The "Elsinore Project" Thread

Ansar? :unsure:

Yes, it is Audyn True Copper Max. I thought for a moment that there had been a name change?

As I mentioned earlier, I have a preference for real copper capacitors, when it comes to the Tweeter, so both Audyn True Copper Max and Miflex KPCU-03 are in that bracket. Have I formed a preference between the two? No, not yet and if I do I will pass that on.

Then there is price and dimensions and fitting onto the Black PCB, so that it can fit through an aperture 145mm in diameter, the bottom driver hole and fit at the bottom of the box. The True Copper Max is 50mm in diameter and the Miflex is 40mm. But the Miflex is a bit longer. Both are a challenge to fit, but the Miflex is just ahead.

I have one question. As far as I can see, there is no RLC trap on the schematic for the break-up of the aluminum diaphragm of the Sba 17 NBAC loudspeakers. Is this solution a certain compromise of the crossover, or is it simply your opinion that this break-up is not audible?

And that is a good question and occupied a lot of time with me. Based on my theory re external 'linear' inductor suppressing the internal 'non-linear' inductance of the driver, that this is the key to making the driver respond better to the current of the amplifier (this is central to a paper we are writing) and we get the same current-drive benefits that has become such a hot topic in more recent years.

Current-drive is really the ratio of the source of the amplifier versus that of the driver should be 5:1 (or as close to it, or even higher ratio).

The same effect as current-drive can be gotten by using the same ratio of 5:1 or higher, but use inductance as the ratio.

Is this just theory? I don't think so. Call it inductor-drive if you like. It suppresses the non-linear inductance of the driver in the same way that normal current-drive does. That is simply how it works.

So I almost doubled the external inductor, played around with the so-called 'BBC dip' in the response (promoted by the likes of Lynn Olson). Besides, what I already do also lends towards that BBC dip. So increasing it from 1mH to 1.8mH and adjusting things around that, the need for that LCR (or RCL) trap receded, which interferes with what we want the series inductor to do.

Re this SB17NBAC driver, it is that the breakup is incredibly mild for an aluminium driver. Even Troels Gravesen realised that when he used his Clio setup (similar to my Clio setup) and used the MLS signal option. The MLS sound like a noise and when you feed that through to a 'hard' cone like aluminium or magnesium etc, you can hear that metal zing. This NBAC driver did not have that sound and he initially thought he had made a mistake, but he had not. Read the story for yourself.

"Usually you can hear from the very MLS signal if a driver is trouble or if it's smooth on the ear."

http://www.troelsgravesen.dk/SBAcoustics-61-NAC.htm

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Polyprop is "MFC" and aluminium is "NBAC" and paper is "NRXC." In fact, Troels says the aluminium is better than paper, just.

So the end result is a BBC dip that seems to work very well. The much larger external inductor is now 1.8mH and the combined inductor 2 x NBAC in series is 0.3mH. I class anything that gets to 5:1 as the same as current-drive and here we have 7:1 in total. And that larger inductor also nicely means I can get by not using the LCR.

I never thought, never ever, that I would be doing an aluminium or 'hard' cone version of the Elsinores. This NBAC driver changed that.
 
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Greetings from Skagway Joe... I thought I'd check in after I "logged out" due to the constant needless pushing of ideas and arguing by others. I'd just finished my project sheet for the Elsinores, the MFC version, priced it out, sourced suppliers, only to find there's another version :unsure:. Don't get me wrong, choices are good, but add a layer or two of complexity to my decision making. The NRX is not available, the Purifi too expensive, the MFC seemed fairly "goldilocks" 👌. It would seem the NBAC's are in the same ballpark as the MFC so there's a decision to be made.

Question is, how does one decide between MFC or NBAC without being able to compare them? Are there distinct differences between the versions? Sonically, sensitivity, from an amp matching perspective, distortion, other measurements, enclosure size (same?) etc.? I'm curious.

By the way, appreciate you sharing all this hard work freely. The amount of times I'm looking at an interesting project where the builder conveniently leaves out crossover information are numerous. I truly appreciate the position you've taken.

All the very best,
Ron
 
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Super, I'm sure the ULD's will provide lots of listening pleasure. They're out of my league currently, I need a full system replacement and they'd absolutely devour the budget :cry:. I like the Elsinores for quite a few reasons, due to my history in speaker building it's the crossover topology and the fact that the same units cover bass and mid, that attracted me to Joe's design initially. So I'm there, but have to choose, NRX, MFC or NBAC.
 
Joe,

I will look forward to your impression of the relative performance of the Audyn True Copper Max vs Miflex KPCU-03. Since I already have built my crossovers with the Audyn, I will keep with what I have…I am starting my ULD build in July, having the Purifi drivers in hand and ready to start one I pick up another sheet of bamboo plywood.
 
Greetings from Skagway Joe...

I assume Canada?

I tend to recommend the MFC for its all-round capability. The ULD is of course the RR choice, but not exactly affordable. The NBAC is more a specialist version, it does not have the same high sensitivity of the other two and the other two works with nearly all amps that there is. Yes, I have a 6 Watt amplifier to check that. To me the NBAC has the kind of elements that I hear in ribbon speakers, which some have a taste for. So I am not sure what else I can say.
 
