Modula Xtreme follow up

[HareBrained]

Dang- you guys are too young to be under this much stress all the time and having to deal with it that way!!

Eventually, you get old enough that you no longer care enough to stress out about it. You put in your 40 and they find someone else to answer "How high?" when they say jump.

Gentlemen, you need to move past this. Only play their games if you want to. I at least get paid for every hour I work, and I still find anything north of 50 is way too much.

Back on topic: Jon, the midrange circuit on your diagram has a dead short to the left of the LCRs. I'm guessing that was unintentional.

[JonMarsh]

Eventually, you get old enough that you no longer care enough to stress out about it. You put in your 40 and they find someone else to answer "How high?" when they say jump.

Gentlemen, you need to move past this. Only play their games if you want to. I at least get paid for every hour I work, and I still find anything north of 50 is way too much.

Back on topic: Jon, the midrange circuit on your diagram has a dead short to the left of the LCRs. I'm guessing that was unintentional.

Thanks! Very much so... when "cleaning up" I must not have deleted a wire I meant to, and it completed the connection.

That's what happens working on stuff in the wee hours... will update it soon.

Thanks.

[Bear]

As Jed wrote, there are a variety of things that may go into the final decision about the enclosure size and volume. I'm using up a bit of the rear volume for the hardware related to the waveguide. Also, this is the smallest enclosure with adequate (Bearly!) front panel space.

In this case, the baffle step is actually part of the roll off to get the Duelund curve, and I do need the base cabinet response to be moderately extended. Because of the large deep LBL brace in the center of the baffle, the rear space for the C173N is almost like a short folded TL, as the brace goes back to the cabinet center brace, and the rear wave then folds around and through the top hole back to the area above the woofer. All of this area is stuffed with long fiber wool. Seems to work pretty nice.

This shows a nearfield plot of the midrange mid way through crossover updates; it highlights the response needed BEFORE the effect of baffle step below 1 kHz. With baffle step, the response at 200 Hz is about 6 dB lower farfield, as you'd expect.

Considering everything with the range the mid must cover (about 100 Hz to 6 kHz) I wouldn't change the rear volume based on my experience with this. I'd probably rather have a different shape enclosure, and get rid of the diffraction bump on axis at 2 kHz, but this is a Modula with prebuilt cabinets (well, sort of!), so that's one limitation. No way I'd have had the time to build a pair of Isis clones in the same time frame I did these!

Jon - Thanks for the explanation!

[Johnloudb]

Now spinning... Mike Garson's Jazz Hat

Reference Recordings CD. Shame on you if you buy the MP3 version from Amazon! :twisted:

I'll have to get that. He played live at the Stereophile show in '93 or '94 in San Fransisco and I had never heard of him at the time, but it was a very good and very memorable performance.

He played some Gershwin and other stuff.

[synthguy]

I'm pretty dang happy with them- relatively compact, great midrange (I may have owned the T6-C90 longer than Jed, but he's been working and listening to them longer- this is a great midrange driver!), and lots of dynamic detail all up and down the range, due to the low driver distortion (those W26 are super once you get them tamed!) Nice clean bottom end to a bit below 40 Hz, high 30's. They will play loud for the size... think of them as miniature Wilson's.

Oh lordie... those dreaded words. Now I want a pair! ;x(

I don't suppose you or Jed have something Wilsonesque in the neighborhood of $2500 or less... or would that be the Statements or Zaph Revelators?

[Jed]

Oh lordie... those dreaded words. Now I want a pair! ;x(

I don't suppose you or Jed have something Wilsonesque in the neighborhood of $2500 or less... or would that be the Statements or Zaph Revelators?

A lot can be done with that budget.

[TacoD]

A lot can be done with that budget.

Especially if you do not have to pay commission and go the full DIY route, e.g.,

Scan6600 + Accuton C50-8-44 + 2x Eton 8-800 = 220 + 275 + 342 = 837/speaker. In that case you've 827 dollar left for 2 cross-over, and 2 cabinets.

Of course there are many other options, including replacing the Eton with Seas L22 or SB 23. Or a complete different concept altogether.

[JonMarsh]

Jed's probably your best bet- I'm not holding back any secret projects at this point- the best thing I might have coming up to meet your budget would be the Modula Xtreme SO (Sort Of), which will be the same basic configuration, same tweeter, but use RS270 on the bottom end and likely the Vifa NE180W for the midrange.

Frankly, I have some reservations about the feasibility of that design, not because it can't be built and won't work well, but because it will probably require something like a small Aragon amp at least to drive it, due to overall low load impedance.

The NE180W looks very promising in a midrange role.





