My Natalie P Journey Begins

[wkhanna]

I've been experimenting with finishes.
I bought some TransTint Bordeaux at Woodcraft.
I got this on one of my test pieces using the transtint mixed with alcohol as a tint applied directly to the Baltic birch and two coats of tung oil over top.

[yousuredo2]

that is red...almost metalic looking
reminds me of a guitar finish...
Looks cool.

~~~EDIT~~~
if at all posible, make a template of the side peices for the stands...

[wkhanna]

if at all posible, make a template of the side peices for the stands...

Yep, Already done.

Originally, I had planned on using TransTint Red, described on their site as ‘fire engine red’.
The overall design has Scandinavian style, and in a room with modern decor, I felt they would blend well in that shade. However, my current music room is also our living room, and is quite eclectic, decor-wise. A bright shade of red would probably tend to be overpowering in the long-term.

I took my wife over to the Woodcraft store, and had her look at some sample chips they had on display. We both decided the Bordeaux was a good compromise while still maintaining a slightly more dramatic and different look.

[wkhanna]

Question......

Does placing a horizontal brace at the centerline of the drivers, have any effect, either good or bad, on internal wave reactions?

[ThomasW]

Just make sure the bracing doesn't obstruct any vents in the back of the drivers.

[BigJim_inFLA]

Question......

Does placing a horizontal brace at the centerline of the drivers, have any effect, either good or bad, on internal wave reactions?

Those braces are 1.25" off the center of the driver and have 1.5" clearance from the back of the magnet. :T

Yours are coming along nicely! That red looks good on the baltic birch.

Mine should be finished tomorrow, can't wait!

Jim

[wkhanna]

Good work there Bill.
I love the pic of the wine glass, followed by the shot of the wine glass and the Marlboro pack.
Next shot should be the speaker, Marlboro pack, glass of wine and of course some cheese. :rofl:
Looks like you have something good going on.

Mike

This one is just for you, Mike!

[wkhanna]

Those braces are 1.25" off the center of the driver and have 1.5" clearance from the back of the magnet. :T



Jim

Thanks for details, Jim. I liked your design, and they say plagiarizing is the greatest form of flattery, so I went with something very similar.

Mine should be finished tomorrow, can't wait!Jim

Green with envy!

Question for you Jim.....
How long did you wait before you put to put the shellac over the linseed oil?

[BigJim_inFLA]

Question for you Jim.....
How long did you wait before you put to put the shellac over the linseed oil?

About 12 hours.

[wkhanna]

Can someone give me a hand?

I’ve been pulling my hair out ( which is rapidly becoming a resource in short supply as I turned 49 this past weekend) over the port length for my ‘Twins’.
After accounting for xo, drivers and braces, I have ended up with an internal volume just under 67 litres, not counting the volume of the 3" Precision Port.

The calculator at the PP website says 7.75" for 30 Hz, 6.7.5" for 32 Hz and 5.8" for 34 Hz using the three inch flared ports I have. The curves seem to look OK in WinISD, (remember, I'm still a NooB), with the lower tuning showing a smoother roll-off.

I ended up a few litres over of the 60 mark that our Dark Master recommended. Should I be concerned, and add some ‘dead space’ to bring the volume down to near 60 litre, or can I rely on the curves I get in WinISD and not worry about decreased resistance a shorter port will put on the drivers?

[kingpin]

This one is just for you, Mike!

MMMMMMMM Cheese. :B
Can't wait to see those boys done Bill.
I am sure you will be as happy with your Nat P's as I am with my speakers.

Mike

[Finleyville]

Those are looking great so far! I cannot wait to see the finished project!

[wkhanna]

I got to point where I could test my XO’s today.
I ran the wires out the port of one cabinet and hooked up the XO outside, you can see it on the floor.
I just was curious if everything was going to work.

I had my old speaker connected to other channel, and did an informal A/B at very, very low level using Steely Dan’s ‘Aja.’ All seemed well, so I hooked up my second ‘twin’.

My wife had been listening to Queen, ‘Greatest Hits I, II and III’, earlier in the day with my old speakers while I was working in the garage on the 'Twins', so I had her come in and tell me if she could hear a difference when playing the same tracks she had just heard.
She seemed QUITE PLEASED.

XO’s seem to be working OK. At least up to what I estimate was around 98 db.

