Three Way Evil Design Study

[JonMarsh]

Yes it is, indeed! And my own experience is that you'll at least need some pricey caps like Clairty MR or Jantzen Superior Z in the tweeter circuit to realize the potential of a Be or diamond tweeter (of course, you'll wind up paying some attention to your front end components, too! :W )

[benthe8track]

Haha at this point if they are finished for under 5k I'm happy

[JonMarsh]

I think that will work out. BTW, I added up the total for the Isiris (at GF's request), my net total investment (NOT counting the extra crossover build), and it came to $10K. Big items were raw LBL ($1400 plus $500 shipping), Accuton Mids (currently nearly $1K each, but I paid half), the Jantzen JDT-1024 diamond tweeters ($2K each), and the crossovers- I bought the NS12's for a relative song a few years back, and have a new pair picked up in 2013 as backup spares. IMO, it's an under appreciated driver, bridging the classes between woofer and subwoofer, and having a remarkably clean, lightweight motor and a great stiff, well damped cone. It's a classic, in my opinion. I still leave 4 of the NS10-513-4A; if I was to do a "Time" clone it would be with those.

I have preliminary BOM prepared for the Wavecor Ardent crossovers, with options- mainly, if you want to go crazy on the tweeter caps, Clarity MR's for twice the price of the Jantzen Superior Z. Not sure that's a sensible upgrade... have Solen AWG 14 inductors in several locations where there is no performance impact to reduce cost.

[dar47]

So did you mention to her, or try to show her a comparable on the net that the $10K is roughly a 7 to 1 build ratio of the commercial offering? :B

For me at this point my wife doesn't say much anymore as she is out pacing me 3 to 1 on tri-athalon gear and training aids, one example is the (star ship Enterprise of a tread mill), I was happy it was way to big to go down stair at over 400lbs and end up in the sun room away from my gear.

she is going to the worlds this summer in Edmonton and she is going prepared!

[JonMarsh]

Oh, yes, she's seen Isis pictures and can follow the basics of the explanation of what's similar and different, and is aware of the price difference. She's still a bit boggled at the notion of $10 speakers, but then, I point remind her of how much she's invested in her 356 over the years, though the initial purchase price might seem reasonable.

Her husband wan't much of a tool using animal, and she realizes now to be a bit careful in the future of what she wishes for... :W

400 lb treadmill, huh? I have an Endurance 5000 elliptical that's no where near in that category, but still something I'll have to take apart to get over to GF's some time this year. She has a couple of museum piece machines and a weight bench, and we're trying to figure out what to keep and what to let go- she acknowledges my elliptical is probably a better solution than her museum grade Nordic track (which I swear looks almost as old as her 356, and similarly technology dated.- it has the sliding slats and ropes- we're talking gen 1 ski imitation). Sounds like your wife is pretty serious- hats off to her! GF used to run a lot before her hips started acting up (they're both replaced now- the second one just this last October), and has a fistful of medals to show for it, in local competitions.

[Juhazi]

[QUOTE=JonMarsh;585785]Going by the Stereophile measurements, I wonder a bit how they sound in room- (I've heard some smaller Magico's, which were quite nice) - that large front baffle shows up in a disparity between on axis measurements and off axis power response. [QUOTE]

Canucks have measured the Magico S5 ((Poor Man's Q5?) and it is stunning!

http://www.soundstagenetwork.com/index.php?option=com_content&view=article&id=1043:nrc-measurements-magico-s5-loudspeakers&catid=77:loudspeaker-measurements&Itemid=153

[JonMarsh]

Yeah, the S5's are making a stir for sure, as they represent something more "affordable" ($28,650 pair) but still very high performance, and with a much more home friendly foot print.




Nothing not to like here!





One of the things really contributing to their success is their very good wideband midrange driver. Interestingly, the S5 uses the same Scanspeak beryllium dome tweeter that we're using in the Ardent project, including the new Wavecor Ardent.

[TEK]

Monkey Coffin dry fit check passed

OK, it's been sweaty palm time, finishing up detail work on the braces, biscuiting the front panel, top piece, bottom brace, and sides, and then doing my first dry fit check for a bottom module.



For now, just laying down the braces to check the side to side spacing (by the way, it pays to round over the LBL, because a straight 90 degree corner in bamboo is SHARP! Skin cutting sharp!)



