Anyone have experience with the Carmody "Spitfire" kit or the Sobie "Blues" kit? Both use HiVi woofer but different tweeters

[cavedriver]

Looking at these two kits for an easy bookshelf build. They are very similar with the main difference being the SB tweeter in the Blues vs the Airborne tweeter in the Spitfire. Also, thinking of using the Denovo knock-down cabinets from Parts Express- any warnings there? I don't suppose either has been put on a Klippel by anyone?

One moment, please...

One moment, please...

 

[moonlight rainbow dream]

I would personally avoid these two designs even though I have no first hand experience. This is because, even if the crossover and on-axis frequency response is executed to perfection (which is not a given; check out Erin's measurement of Carmody's Overnight Sensations), the directivity mismatch between the midwoofer and tweeter are not addressed. These will exhibit the typical off-axis "bloom" in the crossover region; ~1.8-3khz in typical 6" 2-ways. You can EQ in a "BBC dip" to make the sound less offensive, but then the on-axis response is flawed. Once you have lived with a speaker that nails both directivity and frequency response, you won't want to go back to one that doesn't. In that regard, I can enthusiastically recommend the parts express C-note, which makes use of a waveguide tweeter. That design has been measured by Amir.

 

[cavedriver]

I would personally avoid these two designs even though I have no first hand experience. This is because, even if the crossover and on-axis frequency response is executed to perfection (which is not a given; check out Erin's measurement of Carmody's Overnight Sensations), the directivity mismatch between the midwoofer and tweeter are not addressed. These will exhibit the typical off-axis "bloom" in the crossover region; ~1.8-3khz in typical 6" 2-ways. You can EQ in a "BBC dip" to make the sound less offensive, but then the on-axis response is flawed. Once you have lived with a speaker that nails both directivity and frequency response, you won't want to go back to one that doesn't. In that regard, I can enthusiastically recommend the parts express C-note, which makes use of a waveguide tweeter. That design has been measured by Amir.

The Spitfire uses an AMT-type tweeter. Wouldn't that be likely to mitigate the mismatch (or make it worse?). Also, it's odd that each of these designers speak of these designs as among the best they've ever made. I know they have a product to sell but it's curious they aren't a bit more circumspect. Both surely understand directivity. But your point is well made.

 

[Wolf]

Both of those kits are about 10 years old or so. I have heard both.

The Spitfire was someone else's build, not the designer's, so you can wonder if something was missed. According to the design, it was supposedly built faithfully. That said, I feel the tweeter needs amplitude reduction. I can't estimate or guide further until that is resolved.

The Blues kit is a good entry level design that does not cost much, and can be cranked on if desired. I find it to be benign and neutral, to the point where clarity and transparency are not it's best qualities. It does the job applied for and does it well; smoothly nonfatiguingly.

If you are stuck on a HiVi woofer, want good polar response, and can spend a little more, than my Nephila design is likely where you should look. I felt they were very good when I built them 8 years ago, with props from the judging at MWAF, Jeff B going out of his way to write a review, and now some new information that has come to light in the past couple weeks.

They passed hands through Robert "Brian" Clark to Bill "4thtry" S, who is now the current owner. Bill has recently been guided into nailing his polar measurement technique, and wanted to know what made these sound so good to him.

To sum it up, their measured directivity is absolutely fantastic, and measures better than anything Bill has measured to now over the last few years. That said, at one meter there is a bit of a bump in the treble, but measured further away it disappears.

If I can figure out how to scan and post the paper copy images, I will do so.

 

[Wolf]

As promised, I was able to scan the docs in. (We got a new printer, and I had to learn how...)

Like I said, the bump at 4.5kHz appears at 1m distance, but goes away at 2.5m+. The rise is there in the top-octave because they are shorter towers, and listening will likely be just above the tweeter axis. Being that the AMT is longer, the vertical window is pretty narrow, so I had to target above the standard on-axis for doing the xover modeling.
Sorry that the images are turned, but your standard .pdf viewer will rotate them easily should you need to.

 

[Wolf]

These are better, Bill sent them to me:

EDIT: Bill apparently plans to redo these in a week or 2, stating that the validation method he used was not totally proper. The rise above 3k is not real and is due to the methods he used this time. I will update when these are redone....