But between the paralleled RS270's and the 4 ohm midrange, it will take some careful crossover work to not wind up with a 3 ohm speaker in significant parts of the range- may be unavoidable. I think I can pad the midrange Z a bit due to it's sensitivity, but right now we're just at the point of champagne wishes and caviar dreams.

So if you've got an Aragon 8008 or Cambridge Audio 840W, or something else happy with low Z loads, this might be just the ticket...

Driver cost is reasonable, four of the RS270 being $320, two of the NE180W totaling $190, and a pair of D2608/9130 plus H65 waveguides at $180. That's $690 for ALL the drivers, leaving quite a bit for enclosures and crossover bits- the latter won't be much cheaper than the Modula Xtreme standard version, as the flux caps are also required, and at least Clarity ESA caps recommended for midrange and tweeter. This may wind up being one of my best "budget" designs, but obviously oriented more towards the performance end of the spectrum.

[Jed]

Scan6600 + Accuton C50-8-44 + 2x Eton 8-800 = 220 + 275 + 342 = 837/speaker. ,.

I'd use something a bit different than the Scan6600 on the top end or one with less expense (Scan Speak HDS, Seas 22tafg, 3/4" Scan Speak Illuminator... come to mind), since with a mid dome you can capitalize on the dispersion characteristics of a narrower diameter tweeter because of the addition of the dome mid handling the lower frequencies. To illustrate this point, we know the 6600 can cross low but doesn't have the best off axis response on the top end compared to something like a smaller diameter tweeter in Scan Speak's own line. It therefore makes good sense to build on the strengths of a tweeter with better dispersion, but cross around 3.5k and rely on the mid dome to cover the region from 900hz on up to the tweeter Fc. Each driver works in its lowest distortion passband and the strengths of each driver's dispersion is maximized rather than a one size fits all approach. Not saying you are wrong, just this would be my approach if using the C50-44 mid.

The C50-44 is also one of my favorite drivers.

Jed

[JonMarsh]

Now spinning on Sunday

Powerplay...




Jack of Hearts



SACD version is on the way-

trio work with Larry Goldings on B3, Jeff Hamilton and Jim Keltner on drums! (about half the cuts for Jeff and Jim each).

[Bear]

I'd use something a bit different than the Scan6600 on the top end or one with less expense (Scan Speak HDS, Seas 22tafg, 3/4" Scan Speak Illuminator... come to mind), since with a mid dome you can capitalize on the dispersion characteristics of a narrower diameter tweeter because of the addition of the dome mid handling the lower frequencies. To illustrate this point, we know the 6600 can cross low but doesn't have the best off axis response on the top end compared to something like a smaller diameter tweeter in Scan Speak's own line. It therefore makes good sense to build on the strengths of a tweeter with better dispersion, but cross around 3.5k and rely on the mid dome to cover the region from 900hz on up to the tweeter Fc. Each driver works in its lowest distortion passband and the strengths of each driver's dispersion is maximized rather than a one size fits all approach. Not saying you are wrong, just this would be my approach if using the C50-44 mid.

The C50-44 is also one of my favorite drivers.

Jed

Jed - Have you been able to do any distortion testing on the 3/4" ScanSpeaks? Voice Coil had a test of one of the small-format ring radiators recently, but I think it was the 1" version (going off of memory). Since the 3/4" ones also use a smaller form factor (compact face plate), I'd be curious how they perform in your test rig vs. their larger kin.

[Jed]

Jed - Have you been able to do any distortion testing on the 3/4" ScanSpeaks? Voice Coil had a test of one of the small-format ring radiators recently, but I think it was the 1" version (going off of memory). Since the 3/4" ones also use a smaller form factor (compact face plate), I'd be curious how they perform in your test rig vs. their larger kin.

I'd like to try it sometime but have not. I think Jon has a pair though.

Note, in the application I mentioned above most anything will have acceptable harmonic distortion performance above 3.5k.

[synthguy]

I love the look of those Modulas! Well, the one anyway. Jon managed to make them look less boxy than elegant, as handsome as many manufactured speakers I've wanted. Wish I could afford them, but those Accutons themselves cost more than many projects. But if you want speakers that "put you there," I can certainly understand the cost-is-no-object approach.

Darn, if these aren't one of the best looking speakers on the boards! To me anyway, though I'm a much bigger fan of dark reddish veneer. Just out of curiosity Jon, are you going to present us with a BOM in that write-up?

I'm curious too as to your post above, Jed. Poking at your site, I see those SS 6600 AirCircs on many of your designs. I'm a detail freak, and get a little nervous when people bring up "affordable" drivers. And you mentioned the joys of playing with those ribbon tweeters too... maybe a PM is in order to keep from diverting the thread off track too much.

