New project 15" 3 way

[LonnyG]

Hello good people:
So i am working on another speaker project and have a few questions, I have mounted my drivers in a temp baffle to check sizes and crossovers, but at a certain freq and power level ( not extreme). I get a BRAAAAP out of the bass, these speakers are acoustic suspension Marsland 15" ,cloth surround treated with vintage Ar sealer, my question is how do these speakers react in an open baffle??? I hope it is not the speaker and will go away when I get them in a sealed box. Part two, the mids and tweets seem hot (not to the touch but loud) I have L-Pads coming for the tweets but how do I tame the mids??
Lonny

 

[turboyam]

The woofer is probably not suitable for open baffle, more for bass reflex or sealed... Post a picture of the rear of all the drivers, so we can see the magnet's size and the midrange back's. Is it closed back?, if not, it will need it's own chamber!.

 

[LonnyG]

I am planning on sealed boxes for this build , I was just testing the crossovers like this when it made the weird noise , I have two sets of mids, one open back one closed both the same manufacture,
As for tweeters I have phenolic ring or vifa d19s


Thanks for the input

 

[Scott75s1974]

Those look like great drivers!

Their cloth surrounds are very flexible because they are designed for acoustic suspension: the air pressure/vacuum of the sealed enclosure limits the movement of the voice coil, not the surround like on other drivers. If these are played w/o being in a sealed enclosure they will easily bottom out --probably the noise you describe. They should be fine when in a sealed enclosure. The danger of playing outside of that is that you might crack or deform the voice coil former. (see page 5 of the AR3 restoration guide)

 

[turnitdown]

Without T/S parameters, I'm not sure you'll even come up with the right enclosure - let alone blending all three drivers. Use the closed-back mids to avoid having to build "isolation" chambers into the cabinet.

 

[LonnyG]

Hello all,
I have been it touch with a guy who knows this woofer , just waiting to hear back, as for the mids the open back square magnet ones are new and the cones look great compared to the closed back ones, I might have to build an enclosure, Now the tweeters, the white phenolics are also Marsland Canada same as the woof and mids so I am trying to do an all Canadian build Marsland Solens and me . THe Vifa's will go in my KLH 23 Clones which
house the white Phenolics (unfortunately I only got 3 of them)The Marsland woofers had beautiful dark blue cones which are faded now and I can't see any way to bring them back..
Thanks guys/girls

 

[LonnyG]

Hey All , just waiting on building supplies and my l-pads to arrive . These will be done in red oak with cabernet + black stain (3:1 Cab to Black) I saw a a pair recently and loved the dark red/black figuring.
turnitdown I have done the math ( I hate homework) and have come up with a plan, I will run the crossovers externally to begin with incase I have to modify a bit.

 

[Lavane]

If you decide to bring those cones back to black, use a dye, not a spray paint or even that spray coating P.E. sells. You don't want to add weight to the cone.
Maybe Rits black dye and a very fine brush? Others may have ideas on what dye to use.

 

[LonnyG]

Thanks for the advice, but these cones were a brilliant blue color ,close to this.



as revealed when I replaced the dust caps, the fronts are faded bad the backs a little less but still faded . I don't dare try anything to restore the color for fear of damaging them.

Lonny

 

[Scott75s1974]

There are alcohol soluble aniline dies used in woodworking that might work without harming the cones. They come in blue. They are known for their poor colorfastness in UV light. So that could be what these had originally. But I understand your hesitance to mess with drivers for what is purely a visual issue.

It would be easy enough to test on a sacrificeable driver.

 

[LonnyG]

Thanks for all the suggestions about the dyes, I have been doing a little reading on dyes and do have said sacrificial drivers to test on.
I think this might work, " Rit® All Purpose Liquid Dye" it says it is safe for paper wood wicker etc. and it is not expensive .
I am just waiting for my carpenter to get back from a 10 day trip so I can get my boxes cut out. I am planning on a lot of trial and (no) errors
to get the cabernet stain just right, but I will be looking more into dyeing the cones for sure.

Lonny

 

[Scott75s1974]

this is one of the alcohol based dyes. Much less likely to mess with the paper cone: https://www.amazon.com/Blue-Dye-Sol...niline+dye+alcohol&qid=1634135797&sr=8-6&th=1

 

[JohnT123]

The black grain enhancement with the red stain on oak looks very hi-end. You're going to love it. I've seen other colours used for grain enhancement such as burgundy with a clear topcoat. Very cool and not an endangered species. Your lucky to have a guy that will do the woodwork. I have trouble getting shops to do stuff. They want a big minimum order so they can CNC everything. You really need a guy. Treat him well.

 

[LonnyG]

johnT , I agree that it should look good , I will have lots of short ends leftover to test stains and technique's on . I saw a pair of speakers (don't know the manufacture) but loved the dark dark dark red with the black graining
I've got an image in my head, now to get it out and on my wood. My "guy" is gone hunting/fishing for two weeks so I am in a holding pattern for now I will be updating regularly.
Lonny

 

[elvi]

You might query persons close to you with a speaker tester Parts Express sells.

It sweeps the drivers with a low power audio signal, then stores that in software.
You then add a small amount of mass, and sweep again.

The software displays the T S parameters, and that will guide you as to sealed or ported

 

[LonnyG]

elvi, I have already done that and have the box dimensions calculated, still waiting on my "saw guy" to get home, but I did get my cones dyed and they look great live not as blotchy as the pics. As to the glue spots that was the pervious owner that did the surrounds... three light applications of the aforementioned solvent based royal blue dye, thoroughly dried between coats, it really brought them back to a nice shade of blue and not anemic grey..

 

[baeron]

elvi, I have already done that and have the box dimensions calculated, still waiting on my "saw guy" to get home, but I did get my cones dyed and they look great live not as blotchy as the pics. As to the glue spots that was the pervious owner that did the surrounds...

View attachment 2372207

Looks great, good job!

 

[elvi]

Sealed?
Watching, and best of luck

 

[LonnyG]

elvi . yes they will be sealed boxes about 3.8 to 4.06 cubic feet internal. I did a pair of KLH Model 23 clones last year as my first foray into speaker making,
cloning or copying an existing model is easy, no math, did I mention I hate math and disliked woodworking until these covid-19 projects started to interest me.
Still waiting for my L-pads and my saw guy to get home, other than that I have everything ready to move forward.

My first two covid projects..

https://audiokarma.org/forums/index.php?threads/klh-model-23-dimensions.939140/
https://audiokarma.org/forums/index.php?threads/nos-jvc-l-fx4.948666/#post-14551600
Lonny

 

[g 22000]

Hi Lonny I have a pair of those 15" marslands also. I did not have any specs on them to build cabinets so I mounted them in a pair of 6 cubic foot enclosures I all ready had with a realistic super tweeter filling in the top end. I was impressed, very efficient and good bottom end, they have a lot of potential. I have been looking for something efficient to run with a low power tube amp like a single ended el84. Interested in any info you can share on them.
Al