 

[cavedriver]

If you are stuck on a HiVi woofer, want good polar response, and can spend a little more, than my Nephila design is likely where you should look. I felt they were very good when I built them 8 years ago, with props from the judging at MWAF, Jeff B going out of his way to write a review, and now some new information that has come to light in the past couple weeks.

To sum it up, their measured directivity is absolutely fantastic, and measures better than anything Bill has measured to now over the last few years. That said, at one meter there is a bit of a bump in the treble, but measured further away it disappears.

Yes, the HiVi woofer was what I was looking for. I believe they are the mids being used in the Von Schweikert E-3 Reference Editions which I've heard and really liked (but cost $20k+). The strange part is that Swan no longer lists this driver on their web page although it is still available on US websites. They apparently had introduced an 8" version in 2019 but have withdrawn that from the market already (an "LK8"). I think I saw a post where you commented on it. Might have been an interesting driver. I hope Swan doesn't discontinue the L6.

My thinking on the Spitfire/Blues kits is that I could build them quickly and cheaply using the Denovo bookshelf cabinet and if I wasn't 100% satisfied with them I could use them as either the sides or height speakers in my movie room. I have some sides in their that are way too narrow in their directivity right now so these two kits might not be enough of an improvement. The Nephila is interesting but is clearly more work to get right, and would be a tower so I could only hope to use it for the sides if it doesn't stay in a 2-ch listening room like the library. Ideally what I'm looking for is a bookshelf with wide, smooth directivity.

 

[Wolf]

Okay, now I see that you want the bookshelf version of the Blues. There are towers available as well. With regard to the Nephila in comparison, they can be built as bookshelf cabs, but the extension will be cut to meet volume requirements. That said, as long as the width is the same, and the tweeter same distance from the top, then this is quite doable. Mudjock/Scott Sehlin also used the F6 in a bookshelf alignment, so that would be a good place to start.

I have heard the same E-3 Reference, and also the previous version that was sold by Endeavor Audio. VS bought Endeavor out, changed the tweeter, and dramatically increased the price. It also has a pair of Dayton RS180 woofers for the low end.

I remember the LK8, and it looked great! I just never saw anyone use it....

It is a matter of taste whether someone favors the HiVi F6 or the HiVi L6. The L6 seems to be more damped and neutral, but misses some of the clarity at times, as carbon fiber can do this. I like carbon fiber, and glass fiber driver derivatives a lot, and some are just better than others. The F6 has a glorious midrange quality and retains a lot of the subtle details in sound reproduction, likely due to being Kevlar/paper based. It depends on which camp you are in.

 

[Wolf]

Oh- and it seems like HiVi is in a state of revamping products. The M series now all have damped black cones for example. I'd hate to lose the L6 or the F6 in terms of availability.

 

[cavedriver]

I have heard the same E-3 Reference, and also the previous version that was sold by Endeavor Audio. VS bought Endeavor out, changed the tweeter, and dramatically increased the price. It also has a pair of Dayton RS180 woofers for the low end.

Yeah, apparently the Endeavor lead, Leif Swanson, worked at VS first, then left to form Endeavor, then sold Endeavor to VS and is now their lead designer. To bad the prices have gone up so much. I had convinced myself that the SE's use a Seas Prestige woofer driver, but $120 a piece it's hardly more expensive or high end than the Dayton it might have replaced:

Edit, this ~175 mm Seas is what I meant:

SEAS Prestige L18RNX/P (H1224) 7" Aluminum Cone Woofer

6.5" High Fidelity woofer with aluminum cone, phase plug, and an injection-molded metal chassis, intended for bass reflex and transmission line designs.

www.madisoundspeakerstore.com

 

[Wolf]

Nope, they are RS180 woofers. The phase plugs on the L18 are huge by comparison.

 

[cavedriver]

Nope, they are RS180 woofers. The phase plugs on the L18 are huge by comparison.

yeah, looked some more at pictures, you must be right. Combined with the Scanspeak Be tweeter and Fountek rear tweeter, that's about $1600 in drivers in a $22000 speaker. Kind of makes you want to do more DIY, doesn't it? Maybe I'll buy one of the kits and then play around with different tweeters until I get something I like.