Nothing but a skosh of the finest blue tape holding these together for a dry check



Houston, we have a go for launch pad assembly... :T break out the T88 structural adhesive! :B But let's hold off on the champagne for now- maybe just some French Blood Orange soda to celebrate (yeah, not in the same category as a fine tequila, but we've got assembly operations ongoing... )

Jon, what is the wall thickness of these beauties? You did go with only bamboo, and no BB ply or MDF?

[Jonasz]

Heard the Magico S5 at a hifishow last weekend and they didn't sound anything like the nice responsecurve implies above. There were literally no bass at all wich made the speaker sound very thin and tinny. Probably a problem with the room or the woofers were disconnected 8O or something similar...

Jon I'm sure your Ardent project would easily be the better speaker.

[JonMarsh]

Maybe they did something stupid and obvious like wiring the two speakers out of phase? That would produce the kind of result you describe!

When I took the Isiris to the Northern CA DIY, one of the tweeters was wired out of phase- didn't figure that out until quite a bit later- had caused me to reverse the connections on the midrange driver. You can imagine the imaging was NOT what I had really expected for a while... ;-)

Moral: Never do things in a hurry unless you have someone else checking your work!

OTOH, I hope Stereophile reviews the S5 some day.

[JonMarsh]

Jon, what is the wall thickness of these buties? You did go with only bamboo, and no bb ply or MDF?

The Bamboo was 3/4" material.

I laminated it up with 1/4" HDF on one side for the side walls, toward the inside, of course.

I used two layers (one on each side) of 1/4" HDF for the center braces and for the tops and bottoms of the woofer cabinets.

The side braces were just straight 3/4" bamboo ply, a different style that I source locally, made with strips on edge.

The front panels were 3" thick, made of three layer of the LBL plywood.

[JonP]

Maybe they did something stupid and obvious like wiring the two speakers out of phase? That would produce the kind of result you describe!

When I took the Isiris to the Northern CA DIY, one of the tweeters was wired out of phase- didn't figure that out until quite a bit later- had caused me to reverse the connections on the midrange driver. You can imagine the imaging was NOT what I had really expected for a while... ;-)

Moral: Never do things in a hurry unless you have someone else checking your work!

OTOH, I hope Stereophile reviews the S5 some day.

Sounds like you might have called it, Jon... I got to check out a few Magico models at an event last year, including the Q7, 8O and the S5 in a smaller room really shined as a well balanced speaker. No missing bass problems noticed. I and others seemed to like them best, of the ones you'd put in a normal room. The Q7's uh, I wouldn't put in that category. A factory rep was there, so they probably were hooked up right...

The Isiris' sounded pretty good at NorCA, but I thought you seemed a bit perplexed about something. Don't know if you're ever going to move them again, but it would be nice to hear the corrected and updated crossover, if you're so inclined.

[JonMarsh]

The Isiris' sounded pretty good at NorCA, but I thought you seemed a bit perplexed about something. Don't know if you're ever going to move them again, but it would be nice to hear the corrected and updated crossover, if you're so inclined.

What you describe regarding the S5 is what I would expect...

That's an interesting question, about bringing the Isiris again- in their current form with updated crossovers, they sound quite a bit better, and I think I still have a few more tricks to implement (the internal cabinet damping in midrange enclosure, for starters) but they will be a bear to move again, as I'm planning on permanently fixing the head unit to the bass; moving them at that size and weight would be a real bear... It's necessary in order to integrate the crossovers, too. Plus I'm pondering a small external LF eq box between preamp and amp. But never say never...

OTOH, what hopefully will be ready by this May for Northern CA DIY is the Wavecor Ardent. That's become the priority project, even GF wants to see them finished.

And I did make progress this weekend, (not as much as hoped!) and will be doing initial testing with drivers next Saturday.



These are going to be a really nice system, I think- a little power hungry, but should be very well balanced top to bottom- the Wavecor's should give performance in the bottom end to match the C79 midrange and 6640 Beryllium dome tweeters. I may even cobble up a passive LT shelving EQ between the preamp and power amp...

What would be really cool is if I could finish my nCore 400 build by then, too, and sort out the DCD8 setup, but that may be hoping for too much... unless I get relief at work soon, that's not likely to happen.

New guy starts in March, but likely won't be ready to work at customer's for a while. Still, one can dream....