[JonMarsh]

I love the look of those Modulas! Well, the one anyway. Jon managed to make them look less boxy than elegant, as handsome as many manufactured speakers I've wanted. Wish I could afford them, but those Accutons themselves cost more than many projects. But if you want speakers that "put you there," I can certainly understand the cost-is-no-object approach.

Darn, if these aren't one of the best looking speakers on the boards! To me anyway, though I'm a much bigger fan of dark reddish veneer. Just out of curiosity Jon, are you going to present us with a BOM in that write-up?

I'm curious too as to your post above, Jed. Poking at your site, I see those SS 6600 AirCircs on many of your designs. I'm a detail freak, and get a little nervous when people bring up "affordable" drivers. And you mentioned the joys of playing with those ribbon tweeters too... maybe a PM is in order to keep from diverting the thread off track too much.

There will be a detailed if painful BOM, and a separate writeup for the SO version, as that is still in development.

This is not the official build thread, so we can "tolerate" some topic meandering... :B

In retrospect, I wish I'd had the piano black versions of the cabinets to use with the LBL baffles and detail stuff. Live and learn...

[Jed]

I'm curious too as to your post above, Jed. Poking at your site, I see those SS 6600 AirCircs on many of your designs. I'm a detail freak, and get a little nervous when people bring up "affordable" drivers.

Alright, since Jon is okay with a bit off topic talk here.......

I see speaker building as looking at the ingredients and deciding how they best will fit into the whole mix. I do indeed like the 6600 very much for applications where I need to hit LR2 slopes below 2.5k or in 2 ways with a midwoofer that needs a lower crossover point to keep the midwoofer operating more in it's pistonic range for a flatter power response. So, while the Air Circ 6600 is exceptional say from 1.5k on up, if we put the C44 in the mix at say 900hz-3.5k, that opens up a lot of opportunities to use other tweeters that may offer a bit better dispersion than the 6600, but they can't cross as low. Since we wouldn't need a tweeter that crosses low, in the end you capitalize on its strengths of dispersion and lower moving mass. This in the end would result in more detail if done right.

In theory, this is one of the reasons why a 3 way is better than a 2 way speaker.

[synthguy]

Okay Jed, I understand where you're coming from. Oh, and wordy PM sent, btw.

After getting into the whole speaker design thing a few years ago, I've been remarking to people as I began my mad search for "that" speaker, that a speaker is kind of like a musical instrument itself. Regardless of the quality of the drivers, they have to work well together. And I'm sure with Jon on crossover design. You're making a filter, much like a filter in a synthesizer, and while there are the Zaphs of the world who insist that the cheap stuff works just as well, those parts sure have something to do with the quality of sound coming from the drivers. And cheap electronics sound... well, not expensive.

Of course, then there are the Jons of the world who like to make them as complicated as a PC motherboard... :E

Just kidding, Jon, though when I first saw your XOver for the M-Exremes, I wondered if this was an active design! I also wonder if maybe a few other choices in drivers would have meant a tidier arrangement. Still, if it didn't work - and work spectacularly well, I know you'd yank those flux capacitors out by the roots.

So when are you finally going to unveil these little bookshelves to some fellow discriminating ears, or are you going to be mean and hoard them for a while?

[JonMarsh]

Okay Jed, I understand where you're coming from. Oh, and wordy PM sent, btw.

After getting into the whole speaker design thing a few years ago, I've been remarking to people as I began my mad search for "that" speaker, that a speaker is kind of like a musical instrument itself. Regardless of the quality of the drivers, they have to work well together. And I'm sure with Jon on crossover design. You're making a filter, much like a filter in a synthesizer, and while there are the Zaphs of the world who insist that the cheap stuff works just as well, those parts sure have something to do with the quality of sound coming from the drivers. And cheap electronics sound... well, not expensive.

Of course, then there are the Jons of the world who like to make them as complicated as a PC motherboard... :E

Just kidding, Jon, though when I first saw your XOver for the M-Exremes, I wondered if this was an active design! I also wonder if maybe a few other choices in drivers would have meant a tidier arrangement. Still, if it didn't work - and work spectacularly well, I know you'd yank those flux capacitors out by the roots.

So when are you finally going to unveil these little bookshelves to some fellow discriminating ears, or are you going to be mean and hoard them for a while?

Actually, I'd like to generally avoid having too many parts, because for them to do minimal damage to the signal path, they have to be pretty high grade.

This project, and the less expensive SO version, have a target transfer function for a Duelund style crossover with a 900 Hz center frequency and an aleph of 3.3



Because of the way the enclosures are built and the use of the waveguide, fortunately there are no games necessary for acoustic center compensation. To get this to work right including phase tracking, you have to manage the driver response reasonably down to at least the -20 dB level for everything to sum close to correctly, and for the relative phase to stay in track between the drivers.

