go over stuff and see if he had anything besides the partial schematic file he'd sent by email on Friday. It was a productive meeting, and now today I meet with the marketing guy and the Engineer's boss to explain what's going on, now that I've done their job for them...

So, no test yet of the tweeter crossover update- I'm booked with doing a domestic move finally starting next Saturday over the next two weeks- will be good to have that out of the way, but no speaker building while that is going on!

So, I'm enjoying reading about what you guys are doing when I have my morning breakfast and latte!

[TEK]

Hang in there Jon...
Can't be that long until you can retire and spend all of you time doing design work for us instead of your workplace :P

[JonMarsh]

Hang in there Jon...
Can't be that long until you can retire and spend all of you time doing design work for us instead of your workplace :P

I'm looking forward to it, too... and they're aware they're walking a narrow line, because at anytime I could just say, screw it....

I'm just a big greedy, though, and want to make a little more hay while the sun shines...

[ergo]

Proof attached that the units have now all arrived... Will start planning the box build now

[JonMarsh]

Glad to see your progress and that the enclosure design stuff is getting sorted out. It's going to be at least two weeks, maybe 3 or more before I have time to get back to any Audio stuff, but getting these going is a priority. For now, it's all about finishing the move out from my old place by Nov. 29.

BTW, with regards to the cabinet design, there are also (on mine) going to be side panels with 45 degree beveled top and front, but probably flush flat back and bottom added on; these are cut from LBL panels which have been edge glued from 12" wide by 3/4" thick boards. the top and bottom will use follower router bits to follow the curves in the top and bottom front edge. This has been in my mental picture from the beginning, (preparing those panels was the first actual work I did on the cabinets) but drawings haven't been updated yet.

As mentioned in the PM, I will likely re-create the drawing in my solid modeling program, Shark FX. It has quite a bit better 3D too 2D tools. Of course, it should - it costs more than Sketchup Pro, too!

Image not available

[sfdoddsy]

Just a wee update on my C18 experimentation.

After some time living with the earlier setup, I became a little dissatisfied with what the RS225 was adding to the party. No matter what kind of EQ I tried it just sounded a little thin in the mid-bass.

I also couldn't handle the speakers up so high.

So I'm trying out something I've been meaning to for a while.

It's a DIY coax version of the Lyngdorf DP1.

The C18s are running OB, and I have a pair of on-wall 'boundary' woofers positioned on my step running from 300hz down.

The woofers in question are cheap-as Pinnacle SlimSubs I bought on eBay for $300 the pair. Each is has two 6.5s in a small sealed box. They get massive amounts of EQ to get them flat down low, but I cross at 40Hz to a proper sub.

Not sure if this kind of thing is a keeper yet, but it has solved the mid-bass problem.

[JonMarsh]

Makes some sense- with your setup, being purist about dipole or monopole may not make much sense, and this kind of configuration will cetainly make the midbass and low midrange easier to cope with. :T

[csmielke]

Jon,
I've been out of pocket for a couple of weeks on a duck hunting trip to N Dakota. Finally got back on the enclosure gluing it up and putting a couple of coats of lacquer in preparation for the psa backed quarter sawn walnut veneer. More updates to come on that. On another topic, has anyone tried the Pono music player? I picked one up on my trip back passing through Chicago. I added some balanced "Surf Cables" and connected it up to my Classe CP35 preamp which I added back into the rack for this purpose (only thing I had with balanced inputs). All I can say is I now understand why John Atkinson has it as a provisional class "A" rating in Stereophile. What a great sounding player and for the money it hits it out of the park. If anyone else has any experience with it please share.
Thanks
Chris

[csmielke]

Missing images

Sorry, did something wrong inserting images.
Chris

[DS-21]

It's a DIY coax version of the Lyngdorf DP1.

The C18s are running OB, and I have a pair of on-wall 'boundary' woofers positioned on my step running from 300hz down. ***
Not sure if this kind of thing is a keeper yet, but it has solved the mid-bass problem.

Very interesting! How's the image placement? Does anything localize at the bass bins?

[sfdoddsy]

If you mean regarding image height, the qualified answer is no. Qualified in the sense that I'm still getting used to the difference of not having the main panels way above my head as they were before. It certainly sounds a lot more natural now.

The C18s are around 1100mm off the floor, which by my calculations is just within the limit for centre to centre spacing using a 300Hz crossover.