What I'm really dreaming of making a reality is having finished Wavecor Ardent's at the DIY meet in may, finished meaning veneered and lacquered with grille panels. That should be doable with sufficient effort. It's mine to lose at this stage, I think... (though more weekend work could put the kibosh on that- one of our guys was working Saturday and Monday over the holiday weekend, but he volunteered because he wants the comp time for more vacation visiting his home country later...)

[JonMarsh]

Going totally OCD...

Refine, refine, refine. Or go OCD. Where's the difference?

Anyway, more thinking and tweaking in LspCAD, and ordered parts to implement testing modifications to all three crossover sections, though woofer is only a resistor change...


This may just amount to playing around in the error between simulation and measurement, as the measurements look pretty good, but... just in case.



Modifications as basically noted in upper text block,

• R5: from 11 to 16 ohms
• C6: 125 uF to 85 uF
• C4: 6.8uF to 5.6uF
• C7: 15uF to 10 uF
• Some small adjustments to tweeter and midrange level via pad resistors

[JonMarsh]

BTW, this time Parts Express DID come through with Jantzen Superior Z caps in stock and Jantzen AWG16 foil inductor in stock. I just got notice of shipping this AM.

So, time permitting this weekend, (if the parts get here...) I'll whip up a test crossover, and also modify one of the midrange boards.

Things are kind of BSC with work, so I may not even get the weekend off. We'll see... usually I'm the last person called in on weekends because of the distance of the commute, and because one of the other guys wants comp time to build up vacation time.

[JonMarsh]

Updated "production" schematic, parts on hand to modify, but the Wavecor Ardent will take priority this weekend, and many to come.



Sill, I'm looking forward to getting to this- maybe over the Easter break while lacquer is drying? :W

[JonMarsh]

Does this make sense?

Just saw these are available through Madisound now... actually less expensive than the Janzen JDT-1024 I used for this build. But... hmmmm, rather curious.




Interesting appearance, in a somewhat baroque fashion... too busy for my taste.

But the really puzzling thing is the SPL response, both flatness (or lack thereof), and relatively low sensitivity at higher frequencies, such as 20 kHz (down 7-8 dB from 2-3 kHz level!):




I'm not feeling the love for these... and I can understand why Madisound is only listing these, not stocking; you want, you order, you wait.

in the meantime, while you'r waiting, we arrange a psychiatric intervention on behalf of your family... :rofl:

[Face]

It's due to the slight waveguide loading.

[5th element]

Slight waveguide loading and lack of a phase shield. If you EQ'd this flat you're talking like a real 84dB tweeter. I don't like the look of that protector either, but they have to do something to stop people poking it and everyone pretty much hates the way their normal hexagrid covers look. Having said that, the fine mesh of the DXT is pretty nice on the eyes.

Solen have had them in stock for a while now and are slightly cheaper than Mad too.

I think the new SEAS Be dome uses pretty much the same magnet/chamber/motor assembly as the diamond. Those two appear to use a completely different type of construction vs SEAS other tweeters although that might be purely cosmetic. It'd be nice to see just how the SEAS compares to the Scans in measurements, but as the price is ridiculous I can see that being a bit of a problem.

[JonMarsh]

Yeah, but an 84 dB tweeter? Usable in some configurations, including this one, but just barely?

[5th element]

I suppose it all depends on how much top octave droop you can live with as it isn't bad out to around 16k. I could live with that. It's just a shame they couldn't have made it even more sensitive. The new scan Be dome in the revelator series is similar in response shape, but as it's 8 ohms and that they've managed to squeeze more sensitivity out of it, means it's not half as much of an issue. Truth be told I'm surprised that SEAS didn't do a better job.

[JonMarsh]

Well, my colleague in crime from Munich will be here on business in the middle of June, and he's been really wanting to hear what he calls the "California Isis", so it behooves me to see if I can pull the latest simulated updates together quickly and get some measurements done, at least enough to finalize the crossover with external construction for now.




So more parts on order this lunchtime, to cover what I don't already have (fortunately do have the Clarity MR in 10uf). I really should have thought of this order yesterday, because then it might have been here before the weekend! or at least earlier today... just a bit too much going on around here right now. Well, at least there's no time to be bored!

[JonMarsh]

Well, my colleague in crime from Munich will be here on business in the middle of June, and he's been really wanting to hear what he calls the "California Isis", so it behooves me to see if I can pull the latest simulated updates together quickly and get some measurements done, at least enough to finalize the crossover with external construction for now.