Many time folks will prefer to simplify the Duelund low pass and high pass to a second order LR. That's pretty close, depending on the specific aleph alignment, and sometimes the driver gods cooperate and that works. For example, I started this design with just an LC roll off on the woofer. But alas, the driver gods don't always cooperate.

Let's look at the W26- here is the nearfield response using the 400 uF flux capacitor to kill the Qts hump and extend the low end a bit, converting the box 2nd order transfer function with a Q of about 1.3 to a nice 3rd order alignment with an F3 of about 38 and an F10 of about 30 Hz:



Alas, though I tried, with a simple LC you just can't get the attenuation in the 700-1500 Hz area right without messing up the lower midrange, so a more complex solution is needed. Yes, there may be some slightly flatter 10" woofers, or ones with different issues to deal with, but I haven't found one with lower distortion, and that was my priority.

Similarly, you'll see some LCR shunt networks on the midrange and tweeter for impedance control and driver response modification. You could leave those out, but then that would create some problems hitting the target response. Again, there are flatter midrange drivers (at least for on axis measurements), but I haven't found one with the same distortion, sensitivity, and SPL capabilities as this Accuton. It's worth working with, as Jed will tell you also. The actual filter elements are C2 and L11 as high pass elements, and L2/C3 as low pass elements. L4/C4/R2 is the LF zobel to compensate for the VERY high Q impedance peak that this very low Qts driver has, and L6/C9/R8 takes care of a bump in the response of the driver in the 4-6 kHz area, smoothing it out pretty nicely. Hard to keep things a lot simpler for a midrange crossed this low.

The tweeter requires some extra tricks because of the waveguide loading, but even there, it's a relatively minimal perfectionist crossover- Basically, the crossover is just a single cap, C6! Everything else is cleaning up the details to get that cap to work right- LF impedance control with the L5/C7/R67 zobel, and some response contour shaping with L7/C10/R9 in the middle of the waveguide range, plus an Lpad formed by R5 and R10.

I'm not sure what you meant by this:

So when are you finally going to unveil these little bookshelves to some fellow discriminating ears, or are you going to be mean and hoard them for a while?

Are you referring to these, or the SO version, or the Modula MT XE which is a book shelf? I guess you must be just joking about these being a bookshelf!

Seriously, I had planned to bring them to the Northern CA DIY, but with work that weekend, I was unable to attend.

Heck, I was just talking to ThomasW this afternoon, there's no reason if I can't get off for RMAF not to drive out and bring these to Denver then, along with a complete system, and hopefully the "completely" finished Ardents.

But as Willie the Shake said, there's many a slip twixt the cup and the lip.

[Saurav]

There's a good chance I might be able to make RMAF this year. If you and Thomas end up doing another meet at his place, please post a notice somewhere, I'd love to attend.

[JonMarsh]

Having more fun than I ought to...

Well, one of my old favorites- on this system with the Modula Xtremes, I get that chill down my neck when Harry and his band cut loose...





Gorgeous midrange on the brass and very well defined dynamics. One of my favorite recordings from 1976, but pretty hard to find in either vinyl or CD. One messed up human being, but for this album, I'll forgive a lot- others may not.


I've been playing around with an up-sampled version of the CD to 176 kHz using Wave Editor with a minimum phase apodizing filter (iZotrope licensed routines). Not ready to make a definitive statement, but it has promise, especially depending on the characteristics of the downstream DAC, and whether it can run at 176.4 native.

Saurav, that would be great if you can make it to RMAF. Obviously it's a number of months away, mid October. But I certainly won't want for accumulated vacation time, so hopefully with this years economics it will be doable for a variety of folks. Hope we see you then.

[JonMarsh]

Enjoying myself way to much...

Healing the Wounds



My daughter listened to a few of her favorite Bruce Hornsby cuts this afternoon, some KT Tunstall, and part of Raising Sand, and gave them two thumbs up, but then she's prejudiced. She knows where her Macs come from... :W

She even liked the Harry James, and wants me to burn her the album.... whooaaaa!

[silvercans]

Jon I know you find the midrange to be stellar, but what do you think about the top end (dispersion, coherency, detail, etc)? If you will, also comment on the W26 performance in this design/application.

[JonMarsh]

Well, you can't really separate out the W26- without it, the midrange doesn't work- see the transfer function target graph up above? The fuchsia curve is what the mid by itself provides, but the behavior of the woofers is critical, as they contribute significant energy up until almost 1 kHz! IF the woofers have any issue with distortion, they'll definitely muddy up the mids overall. That's a big reason I went with the W26, and two of them- killer distortion performance.