Evaluation continued with Steely Dan ‘Royal Scam’, followed by some Citizen Cope, Santana ‘Abraxas’ and culminating with Miles Davis, ‘Some Day My Prince Will Come’.

I made a mistake. I may never take the time to finish the ‘Twins’. I’m too enthralled with all the new sounds coming from my new babies.

If I ever can pull myself away from my listening chair, I will follow up with more details, but don’t hold your breath, the Dark Side of the Force has permeated to my very core like a feather caught in a black hole. My Dark Lord, your bidding is my only concern.
And to Sir John, no words could express my gratitude.

[wkhanna]

I Just dropped in Miles Davis ‘Kind of Blue’ in my Cdp.
Track #3 ‘Blue in Green’; I can hear every single bristle of Jimmy Cobb’s brushes on his snare.
And I can tell when it’s in the center or on the edge of the drum.

I may be late for work tomorrow.

[dlneubec]

I Just dropped in Miles Davis ‘Kind of Blue’ in my Cdp.
Track #3 ‘Blue in Green’; I can hear every single bristle of Jimmy Cobb’s brushes on his snare.
And I can tell when it’s in the center or on the edge of the drum.

I may be late for work tomorrow.

Nice Job! I like the angled top. It makes them look different than the typical box. Wait until you hear them in a few weeks when the drivers are really broken in. :T

FYI, I used to use those threaded insert nuts, but have changed over to hurricane nuts, which I have found to be much easier to get in straight. YMMV.

[JonMarsh]

Can someone give me a hand?

I’ve been pulling my hair out ( which is rapidly becoming a resource in short supply as I turned 49 this past weekend) over the port length for my ‘Twins’.
After accounting for xo, drivers and braces, I have ended up with an internal volume just under 67 litres, not counting the volume of the 3" Precision Port.

The calculator at the PP website says 7.75" for 30 Hz, 6.7.5" for 32 Hz and 5.8" for 34 Hz using the three inch flared ports I have. The curves seem to look OK in WinISD, (remember, I'm still a NooB), with the lower tuning showing a smoother roll-off.

I ended up a few litres over of the 60 mark that our Dark Master recommended. Should I be concerned, and add some ‘dead space’ to bring the volume down to near 60 litre, or can I rely on the curves I get in WinISD and not worry about decreased resistance a shorter port will put on the drivers?

Per centage wise, that amounts to a small change in the tuning; I wouldn't agonize over it; the larger volume gives you a slightly lower tuning, which should be no problem, as there's still substantial port output going up for one octave. If you have Office on your PC, I recommend using Unibox over WINISD. It will give you more info, and IMO has more reliable results.

~Jon

[BigJim_inFLA]

I made a mistake. I may never take the time to finish the ‘Twins’. I’m too enthralled with all the new sounds coming from my new babies.

Now you have to build another project. When you hook those up you can finish these, then build another...and another...

[wkhanna]

Thank you, Jon!

A couple more pics:

[dlneubec]

Thank you, Jon!

A couple more pics:

How are you going to treat the edges of the solid wood baffle (roundover, chamfer, etc.) and connect it to the box? I assume you have an mdf baffle behind the solid wood one.

I would have run the grain of the veneer on the body vertically, but that's just me. :W

[wkhanna]

How are you going to treat the edges of the solid wood baffle (roundover, chamfer, etc.) and connect it to the box?

I have been following JonW's thread and see the my original idea of going with a 3/4" round-over may be improved by going with a 45 deg chamfer with blending of the sharp edges. My feel for now is, the blended chamfer will complement the look of my cabinets, so I may give that a try.
I plan on glueing the baffles.

I assume you have an mdf baffle behind the solid wood one.

Inner baffle is 3/4" BB ply and outer baffle is 3/4" poplar.

I would have run the grain of the veneer on the body vertically, but that's just me.

To quote your earlier post; "I like the angled top. It makes them look different than the typical box."

Also, the cabinets are angled 5 deg back from top to bottom.

I still have to do some calculations and will be making some FR measurements using a RS db meter to finalize the port length, but all I can say at this point is “Got Bass!”

[wkhanna]

Now you have to build another project. When you hook those up you can finish these, then build another...and another...

Can you say 'Dipole'!!!

[wkhanna]

For my bases, I used two 3/4" pieces of MDF, laminated together.