Super, I'm sure the ULD's will provide lots of listening pleasure. They're out of my league currently, I need a full system replacement and they'd absolutely devour the budget :cry:. I like the Elsinores for quite a few reasons, due to my history in speaker building it's the crossover topology and the fact that the same units cover bass and mid, that attracted me to Joe's design initially. So I'm there, but have to choose, NRX, MFC or NBAC.

Again, with still available drivers, not much to fault re MFC.
 
Actually all around Alaska and the pacific these past 3.5 months. But yes, the days are getting longer and longer up here. On my way home now though, I live a little south of Pilsen, in Bohemia, Czechia. I'm moving house, where a new cavernous living room awaits.

I remember a photo of older versions of the Elsinores at the Audiophile Society of NSW, where they seemed to play successfully in a huge room. This lead me to go down this road, after having traveled many others, both in concept and price-range. The more time I spent on researching and putting a project sheet together (I tend to use Excel spreadsheets, the different tabs, to put all relevant information in some kind of order) the more I liked it.

There's always a risk when building something new, especially when you've not heard it. So to have something that is of obvious great value, especially with current prices of all things audio, and has been worked out in such detail, and enjoyed by many is quite precious. I'll start with the MFC this winter, this summer is all about moving and settling in.

But again, I appreciate you Joe, for all you do, your willingness to put yourself out there and discuss, debate, defend, your ideas. I was a bystander in this thread, and I had hard time with a few of the "participants" who were trying to get you to do, think and act as they do. I wouldn't have the time, the patience or the crayons to explain myself over and over again.

So thanks Joe, I'll be sure to put some pictures of the process once I get to that stage.

Speaking of Skagway and Pictures: I took this one of the "Flower Moon" in Taiya Inlet about a week ago, right outside Skagway. The other one from behind the bridge wing of the Aurora Borealis, between Skagway and Glacier Bay. Fairly off topic, but it never hurts to share a bit of the beauty out there...

Flower Moon Skagway Alaska.jpg
Aurora Borealis Skagway Alaska.jpg

 
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Lovely! And thanks for your kind words. Settle in and good luck on the project.

I do love photography myself. In the summer of 2014 I went up to the northern part of Norway, well above the Arctic circle and only just before midnight I took this picture:

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My younger brother moved to Norway around 1980 is is now a nationalised Norwegian. We are three brothers, but live in very different parts of the world, from oldest to youngest:

Flemming Palle Rasmussen - Denmark
Bjørn Ingolf Rasmussen - Australia
Jannik Bloch Rasmussen - Norway

That's me in the middle. Funny names, eh? I plan to be an Australian citizen later this year.

I also love photography and so does my Norwegian brother Jannik.

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Wine and photography, such a common set of interests among among so many Audiophiles
.
 
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Beautiful photographs Joe, the colors are beautiful and the image depth is quite extraordinary. The landscape resembles Alaska.

And those are some interesting names indeed. Mine, Ronald Bontenbal (only my mother called me Ronald) isn't as interesting, but has an interesting history. The below is 13 generations removed, but I'm a direct descendent.
Claes Michielsz. Bontenbal

Having been at sea for a quarter of a century my nearest (funny term) and dearest live all over the world, on every single continent, literally. My family is originally from Zevenhuizen and Rotterdam in the Netherlands, I live in the Czech Republic with my (Czech) wife and daughter. My closest friend is German etc. etc.

And as for wine... it's a part of the music listening experience. Bold and full bodied please.

Anyway, nice to chat, back to packing. It's time to go home.
 
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Joe, there seems to be a typo on your crossover. With R2, L4 won't be able to handle 20W.

The R2 is 2 x 10W. If extreme high power, then use up to 60W (triple) and an inductor with 1R DCR (1/3rd) to cater for that. But maybe go for an external crossover in that case, it may be a bit more of a challenge to do internal.

Beautiful photographs Joe, the colors are beautiful and the image depth is quite extraordinary. The landscape resembles Alaska.0

Key to both photos, 16mm wide angle, F8 and DOF everywhere if not close focus.

Having been at sea for a quarter of a century my nearest (funny term) and dearest live all over the world, on every single continent, literally. My family is originally from Zevenhuizen and Rotterdam in the Netherlands, I live in the Czech Republic with my (Czech) wife and daughter. My closest friend is German etc. etc.

My wife is Italian, more than that, Sicilian, with temperament to match. :giggle:

So our three boys are half Danish-Italian-Australians. The middle one is very fair like me and look Scandinavian.

In our family nobody has lost their heads yet. Danes might know about Carl Bloch, he is quite an artist and we are descendants of his brother Oscar Bloch who was personal physician to King Frederik 8th.

I mean, of course, the SB17CRC

Heavier Cone, lower sensitivity. The box would benefit from a larger volume. I have another thought, the ULD is so expensive and there is one of the Satori drivers that would work well, the MW16P-8. I have already done a 2-Way non-DIY based on the 7.5" MW19P-8 and it works great. If somebody came and commissioned a Satori driver based Elsinores, I might get interested.

MW16P-8​

 
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