Here's some plots to illustrate the W26 distortion behavior.



This was measured for one driver with 5.6 VRMS drive, about 90 dB output level. Yes, they're clean. The only commercial speakers I've heard with this clean a fundamentals and midrange at significant output level is a Wilson Maxx 2, and the Avalon Isis (duh! - uses the same midrange).

Now, consider that my target was not the deepest low end extension possible (which would have required a much larger speaker, something on the order of the size of an Avalon Isis), but the most compact speaker using modified off the shelf Dayton cabinets in a BORG sort of fashion- I don't doubt some will figure I should be condemned to some DIY speaker hell just for thinking this up, much less doing it.

I live in a condo, so lots of below 40 Hz bass propagating through the building would not endear me to my neighbors. So the small size cabinets coupled with the "flux capacitor" technology and the T/S parameters of the SS W26 which fit perfectly to the concept was a happy marriage, in my opinion, nearly flat to 40 Hz with a 3rd order roll off below that (splits the difference between ported at 4th order and conventional sealed at 2nd order. These are very taut and convincing to me in the bottom end, I really like, for example, how bass drum is reproduced in the Sheffield Harry James; there are some songs where the band really uses dynamics to good effect, with the percussive finishes with nice impact and weight, and in this alignment, the bottom end seems to start and stop on a dime, if you know what I mean, while having very good articulation moving upwards in the bottom end, and great pitch definition. And I haven't even put the new side braces back into the cabinets, waiting for the cap upgrades to do that.

I don't know on an measurement basis if my LBL front panels have made the difference I hope for in the mid and woofer launch baffle, but you don't feel any vibration on those panels when things are playing away, so the coupling to the rest of the cabinet must be pretty good. As a stiff well controlled launch platform for the midrange, I like what I'm hearing.

Fortunately the bass cube wall resonances are relatively high in frequency, and not excited much by the operating range of the W26 in this application. Only the two side walls on each box aren't reinforced right now, and that will be fixed after the new caps are installed. Even the back panels have LBL sheets glued on for stiffening.

Now, the top end may be the weakest part of the speaker- and it's still pretty good- the main limitation being that if you stand near the speakers, there's an off axis dip in the response blend between the mid and tweeter- maybe these would work even better if the module was angled up slightly. Seated, that complete goes away.

My perception of the top end quality is rather recording dependent- it certainly reveals "issues" with poor CDs, and rewards good recordings. OTOH, it's not a match for an Accuton larger diamond tweeter, and one might prefer the Beo SS. What it does do is provide good dynamics, a pretty wide bandwidth, and surprisingly wide controlled dispersion in a conventional box. (mounting a high grade conventional tweeter in a conventional box like this will produce rather suboptimal results for several reasons).

This plot may not look that impressive at first- on axis, 30 degrees, 45 degrees and 60 degrees! But go measure some other speakers at 60 degrees and see if they can maintain a smooth energy curve out to 60 degrees with significant energy at nearly 15 kHz.



These measurements were made with the system close to a back wall, (which lifted the 70-175 Hz area, and with a bass null at the measurement position at 42 Hz- wasn't trying to get nice bottom end data for this test), and as you can see 0 degrees and 30 degrees are nearly identical. Something that many conventional tweeters won't remotely do out to 20 kHz. So, the power response is smooth even far off axis and well controlled, with a gradual roll off of top end energy. Works for me.

So, considering that this was supposed to be a system that could be put together really quickly without any heavy duty wood working (of course, that's a judgement call as to what constitutes heavy duty wood working- there were two table saws and lots of bevel cuts involved!), I think it turned out above my expectations. No obvious things I can think of that I would change, within the constraints of a "Modula" system (built using PE cabinets) other than the upcoming cap upgrades.

The real challenge will be to see how much of the "magic" can be retained going to RS270's, the Vifa NE180W, and the same tweeter waveguide on the top end. I may look around to see if there's any other possible woofer candidate, but 10" woofers with low distortion up to 1 kHz seem to be about as common as hen's teeth.

[JonMarsh]

One other plot I forgot, tweeter distortion with network

Measured response with crossover network at 90 dB output for just the H65+D2608/9130 combo.



For reasons I cannot explain, the HD2 and HD3 are much closer in level than for the tweeter by itself. Acoustic loading? Throat effects? Dunno....

If you think that I believe this is a pretty nice combo of an $80 tweeter and a modified $10 waveguide, you'd be right...

[brucemck2]

Jon, now that you've had them running for awhile, do you prefer these or your Ardents?

