Newbie Question about Troels 2-Way Choices

Has anyone built one of the following Troels Gravesen designs:

SEAS CA18/RLY/22TAF-G
CA18RLY/22TAF-G

SEAS W15CY001 + HIQUPHON OWI:
W15CY001-OWI

SEAS CURV
SEAS CURV

Ellam XT
Ellam-XT

Troels is adamant about not commenting about differences between his speaker designs so I'm checking if anyone has ever tried any of these and, if so, how did you like the outcome? I'm leaning toward the SEAS W15/OW1 design as it looks like is has the best quality drivers and I already have the tweeters.

I am looking for a simple project for a second pair of speakers that have a conventional flat front baffle (for aesthetic reasons). I'm seeking a speaker that would not cost too much and would be relatively easy to drive with an EL34 tube amp or small solid state (such as a gainclone). Any advice or comments on your own building experiences related to any of the above speakers- or others I should consider- would be most welcome.
 

anji12305

Member
2006-01-25 1:59 am
Has anyone built one of the following Troels Gravesen designs:

SEAS CA18/RLY/22TAF-G
CA18RLY/22TAF-G

SEAS W15CY001 + HIQUPHON OWI:
W15CY001-OWI

SEAS CURV
SEAS CURV

Ellam XT
Ellam-XT

Troels is adamant about not commenting about differences between his speaker designs so I'm checking if anyone has ever tried any of these and, if so, how did you like the outcome? I'm leaning toward the SEAS W15/OW1 design as it looks like is has the best quality drivers and I already have the tweeters.

I am looking for a simple project for a second pair of speakers that have a conventional flat front baffle (for aesthetic reasons). I'm seeking a speaker that would not cost too much and would be relatively easy to drive with an EL34 tube amp or small solid state (such as a gainclone). Any advice or comments on your own building experiences related to any of the above speakers- or others I should consider- would be most welcome.
I've built the Quattro II.
Troels' JA 8008 driver is a marvel.

It has a broad bandwidth, which allows a crossover to the tweeter to avoid artifacts in the range of voices.

In my opinion his designs are strongest for the extensive testing of real crossovers, to verify simulations.

One caution; I prefer frequency profiles which favor midrange response and 'tilt' downward as frequency rises.

Troels' voicing scrupulously attempts to make neutral the response of his chosen drivers.

If you make your cabinets stout, with few resonances, they may come off a little sterile, as did mine.

******

I part company with Troels in that I think tweeters should be driven to the lowest practical point in a CD guide.

My current 2 way crosses over to the tweeter at 1250 Hz.
(27tffc/H08rw) 2nd order LW.

My suggestion would be to build any kit with a decent LPad parallel to the tweeter. Getting the final balance between HF energy and the rest makes a real difference in satisfaction.

It's the bottle of Sriracha sauce on the Taqueria truck: some prefer a little, others favor more.

Sent from my HP 10 G2 Tablet using Tapatalk
 
Since you already have the HQ tweeter, go for SEAS W15/OW1. The driver integration with the crossover looks good, the metal cone peak well taken care of (but pay attention to the exact value of the coil in the 8 Khz notch, it should be 0,30 mH precisely).
The impedance and el.phase also looks flattish so should work well with tubes.
 
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If you are looking for a very nice Troels 2-way design, he used to have two different Scanspeak mini-monitors on his site that are no longer published: 15W8535-K00+ 9700 tweeter and 15W8535-K01+9500. Perhaps if you email Troels directly he will send you the design: he has built more speakers then the ones that he has posted on his site.

I built the one with the K00 mid and the 9700 tweeter, I think that it is called the “Scanspeak Shuffle,” and really liked it. I found that it imaged really well, worked with a mid range of amps, and was overall well-balanced and neutral. I am personally partial to the Scanspeak drivers, particularly the 15W8535K00. I suspect that the SEAS 15W0W1 might give you slightly more detail and would be very neutral but the SS mid would have more bass and also very clean bass.

Of course, if you have room to build the Quatro MKII I suspect that design would be worth the extra investment. I have not heard it but I have heard very good things about the driver and Tony Gee uses it on his latest high-end speaker.
 
Since you own the Hiquphon OWI tweeters, I think you should use them. :)

Paul Carmody used the Scan-Speak 8530K00 in the 15L Carrera:
https://sites.google.com/site/undefinition/carrera

Troels uses the SEAS CA15RLY in 12L here:
SEAS 5INCH

IMO, a 7L box won't do well here, poor bass:
W15CY001-OWI
As well as a more complex crossover for the metal driver.

The CA15RLY is a lot cheaper than the other two drivers, and flatter impedance which can be further improved with that 0.26mH/33uF/8.2R LCR.

