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Ha nice play on the name , couldve been muskie ?~?~ Is that a Vifa woofer down low?
The Northern Pikes were a band from my home town, they were a big deal when I was growing up.
It's an AMT3-4 on top, a Wavecor WF120BD03 in the middle, and a Vifa M26WR09-08 on the bottom. Around back is a CSS APR-12. They're playing together very well
The baffle is African Mahogany with Maple accent, and maple veneer on the sides.
The as-designed responses:
Crossover transfer function:
Impedance:
I haven't decided if I'm going to keep the slight rise in the top end, I put that in as I wanted to combat the directivity of the large AMT to some extent. I listened to a lot of music today and wasn't put off by it, so at this point I'm leaving it as-is.
That little bump up top is like what the BG neo's have. It looks worse than it sounds and if you try to squish it, it kinda takes is "breath" away. Nice speakers! I like that shape and the old school Vifa😎👍🏻
Those look fabulous. That maple inlay in the baffle is nice touch. I'll bet they sound as good as they look!
Very beautiful and challenging (for me at least) build.
The inlay was the last thing to do, I nearly chickened out and didn't do it at all for fear of ruining the baffle, but I took a chance and it payed off, and the process wasn't that hard either. There are little flaws at every part of the process, but that's just the hand made character
If you can build a rectangle with mitres corners, you can make shapes that have angles that aren't 45 degrees as well. I had contemplated how I was going to clamp it together and keep consistency, so what I did was build a couple frames out of scrap, then clamped everything to the frames for glue-up, and used the frame as a template for the rear panel.
The biggest failure of this build was the veneer. My first time veneering and I did the iron on method which I don't think I'll be doing again, it'll be contact cement from now on. The wood shrinkage when you hit it with heat caused a lot of checking/splitting that I had to hide. The first large panel was a failure, and I was able to correct my process a bit for the remainder to not have significant splits, but there are small ones throughout. The major splits were carefully patched, from a distance you don't notice it, but when you get closer..."She ain't pretty"
Here's some photos of the build process:
https://photos.app.goo.gl/hQLcTXzemobsVgCE8
Picked up that old Vifa some time ago when Saabracer won the speaker lottery and filled his house with 1000 drivers. I was shopping for the modern Scan-Speak Discovery equivalent, but he gave me a fair price on some NOS M26 drivers. They were brand new drivers that had just been sitting around for who knows how long, and my measurements of them matched the data sheet almost perfectly on all counts, they're impressive!
Nice set of pictures! Beautiful baffle and inlay work! Crossover appears to be about 470. How much BSC did you apply?
Pretty much none at all. If you look at the design responses above, you can see the transfer function of what is applied to the woofer. The resulting designed response was generated by splicing near and far field woofer data without applying the baffle diffraction to the near field response, I directly spliced it without modification. I like how it sounds, and the simulated response is 1-2dB above the midrange, so my conclusion for BSC in this case would be 0-2dB by your preference.
I'm contemplating dropping the tweeter level by 1-2dB, still listening some more before I make that decision.
More of the same of what I posted in the "measuring speakers" thread. If I measure this speaker at the same distance I used for all the design work, 82cm, the gated response isn't that exciting. In fact based on this measurement you would expect the speaker to sound very bright and shouty. This close mic distance doesn't capture the woofer response very well, additionally at this close distance puts the woofer a fair bit further from the mic than the midrange and tweeter which also lowers its SPL relative to the other drivers.
I didn't get out the protractor, just eyeballed the 30 and 60 degree off-axis measurements to confirm the directivity.
Now, if I back up the mic to my listening location a few meters back, the measurement has changed dramatically. Here I have gated response in green, and the ungated room response in red. Wiggles in the green plot from the coffee table. This more accurately reflects what I hear when listening to this pair.
I always use iron on veneer, but that is with paper backed veneer. Works well for me, but I think I've heard that it's not good for raw veneer. Still, the end result for you is effing great.
Yes, if it was paper backed I think it would have been fine for ironing. Happy with the end product regardless, the baffle draws your attention away from the sides
Looks pretty darn sweet to me.
I'm no veneer expert but I can share some experiences with you. I've had failures of veneer of most every method. I don't have a vacuum press so never tried that. The iron on didn't work for me at all, but I suspect that I never got the veneer hot enough. I was always afraid I would scorch it. Contact cement has given me mixed results. I once used latex based contact on a project. After a couple of years it delaminated with seasonal changes in humidity, and I still haven't figured out a way to repair it. I doubt I'll ever use it again. I had great luck with solvent based contact cement. That has stood the test of time and some awful storage conditions. For that I used Barge's cement which is sold for leather work, but a veneer book had good things to say about it, so I tried it. Those have been my most successful veneering experience. There are other brands of solvent based cement I have not tried, but I have been very pleased with the Barges.(That project was a double ply veneer over MDF on a curved baffle.)
Those look great, nice work! What do you think about that Wavecor Mid?
@dcibel I use this contact cement - have had good luck with it - I get it from Windsor Plywood. How are the forest fires around your area this year?
Thanks, yes Windsor plywood is the local shop here, next time I do veneer I'll have a look for this stuff.
We had some smoke rolling through last week, but besides that it's been just fine. A lot worse in the south in Penticton. It's been a very cool summer this year.
It's great!
That's good - we are headed to Lytton tomorrow for a few days of dirt biking and then a mountain biking trip through BC and Alberta for 2 weeks. Will avoid the Penticton area👍
There is a wildfire map for BC that you can check before you head out.
https://www2.gov.bc.ca/gov/content/safety/wildfire-status/wildfire-situation
@squamishdroc of course, if you travel through the north of the Okanagan, I've a beautiful new pair of speakers that you can stop in and audition
I'm by Swan Lake.
I will let you know if we pass through👍
The smoke sure rolled in today. This used to be a nice view of the hills.
https://photos.app.goo.gl/NPZBESqnUpRv3a2x7
I'm told Palmer Lake is burning down.
That looks like LA every morning
Sunny with clear skies today, snapped a quick pic while up on a roof looking at an ERV.
Realizing I hadn't updated this thread, I did complete a crossover update using VituixCAD instead of SoundEasy, and the improvements from this crossover update are not subtle. This speaker is now not only my most visually appealing, but also my most favourite to listen to.
The optimizations available with VituixCAD are all one should ever need, the crossover can be optimized by listening window, in-room response, power response, or the "listener preference rating" calculations that are based on Sean Olive's work, and fall in line with the preference score values found as AudioScienceReview. I found what works well is a 50/50% weight of listening window and in-room response, where the listening window target is -0.2dB/oct, and the in-room target is -0.8-1dB/oct depending on the speaker. Using this target, optimization to listener preference provides very little change in result.
Looking at the 6-pack of data, the only outlier is the on-axis peaking in the top end, which is left in place as a compensation for the directivity of the larger AMT. I'm sure most people looking at only the on-axis response would think that response is bonkers, and I certainly could provide an additional contour filter at 12kHz, but in listening I haven't felt the need to make further changes to the design, it sounds great as is, and I am comfortable knowing that the top end of the AMT is the only weak link. The balance of on-axis, in-room and power response creates a nice constant slope to the directivity index. The woofer data was hard to determine accurately with the woofer at floor level, so there may be inaccuracy to the simulated data there, but the result acoustically is perfect IMO.
Nice!
Honestly, the peak looks like what's exhibited by the BG neo's. Those sound just fine with it, too. Usually any mods to tame it make it sound worse.
Beautiful speakers, man!