[TacoD]

I'd use something a bit different than the Scan6600 on the top end or one with less expense (Scan Speak HDS, Seas 22tafg, 3/4" Scan Speak Illuminator... come to mind), since with a mid dome you can capitalize on the dispersion characteristics of a narrower diameter tweeter because of the addition of the dome mid handling the lower frequencies. To illustrate this point, we know the 6600 can cross low but doesn't have the best off axis response on the top end compared to something like a smaller diameter tweeter in Scan Speak's own line. It therefore makes good sense to build on the strengths of a tweeter with better dispersion, but cross around 3.5k and rely on the mid dome to cover the region from 900hz on up to the tweeter Fc. Each driver works in its lowest distortion passband and the strengths of each driver's dispersion is maximized rather than a one size fits all approach. Not saying you are wrong, just this would be my approach if using the C50-44 mid.

The C50-44 is also one of my favorite drivers.

Jed

The 3/4" scanspeaks are somewhat limited in efficiency, therefore I went for the "safe bet". I used the 22 taf it isn't a bad tweeter, but better tweeters exist. Using a full fledged 1" dome, of which the 6600 has the better dispersion compared to other large size domes, you can do full Duelund 3-way without suffering a rise in distorion a typical 19 mm might give you in that situation.

Other than that: there are many ways to arrive at a top speaker design for the money available.

[JonMarsh]

For now, these clearly- OTOH, I am going back to revisit some crossover stuff with the Ardents shortly. You know, apply what we learned in the Super Ultra Flagship system to an update on our Ne cest Plus system.

The Ardent is limited in LF output in comparison- you've gotta realize, dual 10" SS woofers with 9 mm Xmax can move a bit of air, and as the system has a well controlled roll off, they don't get overdrive easy. The T6-C90 mids will play LOUD! While staying clean. Well, say, -55 dB HD3 at 105 db output from 300 Hz to 3 kHz.

But I've decided to experiment with some different tradeoffs in the crossover, not try to keep the LF impedance as high as I did, which necessitates some compromises and requires the LF zobel network. May not pan out, but if it does, I think I can improve the area below 500 Hz.

I really do like the sound of the Be 6640 tweeter, and the overall presentation of the Ardents from 700 Hz to 20 kHz is fairly pleasing to me... I'm just wondering if there isn't a little more performance left lurking in there, particularly with the right power amps.

If I had them to do all over again, the size would be the same, but I'd hazard trying dual SS W22 8" woofers (the little brothers to the W26) in a sealed flux capacitor alignment, for the same reasons. I'm afraid I don't have the spare time to try building that any time this year... but maybe a PE box rapid proto- I've got the SS W22's and an extra C79. And most of the PE boxes needed.

Trouble is I have more interesting ideas than I have time.

Sure wish I was wealthy and retired... man could I have some fun!!

[Jed]

For now, these clearly- OTOH, I am going back to revisit some crossover stuff with the Ardents shortly. You know, apply what we learned in the Super Ultra Flagship system to an update on our Ne cest Plus system.

Yes, and you know what that means when you're "done" with the Ardent revision.... it's back to the Super Ultra Flagship system. It never ends, this quest.

Might as well go "all out" and try the 4 way Duelund and stop wasting time, Jon. I do admire your design studies in the meantime. :T

Jed

[TacoD]

Jon: I'm a happy user of the 26W myself for some years now, but my alignment is highly overdamped (one driver in ~70 liters closed box). The only thing lacking at the moment is that I got the impression that on low to very low SPL levels I get a noticable reduction in bass resolution. Whilst the Audiotechnology driver and tweeter on the mid-high do not show this reduction in resolution. The large ATs of course have trade-offs in cone rigidity, however, when I used those in other designs they did not suffer from this apparent loss.

What is your experience in a less overdamped config?

[Jed]

The 26W is fairly low sensitivity and needs some juice to get them playing their best. Perhaps that is why you prefer the higher sensitivity Audio Tech driver for low SPL levels? I prefer the 26W ported, myself. Although I haven't tried the flux capacitor route to extend the bass response in a smaller sealed box.

Jed

[TacoD]

The 26W is fairly low sensitivity and needs some juice to get them playing their best. Perhaps that is why you prefer the higher sensitivity Audio Tech driver for low SPL levels? I prefer the 26W ported, myself. Although I haven't tried the flux capacitor route to extend the bass response in a smaller sealed box.

Jed

It isn't just a "juice" issue, I think it is an increase in distortion at (very) small cone excursions due to losses in the suspension and/or spider. Strangely the Vas of the 26W is rather high, and thus pointing at a low loss surround.

I will experiment a bit more, we really do not want the remainder of the world judge us as too fussy about these expensive drivers .

The only commercial speaker, next to the Isis, which impressed me with real low distortions in the whole pass-band, but especially in the bass, was the Vivid Giya. Amazing!