[sfdoddsy]

Makes some sense- with your setup, being purist about dipole or monopole may not make much sense, and this kind of configuration will cetainly make the midbass and low midrange easier to cope with. :T

The full dipole bass of my main speakers sounds a bit better to my ears, but then again I'm not how they would go jammed against a side wall.

[sfdoddsy]

OK, shootout time.

[ergo]

I've finally far enough that I have a listening room ready .... speakers to go in it are planned to be the Isiris Monitor type project.
Now planning the box build....

Jon the way you have planned the box does not work for me in this room... so I spent some time today to figure out different proportions. I need to place the speakers close to the back wall and with the original depth of the box (Sketchup ver)it is too deep.

I tried to keep the mid and low box volumes very similar as well as the mid/woofer spacing.
The low frame on bottom would house the crossover.

I do expect that I need to tweak the crossover somewhat to tune it for these changes in box, but I do have all the measurement tools as well as LspCad to do that.

Now Jon - I would have a question... would you have a gut feeling if placing the PR on back would be better at same height as the woofer or would it perhaps be good to move it lower as box is now taller. Latter would maybe spread the source of LF vertically and improve the room interaction? Other option would be to place the PR on the inner or outer sides instead, but that would of course deviate from original design even more.

[JonMarsh]

If you do it tall like this, and if you plan to have the enclosures fairly close to the wall, the best place would be at the boundary intersection, so moving the PR near the floor makes good sense.

BTW, the version I am building is meant to be on a stand, or an additional sub enclosure.

This is my first normal weekend since early June, (that is, not working on work work or some other mandatory set of tasks like moving out of where I lived for 23 years) so these activities should/will be getting more focus this month! Today I hope to combine updating the test crossover for the tweeter for this project, while listening to the Benchmark AHB2 amplifiers which I'm delivering this week to my colleague from Munich while he's visiting. I suspect I'm going to miss them, they sound much the way they measure, very very clean.

[ergo]

Thanks for reply
I have a "NAD C 390DD Direct Digital Powered DAC Amplifier" waiting for the completion of this project. As I needed the whole signal chain basically to this room I ended up buying C390DD as almost a one box solution that still has got good feedback from many. I'll finish the speakers and give this a shot and then gradually see if and where to go with upgrade path.

I know well how much steam it takes to move house. We are now in this renovated house for 2 years, but it was only about 60% done when we moved in. Garage renovation is still on todo list and basement workshop needs setting up and tweaking too. In this climate the winter time is not really optimal for speaker build as I don't have a big enough 'heated workspace' to work in. But I will get it done somehow.

[TEK]

For a bit over 3 and 1/2 year ago this was where we live now:



And almost exactly 3 years ago this was it.


Both pictures was taken from almost the exact same point. The garage have been moved closer and to the left of where I stand when taking the picture.

Moved into the new house 21. December 2012.

Fixing old houses has a lot of charm, and if you are into that, might be really giving work and may give great result.
But I have to say that I feel very lucky that we had the opportunity to get a new house build.

So(, as long as my speakers WAF factor is high enough :roll, I plan at least plan on staing put right where I am for a long, long time :B

[csmielke]

Jon,
Finally finished the bass bin (for me sub). Completed the veneering last week(quarter sawn walnut). It turned out better than I hoped as it's been 25 years since I attempted veneering a cabinet (Tabor design from the late 70s). As you build yours make sure bracing is sufficient. I went back into the cabinet and added 6 oak doles and pads to further brace the cabinet (now net volume of 44-45L). If I did it again I would make all walls a double thickness of 3/4" Baltic birch instead of just the front and back. Spent time the last day dialing in the crossover and levels and I am very pleased with the results. The simulation is delivering as I thought it would and I now need to add some type of felt pads under pictures on the wall to keep them from vibrating. I listened to James Taylor's Hourglass (Gaia) and Dave Grusin Migration as well as the opening of Pink Floyd Dark Side of the Moon. I am going to pull out some Bach Toccata & Fugue next to see how it delivers. I can't imagine the view you shared of four of these (two per side). You and Steve need to be careful as you might trigger a seismic event when you crank them up!
Chris

[kevinm]

Wow! That is beautiful veneer Chris! What was your finishing process?