So more parts on order this lunchtime, to cover what I don't already have (fortunately do have the Clarity MR in 10uf). I really should have thought of this order yesterday, because then it might have been here before the weekend! or at least earlier today... just a bit too much going on around here right now. Well, at least there's no time to be bored!

The tweaks and simulation evaluations don't stop- note C2 will likely change to 72 uF and C6 back to around 125 uF. All the parts to evaluate should be on hand by this Friday, and I'll build two new tweeter crossover boards and modify one of the new midrange boards to look mostly like the above, with the noted changes to C2 and C6. If my carefully updated SIMs are correct, this should improve flatness in the upper bass through midrange, and lock down the phase tracking between woofer and mid even more- my criteria being flatness in phase and vertical window, and quality of reverse null.

Some day I'm going to get this right... :W maybe even this year!

[JonMarsh]

Going out just a little on a limb, my money says this will fairly likely be the final configuration this weekend:




The bigger problem won't be modifying and testing the crossover, but getting GF to let me set them up optimally... at least until my friend meets us on June 11!

[JonMarsh]

Have tested the above schematic now- built up a pair of new tweeter crossovers, and updated the value of C2 also, to 72 uF total. It's nice when things measure in room pretty much like the simulation - so there are improved reverse null dips, including depth and more symmetrical, and the overall response is quthe rite smooth if you measure close enough to ignore a lot of the room reflections. Of course, that's not how we listen, so measuring at the listening position on the couch is also an interesting exercise, if not one that often looks all that pretty!

I also worked on room positioning, getting permission to for now pull them out further into the room and change the spacing and relocate the couch. These all have salutary effects, even when you're listening or measuring 6-8 feet behind the couch!

This is the "couch potato" measurement, at 15" degrees off axis from the tweeter, as they are not completely cross-fired.

The goofy thing is, sitting at the work desk behind the couch, listening to on channel of the new Oregon album, or some Jacque Loussier (88.2 kHz material downconverter from ripped SACD) they sound like they have center fill to the middle of the room, even though there's only the left channel playing through the test setup. Hmmm, probably had a glass too many of chardonnay with dinner....:W

[JonMarsh]

I'll take some pics of the modified setup sometime in the next few days. GF is being fairly patient to let me set things up "right". The problem for me is going to be going back to the old way- pulling the speakers into the room and moving back the couch sounds like it has tightened up everything top to bottom, while at the same time increasing authority on transients, especially LF ones, as we've greatly ameliorated the dip in the 50 Hz area, among other things. Here's the old in room response with the cabinets in the "normal" position- compare with the above in the last post.


OLD SETUP measurement for Reference



With the new positioning, and the full MR Clarity tweeter crossover update, (updated design and updated caps from Jantzen Z Superior) tweaked midrange phase control to both the LF and HF transitions, and I suppose, the inherent cabinet stiffness, this speaker just sounds amazingly fast to me- that was my reaction listening to a variety of familiar program material Saturday evening. It's going to be hard going back to the old room positioning. Maybe if I can get GF hooked on the sound setup this way, I won't have to.

Sunday I got the Rubidium oscillator and power supply wired and setup, and the DCD8 back into the system (first time since over at GF's), but with 100+ temperatures I was pretty tired, and had dinner planned with daughter- so no real time for listening that evening. There are still a few settings to tweak in the DCD8, too. But putting on one of Enya's later albums, which shed bought several of in mint shape at some garage sale, GF was impressed and pleased with the sound. As she put it, it sounded like a whole different piece of music from playing it on her Sony Dream Machine!

[5th element]

Comparatively it probably was a whole different piece of music

[JonMarsh]

Comparatively it probably was a whole different piece of music

that's a very good way of putting it... just like this CD called "Flute Dreams" by Alice Gomez, which sounds pretty OK on the Sony Dream machine in her bedroom, but sounds more like an audiophile demo disk in the family room- it's surprisingly well recorded.

[JonMarsh]

Alien Abduction? Who knows... what has been heard cannot be unheard...

This afternoon we had a lengthy listening session, with several specific pieces of music which I'm quite familiar with, several of which my colleague is also similarly familiar.