[JonMarsh]

Ah, you mean the ones by the ex B&W Nautilus guy? Never heard those, but I bet they're impressive. Heard that he thinks that the Giya G1 is the completion of his work with B&W, which was never finished there.

Taco, without hearing first hand what you mean, it's hard to say that I really understand your subjective response about the low level performance.

Compared with older SS drivers, it seems to me the suspension is quite compliant and rather linear- I remember for the old 8" kevlar woofers you got rather different T/S parameters depending on whether you drove them with a hundred milliwatts or so or 3-4 watts. I don't see the same evidence of this, with the new W series drivers (W22 and W26), and the distortion behavior, which would be affected by this, is just amazingly impeccable for something you can buy off the street, so to speak.

The most complementary thing I can say about the W26 once you get it worked out right, is that it just kind of disappears... what ever is going on with the music "goes on...".

The funny thing about this project is that the bottom end is reminiscent of newer Avalon systems I've heard that worked well- that is, they don't generally have very deep bass, but the stuff down to the mid 30's range is very taut, and if you place them for some room lift in the right frequency range (so that the boundary lift occurs lower in frequency), then you can still get fairly good subjective extension.

I can imagine that a larger conventional sealed enclosure could have some sonic advantages, perhaps also the ported, (though while I've been happy with the general detail and definition of the overdamped ported systems I've done, they don't sound as good/neutral as these).

The kicker with these is double 10's in a small package- lots of driver output at fairly low distortion- and they're only 44" tall and at the deepest point, just 14" deep!

The midbass to midrange balance and resolution does all kinds of things, including some of the best sounding piano and Hammond B3 reproduction I've heard. My daughter has been developing a taste for Led Zepplin lately (of all things- some friends introducing her to their later albums, so Sunday I put on "Your Time is Gonna Come"- cranked it a bit, with the pipe organ intro- she had no idea what was coming. She's used to me putting on these spacy new age and classical things... the B3 stuff later in the cut is pretty nice, too, clearer than I've heard before.

Oh well, break's over, time to get back to pushing pixels, and some more music...

[TacoD]

Yes, I meant the speakers from (ex- B&W) Laurence Dickie.

Also I think the best 12" I used is the Eton 12" Hex, the motor system was not advanced at all but the cone is a dream. Due to the thick cone no energy is coming back through the cone itself. So I am tempted to try a sandwich Audiotechnology woofer. Same idea different (more beefy) motor.

[JonMarsh]

Yes, and you know what that means when you're "done" with the Ardent revision.... it's back to the Super Ultra Flagship system. It never ends, this quest.

Might as well go "all out" and try the 4 way Duelund and stop wasting time, Jon. I do admire your design studies in the meantime. :T

Jed

Oh, Jed, I just think you get some chuckles watching me stumble around in the dark a bit, is all! :W

The trouble with these "design studies" is that I haven't had the time to make them at all rigorous in that regards- that is, I try three or four new things all at once, and once it's sorted out, perhaps I really like the results, but how much does each contribute? What have I really established even just to myself about desired methodology and materials?

Is it the low NL distortion drivers? (Zaph would probably argue not... as he admits, in spite of what he is known for) Is it the vibration controlled boutique caps? (Zaph would CERTAINLY argue it's not!) Control of linear distortion and energy storage in the drivers and cabinet? Is it the very stiff front baffles and generally rigid cabinets using LBL in critical construction? (hey, I've been on that band wagon a long time, since the late 70's, but here we're trying some different things- one thing that I think is a common thread for some of the real functionally successful high end speakers is very rigid cabinet construction, whether you're looking at Magico, YG Acoustics, Rockport, Avalon, etc.

Ideally I'd like to have an outcome from a design study in which I feel I really have a handle on what is necessary to hit the target goals, without overshooting in effort or materials in any one area (yeah, that's probably thinking too much like a manufacturer, and that isn't me).

But that I haven't succeeded in at all!

But as far as neutrality and resolution and just plain ole gosh darn naturalness, I'm quite pleased with the current outcome- might be the first set of speakers I've done I'd be willing to put up against Orions. And as my aural memory of Orions is one of the first things I'm always comparing any commercially auditioned speaker to, that's not a small statement.

Obviously, more money in drivers here, but a lot less in crossovers and amplifiers!

Maybe it's just time to put on some music and eat some lunch!




Oh well...

And Face is getting his drivers together for a new system...

W26... check!
C173N-6-90... check!
tweeter, I think he's still agonizing on that choice.... :W

[JonMarsh]

Guilty pleasures with deep bass



Goldie Oldie....