[csmielke]

Kevin,
Thanks, started by sanding the veneer with 220 grit. Then just three coats of General Finishes water based high performance topcoat (satin) with a rub down with 3m finishing pad between coats. I put a coat of paste wax at the end probably not needed. The general finishes top coat was sprayed on and was really easy to use. Clean up was the easiest I have ever experienced ( a little soap and warm water shot through the sprayer and air dry). I don't think I will use anything else in the future. I forgot to mention it was a 3m psa backed veneer, also easy to use.
Chris

[JonMarsh]

[ATTACH=CONFIG]24891[/ATTACH][ATTACH=CONFIG]24892[/ATTACH][ATTACH=CONFIG]24893[/ATTACH]
Jon,
Finally finished the bass bin (for me sub). Completed the veneering last week(quarter sawn walnut). It turned out better than I hoped as it's been 25 years since I attempted veneering a cabinet (Tabor design from the late 70s). As you build yours make sure bracing is sufficient. I went back into the cabinet and added 6 oak doles and pads to further brace the cabinet (now net volume of 44-45L). If I did it again I would make all walls a double thickness of 3/4" Baltic birch instead of just the front and back. Spent time the last day dialing in the crossover and levels and I am very pleased with the results. The simulation is delivering as I thought it would and I now need to add some type of felt pads under pictures on the wall to keep them from vibrating. I listened to James Taylor's Hourglass (Gaia) and Dave Grusin Migration as well as the opening of Pink Floyd Dark Side of the Moon. I am going to pull out some Bach Toccata & Fugue next to see how it delivers. I can't imagine the view you shared of four of these (two per side). You and Steve need to be careful as you might trigger a seismic event when you crank them up!
Chris

Looking very nice! :T

I have a fondness for good quarter sawn Walnut; I did several systems with that in the 70's. It seems harder to get really nice figured walnut veneer these days, but yours looks very good.

I'm still digging out from a backlog of "normal" weekend chores, but also will be working on the test crossover this afternoon- gotta get some time in for audio, and hope to improve that as the month goes on!

[csmielke]

Great to have you back at it. Having moved a number of times for business I know how stressful and tiring it can be. I look forward to how your current project turns out. Next year I going to be looking at some new mains and will be considering your Modula MT XE in the MMT version. Not sure if anyone actually built them. I have the set of waveguides I got from Joni in Finland. If not the Modulas I have an idea for something different. More to come.
Chris

[JonMarsh]

OK, today is an example of how you have to be real careful and double check your facts...

While working on the crossover update, I've been listening to the system with the Benchmark AHB2's in there... excellent sound, but at one point even I couldn't believe how much better some Andreas Vollweider cuts from "White Wind" sounded- like a VERY good remaster... well, I checked the files, and my backups, and though the 1984 original was a stunning CD for it's time, they did remaster it in 2009, and that's what I have on the music server setup...

OTOH, I have listened to it before on the music server setup (not the same streamer- running the Aries right now) and it seems like it's in a definitely upgraded league compared to when I heard it with the Cambridge Audio 840W XD power amp. Really, really clean in the midrange, more like listening to headphones that speakers, just lots of dynamic expression with integrity all up and down the spectrum.

My colleague from Munich is teasing me with the idea of leaving them here until at least January, as he's got a lot of new updates to integrate and evaluate into his system, and figures he should stay with his Halcro's or Pass for now- of course, I completely agree, if it means I have these to listen to for another month or more... he's even hinting he might sell this set to me, but I told him he'd be cheating himself to not hear them, especially as portable as they are.

Still, if 100watts per channel in normal stereo will do for you, these are a must listen to. I'm running bridge mono, which into the 6 ohm load of the Ardents give about 480W at clip. Nice...

I haven't tried out the Benchmark speaker cables yet- I've got some of the Cardas Banana to spade adapters, so I can put them in later this month and see how they compare with the Golden reference cables. They have the advantage of Speakon at the amplifier end. Uses Canare star quad cable, net AWG about 11.

[Steve Manning]

OK, today is an example of how you have to be real careful and double check your facts...

While working on the crossover update, I've been listening to the system with the Benchmark AHB2's in there... excellent sound, but at one point even I couldn't believe how much better some Andreas Vollweider cuts from "White Wind" sounded- like a VERY good remaster... well, I checked the files, and my backups, and though the 1984 original was a stunning CD for it's time, they did remaster it in 2009, and that's what I have on the music server setup...

OTOH, I have listened to it before on the music server setup (not the same streamer- running the Aries right now) and it seems like it's in a definitely upgraded league compared to when I heard it with the Cambridge Audio 840W XD power amp. Really, really clean in the midrange, more like listening to headphones that speakers, just lots of dynamic expression with integrity all up and down the spectrum.