From the "Music of Cuba" (hand carried import) the first track "Hoy Se Cumplen Seis Semanas"
From "Flute Dreams", the cut "Mystic Temple"
From the Curandero CD "Aras", the title cut "Aras"
From the Poor Clares CD "Songs for Midwinter" "Ny Kirree of Niaghtey (the sheep are under the snow)
From Plays Bach: The 50th Anniversary Edition" the last cut "Sleepers Awake" - (live recording)
From Jazz at the Pawnshop, 30th Anniversary edition, the 4th cut "High Life"
From Shelby Lynn, "Just a little Lovin'" the title cut "Just a little Lovin'"

The cuts we both have a lot of experience with are "Aras", "Sleepers Awake", and "High Life". We were doing some comparative listening also, after making some changes in the system configuration. This is where things veer off into the realm of what as an engineer I would call a dose of unreality, except that I heard what I heard, and what has been heard cannot be unheard. Maybe I can just write off that part as being alien abduction or something similar, but it's something that makes me fairly uncomfortable as an engineer. At the end of that phase we also finally sorted out the DCD-8 settings and got the 10MHz clock integrated into the re-clocking flow.

First , let me say very quickly that my friend was quite favorably impressed with the Isiris, which he likes to call "California Isis". (as opposed to Colorado Isis, I suppose? ) Like my own listening impressions, he finds the midrange and treble to be very fast and clean, and in that regard he was also favorably impressed with my "little" Cambridge Audio 840W, given that he's used to the likes of the Boulder 2060 and CAT JL-1 Signature tube mono blocks. He thought the system reminded him of the Kharma Exquisite Mini, (which have a different Accuton 7" midwoofer and custom Accuton diamond tweeter), except that the Isiris has more midrange and bass authority and might even be a bit sweeter and cleaner in the top end (but then he never heard those speakers with anything beyond his Antelope Zodiac Golds, without the DCD8 re-clocking.) (BTW, though the Exquisite Mini is a smallish two way system, which retailed for ~45K USD per pair.) He was somewhat amazed at how integrated sounding they were even sitting close up, or standing. Credit the NatalieP style crossover for that, I think, and I did my best to explain how that works- he has some engineering background, but he's in top management for sales and marketing reporting to the CEO, so expectations should be reasonable.

OK, the weirdness came in about half way through our listening session, after we'd been through most of the cuts for the first time- then he did what he warned in advance he would, bringing out some Japanese items which are battery powered, setting four of them in specific places, one on top of the power amp where the power transformer would be, one on the power supply for the TotalDAC-D1, one on top of the inductors each in the low frequency crossovers. We had last been listening for a second time to "Aras" after some small speaker positioning adjustments, and after making this "update", not touching the volume control from the previous listening just a couple of minutes before, listened to "Aras' again.

Previously I had been discussing my plans for further room treatments, addressing possible sources of comb filtering and the like, and relating it to things I normally heard in his system the last time I was there. Well, after he setup his devices, turning them on, we listened again, and if I had been blindfolded, I would have sworn someone had changed out a piece of gear or installed some room treatments, as the focus and integration of depth of acoustic space increased quite markedly for the same piece of music. To use a photographic analog, it's like switching between using a 70-150mm zoom lens on my medium format Pentax camera, with the throw set to 120mm, then switching to the 120mm macro prime lens on the same camera. Yes, the field of view is the same, but the rendering of micro contrast, definition, and depth of view is quite different, and substantially improved to the critical eye. (I could spend a lot of time going into detail about how different lenses render things like micro contrast in center versus edges and depth related chromatic aberration as you go in and out of focus, because the transition to out of focus is not consistent color wise in lesser lenses; obviously, black and white targets are most adept at identifying the short comings, but you see that even in rendering a color image- but this isn't the place or time for such a lengthy divergence. If you're not a bit of a photography nut, you'll just have to trust me on this one, I guess.... )

So, these devices just render things more in focus- that's the easiest way to describe it, considering the contrast and interaction of instrument envelope wave shapes and harmonic timbre. The claim is they reduce EMI. Do they? There are some tuned RF absorbent structures internally, and some active circuitry- he had some of our RF applications guys look them, but they don't really have a clear idea of what this is doing or how it works, or how to test it, other than listening.

My colleague is always on the look out for things like this, and has tested and rejected quite a few, but kept some of them- his wife, a physician, is also a music lover, though probably almost as skeptical as I am, but does endorse the "tweaks" they've kept.