[spadez]

Excuse me for being incredibly ignorant, but this is the impression I had:

Newer music is higher in sound quality than older music. If your going to test a speaker system for sound quality, surely you want to be feeding the highest quality music you have into it to see what you can pick up, rather than music that was recorded over 30 years ago?

This isnt a dig at anyone music tastes, it just seems like audiophiles test with older music, and may be missing out in modern advances in recorded sound quality.

[benchtester]

Excuse me for being incredibly ignorant, but this is the impression I had:

Newer music is higher in sound quality than older music. If your going to test a speaker system for sound quality, surely you want to be feeding the highest quality music you have into it to see what you can pick up, rather than music that was recorded over 30 years ago?

This isnt a dig at anyone music tastes, it just seems like audiophiles test with older music, and may be missing out in modern advances in recorded sound quality.

In theory, yes, the technology is there. However, in practice modern recordings are often compressed and/or amplified into garbage. Here is a current thread:

http://techtalk.parts-express.com/showthread.php?t=217762

Some of my best test tracks are old analog recordings, pretty pathetic, isn't it?

[ThomasW]

Newer music is higher in sound quality than older music.

Google the terms 'loudness wars' to see what's screwing up the sound quality of current recordings...

[Paul W]

In theory, yes, the technology is there. However, in practice modern recordings are often compressed and/or amplified into garbage. pretty pathetic, isn't it?

Yup, it's the reason my music purchases are way down from past years. I simply won't take the chance of getting a poorly engineered disk. Too bad since the technology of today could easily produce stellar recordings.

The "loudness wars" have even made me leery of potentially great sources like HD tracks...what's the point of hi-res if they use the same crappy over-compressed masters?

[numberoneoppa]

Guilty pleasures with deep bass



Goldie Oldie....

Strawberry Wine! A childhood favourite of mine.

Yes, I'm young.

[chasw98]

Heck, I was just talking to ThomasW this afternoon, there's no reason if I can't get off for RMAF not to drive out and bring these to Denver then, along with a complete system, and hopefully the "completely" finished Ardents.

But as Willie the Shake said, there's many a slip twixt the cup and the lip.

I can always fly into Livermore a little bit early and make sure you get out of the house, into an elemnt, and on the way to Denver if need be! :B

Chuck

[ColoradoTom]

Jon............

Not to hijack the thread, but what if someone wanted to take the basic design and build the cabinets from scratch combining the bass units into one box and slightly modifying the top unit like the Von Schweikert VR-4JR (image added). I assume that if the mid/hi unit had similar dimensions, crossover modifications would be none/minimal. This is starting to sound like a better option than the Ardents and the woodworker in me could still be addressed.

ColoradoTom

[JonMarsh]

Hello from Vancouver

Jon............

Not to hijack the thread, but what if someone wanted to take the basic design and build the cabinets from scratch combining the bass units into one box and slightly modifying the top unit like the Von Schweikert VR-4JR (image added). I assume that if the mid/hi unit had similar dimensions, crossover modifications would be none/minimal. This is starting to sound like a better option than the Ardents and the woodworker in me could still be addressed.

ColoradoTom

No reason I can think of that that wouldn't work OK. I was even thinking the other day that it might have been cool to tilt up the mid tweeter acxis, because these are a little short compared to some designs. The net volume for the woofers should be kept around 1 cu ft unless you want to test and possibly retune the "flux capacitors". I have parts on order for another tweak of the tweeter crossover, will build a whole new board so I can test and compare with the current version. Just optimizing the target fit a little better above 1800 Hz, and taking a simultaneous stab at reducing the electrical drive below 1500 Hz. Looks OK in LspCAD, but it's the real world that counts!

[ColoradoTom]

No reason I can think of that that wouldn't work OK. I was even thinking the other day that it might have been cool to tilt up the mid tweeter acxis, because these are a little short compared to some designs. The net volume for the woofers should be kept around 1 cu ft unless you want to test and possibly retune the "flux capacitors". I have parts on order for another tweak of the tweeter crossover, will build a whole new board so I can test and compare with the current version. Just optimizing the target fit a little better above 1800 Hz, and taking a simultaneous stab at reducing the electrical drive below 1500 Hz. Looks OK in LspCAD, but it's the real world that counts!

Cool...... just thinking about summer projects. I'm being forced to take some time off - have a disk problem (L5/S1 disk is failing and nearly bone-on-bone) hopefully with the physical therapy I'm getting I'll be back on top of things soon. Probably did it carying those darn M8ta's around 8O . I'm thinking these two unit speakers might be easier on the back!!

[Face]

Or you can snazz it up with some facets like the Pass SR1.

Images not available

[ColoradoTom]

Or you can snazz it up with some facets like the Pass SR1.

Images not available

Speaker porn.... I feel dirty! :B