My colleague from Munich is teasing me with the idea of leaving them here until at least January, as he's got a lot of new updates to integrate and evaluate into his system, and figures he should stay with his Halcro's or Pass for now- of course, I completely agree, if it means I have these to listen to for another month or more... he's even hinting he might sell this set to me, but I told him he'd be cheating himself to not hear them, especially as portable as they are.

Still, if 100watts per channel in normal stereo will do for you, these are a must listen to. I'm running bridge mono, which into the 6 ohm load of the Ardents give about 480W at clip. Nice...

I haven't tried out the Benchmark speaker cables yet- I've got some of the Cardas Banana to spade adapters, so I can put them in later this month and see how they compare with the Golden reference cables. They have the advantage of Speakon at the amplifier end. Uses Canare star quad cable, net AWG about 11.

Do I see a pair of your own Benchmark's in the not too distant future, say not long after the others head off to Munich

[dar47]

How many small form factor amps do you need? NAD M22, Ncore parts for a build, now these, haha. Heard the Ncore's at a friends and he going to let me have a try on my Ardent's next weekend he is away at his farm. If our dollar wasn't so bad I would consider the NAD but I wonder if it's a sonic difference at another $2000. more or just more power.

[JonMarsh]

Do I see a pair of your own Benchmark's in the not too distant future, say not long after the others head off to Munich

It's a possibility, unless I blow all my bucks on the Audio Precision, OR, I find that the M22 holds it's ground against it. OTOH, I'm personally inclined at this point to look at the AHB2 as something of a reference standard- that might not agree with a lot of folks, but it's hard to argue with what I'm hearing and what others have measured. It kicks butt at it's power range with amps costing 10x as much....

[JonMarsh]

How many small form factor amps do you need? NAD M22, Ncore parts for a build, now these, haha. Heard the Ncore's at a friends and he going to let me have a try on my Ardent's next weekend he is away at his farm. If our dollar wasn't so bad I would consider the NAD but I wonder if it's a sonic difference at another $2000. more or just more power.

You should give it a good long listen when you get the chance... just remember it may leave you wishing for your own!

[JonMarsh]

Thinking about this overnight, and decided to rework the tweeter crossover, go for flattening the response on axis in the 2-5 kHz region, which will result in a slight BBC dip off axis. May be the lesser of evils overall... also improved the damping and the attenuation in the stop band a bit.



But I haven't just been a Mac Jockey this morning, since the new 12" blade for the DeWalt arrived yesterday evening, I mounted that and cross cut the previously glued up front panels, top and bottom panels, and the single thickness back panels. Mmmm, love working with a brand new super sharp blade for laminate work! The old blade was used for the entire original Isiris build; considering that, it's in pretty good shape, and would be fine for a lot of kinds of work. I have to say that DWS780 is a great saw, it's a real pleasure to use, though loosening and moving the blade guard out of the way to put in a new blade is a bit finicky.

Now it's pricing out the crossover parts, and getting back to work-work the rest of the day.

I mean, I know slow work takes time, but this has been ridiculous...

Well, now that I've had a semi-normal weekend, I can report that I did finally build a test board for the revised crossover, but didn't have time to test it, what with other stuff going on... still, it's encouraging to feel like I'm getting back in the normal swing of things. And had a great dinner with daughter and her husband Sunday evening.

[JonMarsh]

Finally an update to post. There has been other work going on this, a collaboration with another forum member, but until we're sure that's going to work out technically the way we hope, we figure we should just work in the background.

But crossover testing, mmm, that's my job, for sure. Finally got a chance today to gear up and do some testing in the family room again.



The new scope is a lot nicer for signal monitoring than my old HP- it's a 12bit model all the time, 15-16 bits in high resolution mode, with a display to match- makes the Tek scopes at work feel a bit crude. I'm still just testing a box lash up to do an approximate acoustic prototype- have started back on the set of test boxes, but what with XMAS and chocolate eating dogs, finishing those is still a ways off.



After some testing and listening again, I once more tweaked the tweeter levels, but found that the midrange seems OK with the last design changes in September.



Overall the updated tweeter crossover is doing what I want- helps reduce the on axis hump and notably lowers and smooths the distortion profile in the mid to tweeter crossover region.






This is an on axis plot, and is actually the worst; 5-15 degrees off axis is substantially smoother, so since that's where more of the power response is, I'm going to leave things that way, based on that theory and how it actually sounds.

I also checked the PR output near field; no surprises there; I like no surprises most of the time.