I put a counter bore in for the T-nuts. Then pressed them in with a C-clamp.

I now know what you guys mean about MDF dust, this was the first time I did any real cutting with this stuff. I may be last, too. It chips on the corners so easy, the dust so fine it gets everywhere, and I can tell it is really hard on the tool edges. I will only work with stuff outside, if I ever use it again.

[wkhanna]

Well, My wife and I are still trying to decide if we like the bases or not.

It seems no matter how many ways you model something on CAD, it always looks different in reality. I’m not quite sure, maybe the proportions are wrong, or it just does not integrate into the cabinet design. Maybe I just need to give it a while, and see if it grows on us.

I need feedback, guys. Give me your input Yea, or Nay?

[Jed]

In this case I'd say less is more. Go with something minimal in design, yet functional.

[kingpin]

Well, My wife and I are still trying to decide if we like the bases or not.

It seems no matter how many ways you model something on CAD, it always looks different in reality. I’m not quite sure, maybe the proportions are wrong, or it just does not integrate into the cabinet design. Maybe I just need to give it a while, and see if it grows on us.

I need feedback, guys. Give me your input Yea, or Nay?

I think you have to lower the height between the bottom of the speaker and the top of the base. Maybe 25-50% height reduction.

Also double up the thickness of the base and the legs. Their mass may not be matching up to the mass of the Nat P's.

But to me, bigger is always better. :B

Also it may look a bit off right now because you don't habe the roundover on the baffle done, which will look better with the rounding design in the feet.
Right now you are looking at square edges on the speakers and round edges on the feet. Doesn't match up right. :T

Mike

[ThomasW]

I need feedback, guys. Give me your input Yea, or Nay?

The height and mass of the vertical risers seem out of proportion with the cabinet and base.

This is what we used for Tibor's mini-towers

[BigJim_inFLA]

I think you have to lower the height between the bottom of the speaker and the top of the base. Maybe 25-50% height reduction.

Don't think he can, those are bottom ported, that's why he needs them up on the stands in the first place.

[cjd]

With the amount of space between I think the bases are too large as far as width (possibly depth). To integrate you need them to flow into the main lines of the speaker, and they fail to do that because they're wider. You might be able to get creative with some surface treatment on the main speakers that carries through to the base corners, but that's only a maybe. I think they'll still seem awkward.

C

[speedle]

I guess I'd have to agree. It's the "massing" from an architectural point of view and maybe a little more of that is what you need. I think I get the kind of look you're going for, with the slanted top, and horizontal grain on the sides, etc. Kinda reminds me of some of the higher end Usher models. Which I like, onacuz that's exactly the look I wanted to put on my Natalies! :T

[dCraig]

My two cents is that it is the thickness of the legs on the base piece that is where mass is needed. If the legs were two inchies thick then the whole base then begins to look more massive without compromising your deisgn.

By the way, did you eever see the movie "Chicke Little"? With the slanted top, these remind me of the little baby alien that got lost. He was cute, and so are the speakers. They look FAST!

I know they will sound great.

[wkhanna]

My thanks to all of you for your brutal...... err, I mean honest opinions.
I had exactly the same thoughts as you guys.

So, yesterday morning, I took the stands down to the garage for some ‘cosmetic surgery’.
After removing 4" from the length, 3" from the width and putting a 45 deg chamfer on the struts, I am going to move on for now, and finish everything else first. I may come back and do a redesign if, after the cabinets are stained and finished, they still don’t seem to work visually.

I did finish the baffles, 45 deg chamfer with mild rounding with my orbital sander. It’s as though they went to boot camp. They look so much slimmer and taller, much more pleasing visually.

Thanks again for putting up with my obsessive bantering, I just needed some moral support as I near the stages of finality of this journey and start second guessing myself.

[wkhanna]

They look FAST!

I know they will sound great.

Thanks, that is exactly what I was going for, a sense of movement or motion; as opposed to a static monolith look. (my wife said I should put a rear spoiler on them!?!?!)

And they already sound far better than I had ever dreamed, I have been experimenting with foam placement and port tuning. These changes have had minimal effects, but the baseline of the sound is just stunning.

[wkhanna]

Some teasers for you, I only have one coat of tung oil on so far.
Still working on a stand/feet design, though.