FWIW, I compared the (dotted) Carmody 15W and Gravesen CA15RLY 3kHz crossovers with similar drivers, a bit of mix and match. They are effectively identical except for choice of tonal balance. Easy project, but not the cheapest crossover in parts. That 5.6R will probably be 3.3R with the less efficient OWI.
 

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Since you own the Hiquphon OWI tweeters, I think you should use them. :)

Paul Carmody used the Scan-Speak 8530K00 + OWI in the 15L Carrera.

I have not heard the Carrera, but the measurement data suggests system7 found a top design for you to clone, and save design time and passive part costs. I would move the port from the rear to the front baffle to allow against-the-wall placement as used in a desktop monitor.

Still one of the best... slit paper cone....
"The Scan-Speak 8530K00 'Revelator' is a phenom of a woofer. It has excellent bass, a near-perfect Frequency Response, and a midrange that is comforting in a way that only a paper-cone woofer can deliver."
 
Oh, that Carmody Carrera design is very nice for a 5", but what a cost!

The other way to go with this splendid little tweeter is an 8" bass. Look up the Monitor Audio R352 and you will find it has been done before. I tend to use third order negative polarity tweeter a la KEF, a sort of butterworth.

So the below sort of design is pretty good and the sort of thing I listen to with cone tweeters. Minimal filtering on the bass. I thought a H1288-08 CA22RNX might work well in closed box around 20-30L.

It can be made very valve friendly with a bit of impedance correction. Here simulated with a 6R resistor. Ah, it's a great hobby. :)
 

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Hi all and thanks very much. I was completely unfamiliar with the Paul Carmody Carrera but it seems like an excellent suggestion on a number of levels. First, I can use the OW1 tweeter that I already have. Second, it employs the Scan-Speak 15W8530K00 that others have raved about in other designs. I also like that the cabinet is a bit larger to give the bass a bit more support while still being small enough to use in a second system in different settings and future applications.

I did consider the Troels' Revelator 4R kit but was worried that the 4 ohm woofer would be harder to drive for what I now have and what I might build in the future (I'm interested in trying a Pass F6). I particularly appreciate System7's suggestion to look at the Paul Carmody Carrera as I had not previously heard of the design or the designer. I was originally just using Troels' designs for the short list as they all seem well-proven, but it was great to find another design that uses similar quality drivers and a tweeter that I already own. I don't mind paying for the Scanspeak 15W8530's as I am very slow at wood working and at the end, I really just want to be sure that all the effort pays off with a speaker that I will be able to enjoy for a long time. I think that once I get a bit faster at making cabinets, I'll be more open to experimenting with other designs. Thank you all again for your comments and suggestions- they have lead me to what I believe will be an excellent choice!
 
Marvellous! A fun-project IMO. frangus suggested it first, of course. You must tell us how you get on. :D

Being DIY, if you don't like the balance, you can change it. You'd just change the 1.5mH to 1mH for less bassiness. And change the 8R (well, use 8.2R) to a brighter 5.6R and get more Troels-like balance.

Because we are at the cutting edge of speakers here, there is a current theory that good flat impedance makes life easier for ANY amplifier. So I looked into that. Of course, reflex is hard work without feedback, so you must take your beating with a high impedance valve amp.

Some impedance correction is easy enough. I particularly like the top-end HF work, which here I calculate to be a 15R + 1uF Zobel adding the 9R in the filter to the tweeter parameters, maybe across the speaker terminals.
Impedance Equalization (L-Pad) Circuit Designer / Calculator

Believe me, it civilises the sound of a tweeter into something smooth.
 

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That Zobel value I calculated was nagging me. It seemed too big on the capacitor compared to stuff I do myself.

Turns out I got the decimal point wrong on the Hiquphon Le of 0.03mH with 15R.

15R and 0.1uF is correct. That's tiny and similar to the sort of Zobel a lot of amps have at the output. But still worth a try IMO.

Good Carrera build ongoing here: http://www.diyaudio.com/forums/multi-way/283362-paul-carmody-carrera-build.html

Looks nice, so far.
 
Thanks System7. I appreciate your advice on how to change the tonal balance on the crossover. I just found a used pair of 15w8530K00's in very nice shape- looks like only one of the pair was actually hooked up- so I'm looking forward to the build. Also picked up some purpleheart wood for the baffle and have to think through the aesthetics a bit more before I begin. I was thinking about purpleheart and walnut veneer.

Anyway, I'm really happy to find a used pair of mids and I appreciate the suggestion for this particular design as I would not have come to it on my own. Will post updates as the projects comes together.