These are doing what I hoped on the bottom end- play them at modest levels, and they sound well balanced but nothing draws attention to the low end. Crank them up a bit, say, to 20V P, 40V peak to peak, something that's no problem for a good 50W amp,



and you notice they're clean, tight, and deep, and sound better the louder you turn them up. Oops, the louder you turn IT up! There is no they, just one speaker! That makes it even more impressive to me. At this point the SW223BD02 is moving about 1/4" P-P, and depending on if the program material goes low enough, the PR is moving in the same range, and it's all generating some nice SPL's.

That's a dangerous thing about comparing one speaker to what you normally hear as a pair.

Listening was done with a variety of material, and leaving the speaker where it was setup and moving around a lot, from sitting on the floor to standing up. Yup, like those coincident drivers.

Test tracks included:

Hoy se cumplen seis semanas -Guasabara

All or Nothing at All -Daria

Sunshine of Your Love -Daria

What I Am -Edi Brickell & The New Bohemians

East River Blue -Spyro Gyra

No One is to Blame -Howard Jones

Chorale No. 1 "Sleeper Awaken" -Jacque Loussier Trio, live cut

They Dance Alone -Sting

Dark Alan (from Rob Roy soundtrack) -Karen Matheson

Treasure Island -Mary Black

Amhrán Pheadar Breathnach -Maighréad Ní Dhomhnaill

Against the Wind -Maire Brennan

Ny Kiree Fo Niaghtey -Poor Clares

I Wonder as I Wander -Poor Clares

A Blessing -Poor Clares



OK, I don't think I should finish this without a little bit of tease, to get in to the whole Star Wars/X-Files mood of things. Stephen Manning is a Whiz with Sketchup, and now he's got me learning, with the help of a couple of good books, so here's a glimpse of a possible implementation concept for this that's been worked up... many a slip twixt the cup and the lip, and he may kill me for tipping our hand a little, but frankly, I'm pretty dang excited... :W :B







Yes, you guessed it, crossover in the base of the stand. And yes, this is going to be a metric ton of LBL ply... (well, close to it...)


Between these construction concepts and what I'm hearing today, I'm looking forward to early 2016!

[sdl2112]

Looking good there Jon :T. I'm glad to see you back making progress....and nice scope by the way.

Between you and Steve this should be a very nice project. I'm anxious to see the progress!

[JonMarsh]

Steve has been worth his weight in gold on this, he's very good running down details and vendors, and really did nice work in SketchUp for the concept drawing. I'm not giving everything away yet, though... :W

As we know from past projects he's posted about, he's a craftsman of the first order, so I'm looking forward to see how this turns out...

BTW, when I mention smoother off axis, this is what we're talking about.

[Steve Manning]

OK, I don't think I should finish this without a little bit of tease, to get in to the whole Star Wars/X-Files mood of things. Stephen Manning is a Whiz with Sketchup, and now he's got me learning, with the help of a couple of good books, so here's a glimpse of a possible implementation concept for this that's been worked up... many a slip twixt the cup and the lip, and he may kill me for tipping our hand a little, but frankly, I'm pretty dang excited... :W :B







Yes, you guessed it, crossover in the base of the stand. And yes, this is going to be a metric ton of LBL ply... (well, close to it...)


Between these construction concepts and what I'm hearing today, I'm looking forward to early 2016!

Kids ...... can't keep a secret for anything :roll: Must be all the excitement from Christmas and the new toys. At least the dog ate some of the candy, so we don't have to worry too much about the sugar high as well.

As for the metric ton, almost, ~1200 lbs will be needed. 8O

[JonMarsh]

Dang it, Masha (the Siberian Husky) ate ALL of the candy, all 2 lb of See's mixed nuts and chews! She took that box out to her favorite spot in the back yard and killed it! She was the one with the sugar high on Christmas Eve!

We were just worried to death, because chocolate is poison to dogs, and that much chocolate would kill many dogs her size. She hardly noticed it. Must be the same genes that allow Russians to drink so much Vodka without overly untoward results. Actually, the gal who locally has run a Husky rescue operation for many many years (OK, let's be straight- decades) says they have real tough stomachs and constitutions. But still, there's a straight forward calculation of chocolate per pound of dog, and Masha would have been dead if she were some other breeds. And her son would have been in the dog house for not minding the doors properly.

Later today I hope to hook up the acoustic demonstrator to the real system (not the test system for speaker measurements) and see what it sounds like on that.