We went back through several more cuts, never touching the volume control, and turning them on and off. We also went through the DCD8 configuration menus for about 10 minutes, resolved an issue with how the secondary digital domain was setup, and got re-clocking with the 10MHz Rubidium oscillator properly functional, which was most audible on some of the "audiophile" cuts like the Jazz at the Pawnshop "High Life" and Shelby Lynn's "Just a little Lovin'" Considering the state of playback at the end of the afternoon versus the beginning, I would call that a productive session.

So, as I say, I can't unhear what I've heard; I spent some time later in the evening listening alone to a variety of favorite cuts. At least a few of these gizmo's are going into the system. You guys and Lex may want to take a vote and kick me off the moderator role, as I've obviously lost my mind... but what has been heard cannot be unheard. But I won't mind, I'll just be listening to some more music at home...

And then I'll be looking forward to when I have some of my local engineering colleagues up to listen to the Isiris and system, as I've long promised to do.... I'll feel like I'm cheating, because I won't tell them about the tweak units, just let them listen and think it's just my engineering expertise at work...

[5th element]

Well from my point of view I'd want to take those little boxes to pieces and see what they actually do, I mean it cannot be too difficult to figure out what the active circuitry inside actually does.

The first thing I think is why should placing one over the power transformer make any difference or improve things? The presence of the magnetic field is what allows the device to actually function, the same with the inductors and by their nature both the transformer and inductors 'filter' EMI all on their own.

I do know that placing magnetically conductive parts near air cored inductors can alter the inductance quite significantly and certainly enough to cause a frequency response change.

I suppose it's possible that the device could somehow be damping the spikes created by the diodes turning on and off in the PSU of the amplifier, but one can do this properly with tuned RC snubbers if it's going to be worthwhile.

It seems like further investigation is required.

Do you have a link to the little devices?

[chasw98]

Here's another thought....
Since your 'friend' sounded like he thought your system was comparable to his system, which appears to be stratospheric in dollars (or marks), there is a possibility that you have resolved detail in your system to the point that you can actually hear little whizzbangs do things that might be poo pooed and go unnoticed in lesser systems. Since you are usually a "if it can be measured and proven, I will look into it" kind of guy, here you are semi endorsing audiophile goo! A first!

In my opinion, the next step would be two fold. Live with them for a while to see what they are like and in thirty days and rethink your opinion at that point. Second, perform ABX or double blind tests with people you know can pick up the subtle differences that you have now heard and cannot unhear. See what the results are. Neither of these methods will give you an insight into what the little pieces of Japanese Kryptonite actually do or don't do electrically or physically (it might), but it would be a logical step to understanding what might be going on.

[JonMarsh]

That's a reasonable plan Chuck- I was joking with a friend at work that it's becoming more an more obvious, though, that I may need to find a good used Audio Precision System 2 on eBay to buy so I can do some really high resolution measurements of this gear and the total system configuration! It's something I would still feel more comfortable with than just admitting, "Dang, these sound pretty good, can I get a couple more?- but I sure don't know why... "

I've been resisting trying some of the things he's recommended a long time (I remember now I have one of these somewhere at home that he had sent me or left with me a year or more ago)- while I can accept hoo hah big bucks cables, in some sort of sense, IF there are measurable "improvements" in known physical parameters, stuff like this is getting uncomfortably close to Unicorn Tears and the Holy Grail, for me... :W

[JonMarsh]

Well from my point of view I'd want to take those little boxes to pieces and see what they actually do, I mean it cannot be too difficult to figure out what the active circuitry inside actually does.

The first thing I think is why should placing one over the power transformer make any difference or improve things? The presence of the magnetic field is what allows the device to actually function, the same with the inductors and by their nature both the transformer and inductors 'filter' EMI all on their own.

I do know that placing magnetically conductive parts near air cored inductors can alter the inductance quite significantly and certainly enough to cause a frequency response change.

I suppose it's possible that the device could somehow be damping the spikes created by the diodes turning on and off in the PSU of the amplifier, but one can do this properly with tuned RC snubbers if it's going to be worthwhile.

It seems like further investigation is required.

Do you have a link to the little devices?

I argued with myself for quite a bit lat night and early this morning whether I was even going to mention these. My colleague gets them from Japan via a Japanese colleague that works there- I don't know if there's any US sales, and my friend says they rarely come up in Europe. He has had a couple of our RF apps guys look at them, and they sort of shrug their shoulders, and say, yes, there are some tuned circuit elements and a bit of active circuitry, but what they would do and why is not at all evident.