[joecarrow]

They're looking GREAT! I love the deep red color- I'm sure they look even better in person.

[BigJim_inFLA]

Beautiful finish! :T

[kingpin]

Definetly a sharp looking speaker. 8)
Great work. :T

Where is the wine and cheese. :B

[Evil Twin]

Very handsome work- the Force is strong in this one...

[speedle]

What a sweet shade of red!

[wkhanna]

Thanks to you all for your kind comments!

I now have five coats of tung oil rubbed in, and will most likely be putting some shellac over top.

And to you, my Dark Lord, your approval is my only goal, and your humble and obedient servant is ready for his next assignment.

I did a fq plot using a test tone CD that PewterTA made for me, it is in one Hz increments from 20Hz up. I used a RS digital meter positioned at my listening location, about 11 feet from the 'Twins'. There is no correction factors for the points I plotted. Feed back please!

Do I need to use correction factors with the digital meter? I can only find the ones for the analog meter. I am still trying to finalize my port length. My measurements are including 'room effect', which I thought I would want since I am concerned with how they sound while I am listening, or should I be taking measurements closer to the speaker to help minimize room reflection?


Edit: do you think there is some kind of wave cancellation going on inside my cabinets?
I have minimal damping material on the rear panel and top only. Could this be due to the inherent fq of my boxes?

BTW: measurements where taken with settings at 'C' weighting on 'Slow' response. Each tone was run for ~ 10 sec.

[PewterTA]

Yep I heard them and in my opinion, they sound really good! I am definitely impressed for a DIY speaker (especially with this being Bill's first). He's done a HECK of a job with them. I have to tell you the pictures do not do the speakers justice...they look so much better IRL.

I would say that they definitely compare to my B&W 604 S3s that I have with slightly less bass extension (due to the 604s having dual bass drivers). The only other real difference that I noticed is that I think my B&Ws have a slighly clearer sound and slightly different imaging...which this could be due to the differences in amps and drivers. I only could tell after I got back home and re-listened to the same things we had listen to on "the twins." Otherwise, I would've said they are identical. The sound difference also could be related to the B&Ws having a "brighter" sound to them as well. I will definitely say at the levels we were listening to (~80 - 95db) there was no listening fatigue at all ... which Bill's old speakers did give you some fatigue.

But all in all, completely 110% impressed. And knowing that they ("The Twins") will only get better with each tweak that Bill does...wooooo hoooo!!!

Looking at the plotting, you definitely should factor in the correction factors for the RS meter. Digital and Analog all should be close in their readings and until you get an actual microphone, it's good enough.

Once you get a good microphone to do a reall good freq. response test, you will need to move the speaker outside so you don't get any room reflections. Right now that "null" you have between 35 - 52hz could be a lot to do with the room... (not saying that's the only issue)...but could be a good deal.

Another thing you are also probably doing is measuring both speakers at the same time, which you need to measure one at a time and I bet each speaker will respond differently (even though they are set up identical)...this is due to your room acoustics.

[ThomasW]

Edit: do you think there is some kind of wave cancellation going on inside my cabinets?
I have minimal damping material on the rear panel and top only. Could this be due to the inherent fq of my boxes?

That's room interaction not the drivers. If you want to see want the woofers are doing, run a plot with the SPL meter 1" from the center of the cone of one of the woofers. If they're ported (sorry I don't remember) run another plot at the outlet of the port.

These combined will tell you roughly what the speaker is doing independent of the room.

[wkhanna]

Well, After mounting the xo’s, finding out I put WAY TOO much tung oil on, and having to actually sand it down, I now have 4 coats of varnish (cut 50/50 with mineral spirits) that will get rubbed out next week after it drys throughly.

I also just finish my 4th iteration of speaker stands. I think I am finally happy with this one.

Any thoughts on a color for them?

[Dan B]

Well, After mounting the xo’s, finding out I put WAY TOO much tung oil on, and having to actually sand it down, I now have 4 coats of varnish (cut 50/50 with mineral spirits) that will get rubbed out next week after it drys throughly.

I also just finish my 4th iteration of speaker stands. I think I am finally happy with this one.

Any thoughts on a color for them?

BLACK!

[speedle]

Yes, black. Satin, gloss, it's hard to say, but black would really rock!

[nayr]

I'm going to go against the crowd and say Rega P3 green