As I mentioned, the whole things smacks to me of X-Files kind of stuff, or alien abduction; that's how weird it feels to me. I do intend to follow up, but naturally, rather cautiously... I wouldn't want you guys to get concerned and arrange an intervention and have me institutionalized!

[chasw98]

What is the make and model number of these little devices? Are they only available in Japan?

[JonMarsh]

For the inquiring minds that want to know, here's one of the published reviews/writeups I'm aware of...

http://www.positive-feedback.com/Issue40/acoustic_revive.htm

Here's their web site in English:

http://www.acoustic-revive.com/english/rem8/rem8_01.html

They can be found on eBay from vendors in Japan. Typically around $440 or a bit more. Not an impulse purchase unless you're a lot more affluent than I am. I think I have one at home that my friend previously sent me... this has prodded my memory... maybe I'll pick up one or two more to start... but I'll probably keep a low profile on this, including with my GF! ;-)

Another write up.

http://www.stereotimes.com/MW2008d.shtml

Obviously, whatever it is that they truly do, it's likely that's it's more worthwhile in a fairly transparent system- possibly the better the system, the greater the subjective effect. But how and why, I dunno...

[5th element]

All I keep thinking when I look at those reviews is that there's one born every minute. I mean if that thing, being battery operated, is going to stand a chance of actually being able to actively cancel any magnetic field produced by whatever's producing it, then it would need to be able to put out a pretty strong field.

I mean I can get the whole, it could have a sensing coil and a 'power' coil and that it could be configured in such a way that it attempts to oppose any field that it is put next to, but that'd require some serious power and not something you'd manage with a couple of small batteries.

Still I remain open minded and I'd be interested to see what they actually do. I mean they must do something right?

[5th element]

Obviously, whatever it is that they truly do, it's likely that's it's more worthwhile in a fairly transparent system- possibly the better the system, the greater the subjective effect. But how and why, I dunno...

I'd have thought it'd be the exact opposite. You'd figure that with expensive gear that it would already have been designed to A) Not put out any EMI and B) be designed so as to not be susceptible to it.

I mean cheap gear would need to be stable, be able to pass EMI regulations, but beyond that the SMPS that are often found inside naff gear could contaminate all sorts of stuff inside, of course placing a small thing on the outside of the case isn't going to fix that either, a circuit/layout redesign would, but hey there's the chance that some externally placed device might help in those instances. It might not cure, but it could reduce.

[JonMarsh]

Very reasonable arguments, and ones I find quite plausible, as an engineer.

On the other hand, was has been heard can't be unheard.

A Danish colleague of mine who used to work for someone else I've know for almost 25 (Eric Mendenhall)years due to mutual activities in the AES back then, regarding class D amplification, and who is now a very knowledgeable designer for Class D equipment himself, doesn't believe it's possible that speaker cables can impact the sound at all as long as they are of some reasonable DC gauge. Is that your experience? It's not mine. What we believe is possible is certainly guided by past experience and belief structures; I didn't previously believe what I heard yesterday was possible. I'm not sharing this info to get you to buy any of these widgets, but just to remind you that things may exist or be possible that we don't predict or ken based on past experience.

[5th element]

Is that your experience? It's not mine. What we believe is possible is certainly guided by past experience and belief structures; I didn't previously believe what I heard yesterday was possible. I'm not sharing this info to get you to buy any of these widgets, but just to remind you that things may exist or be possible that we don't predict or ken based on past experience.

Well I think one has to look at the overall properties of the cable before jumping to any conclusions. Simply looking at the DCR of the stuff might not be enough as the capacitance of some cables can trouble some amplifiers and degrade their phase margins, pushing them to become unstable. On the whole though, yes, I would say, given a thick enough lump of copper, that's all you need for a loudspeaker cable. I can dig the whole silver plating business though, as silver does have lower resistivity, so for a similar gauge, the silver cable should give better results. Also the cable geometry and how the paired conductors are arranged could reduce EMI radiation when connected to some amplifiers and on the flip side affect EMI induction into other amplifiers that could again cause instability and affect the sound.

I think though, that when people say things like 'it's not mine', with regards to subjective experience that these things need to be taken with a grain of salt. It is reasonably well known how gullible we are when it comes to our minds being tricked by these types of things and a properly conducted double blind test, as annoying as it is, would really be the only way to see if you can actually hear the differences you claim to be hearing. I mean some people get annoyed when people say that it's all in your mind, like it invalidates their subjective experiences in some way, but that's just reality, we are human and easily fooled, even by ourselves.

I'm open to trying different bits and bobs, different component types and qualities, but only if it doesn't cost a fortune. What I see is companies out there trying to squeeze money out of people where money really shouldn't be squeezed. If boutique parts and wires were actually important then they'd be a part of every wholesale retailers parts inventory (such as mouser/digikey/farnell etc). If these special parts were needed for technical specifications to be met, or for highly sensitive pieces of equipment to actually meet their performance criteria, then those boutique parts would be readily available, but they are not.

If the widget cost £10 I might buy one to give it a go, but I think it speaks volumes about it when it costs ridiculous money. Clearly someone is hoping that someone else will like glowing subjective prose enough to actually spend that amount of money on one.

[Steve Manning]

Jon, what's the case made of?

[JonMarsh]

Plastic of some type- not metal.

[dar47]

Come on Jon! Lets get back to the Engineer in you, Haha

I have Meniere's disease, or(syndrome more like it) my hearing changes very quickly even minute by minute . Some days I feel like I can hear as well as a blind person with increased sensitivity that has shown up on a test day with the ENT doc. Other days I'm living with a train in my head. Your ears and brain are a 100 times more complicated then all of the best gear staked up and Doctors still don't understand much especially when things go wrong with your hearing. I think our hearing and brain can do a lot of suggesting after all it is electrical and chemical. So for me I have to hear it over time. I would say your trained ear, musical background and vast experience evaluating frequency response can be fooled on any given day with your hearing changing even minute to minute.

Would be nice if we could plop these gizmos down in a less then perfect setup room and get some positive result but at $400 a pop I'm out.:B I say have some fun with it but don't let keep you up at night.:lol:

[JonMarsh]

Good thoughts, there... as I said, I'm certainly not advocating these for anyone, but having played with them a couple of evenings now, and realizing I already have one at home (previously sent, not tested out of incredulity) I'm just going to quietly do my own thing...

But a big part of that will be getting back to the Ardents! Saturday is booked with mundane things like Dr's appointment and lab tests (routine annual) and a BBQ planned at my Danish colleague down in Campbell. Hopefully Sunday I get can back in the normal swing of things and buff out the other Ardent cabinet and start putting them together! Just have to multi-task that and the laundry.

Well, the other 24V OMRON SMPS finally shipped, worth waiting a bit because it was a good price for a unit removed from unused equipment; then I can get the Mutec running and evaluated soon.

My hope is to have things dialed in with the Wavecor Ardents such that by the long weekend I'm planning on the the 3,4,5,6 of July, I can start the tear down and updates on the Isiris, including the refinishing. I'm looking forward to getting this stuff DONE! :W

[dar47]

Sounds great, I think your making progress on all fronts.:T

I just caught up with the reclockers on the digital posts, sounds promising. I have been considering what to do with music server and interface to the M51. I can't afford the whole NAD vault thing but sure would like to know the cleanest and easiest interface for primarily music off the computer. All in one box or NAS with something in front HTPC? May have to start a thread to get some thoughts going I haven't seen any clear cut winners. It seams like everyone has a different approach.

[JonMarsh]

well, I may be able to give you some more feedback on different approaches- the M50 has a very nice way of working with different types of NAS setups. I bought a LaCie NAS recently, dual drive raid, but like many other things haven't gotten to setting it up yet, but should soon.

I may even do an experiment by copying the M52 contents to a folder on the NAS, or the AIFF processed files from my iTunes ALAC library just as a test case.

Actually, just this week was the first time I used the USB front panel jack, plugging in a memory stick and browsing it for files to play- that worked quite well, I'm just curious to see how much USB power power it will support (for example, using one of my portable 480GB OWC SSD drives, but also I have that cute little dual 2.5" raid box- (I have a second one of those but without drives in it yet).

So, there's LOTs of stuff to play around with and see just how well it works- hopefully I'll be able to find some time in the summer to fit a bit of that in on the weekends-

but for now,

• Job One is finishing assembly and fine tuning of the Wavecor Ardents (for your AND my benefit, so I have something nice to listen to while working on the Isiris)
• Job Two is disassembling the Ardents, updating the midrange enclosure damping setup, and refinishing with lacquer and packaging the crossovers internally
• Job Three is spending more time on the barbecue... and at least one of the bikes!