Natalie p tweeter

[Jono_p33]

this may seem a very basic question, I am just about to finish my Natalie p build but was wondering about the wires to the tweeter. I have the backing plates in to isolate the tweeter from the pressure wave, but do I just drill a hole through them to pass the wires through and leave it open or am I meant to seal the wires where they come through so that its completely sealed off?

thanks

[JonMarsh]

Just drilling will work OK, but then you have a small air leak reducing the Q of the cabinet very slightly. It's better to use some silicone sealer or hot glue to seal the wire leads in the backing plate.

[Jono_p33]

Jon, thanks for the quick response. I just have to finish the veneer (matt black front with cedar veneer sides) but they sound amazing very detailed and clean. I am building these for my dad and he will be really only using these for music. Would you recommend them to be paired with a small sub just to get a bit more lower end since they are bookshelf speakers or do you think they are best without one.

Thanks again I think I will build another set next year for myself.

[JonMarsh]

A good sub never hurts- if you build the NatlieP in larger cabinets than the basic 1 cu ft design, you can get more extended bass from the 2 RS180's, but they're still just 7" woofers. A sub with variable crossover and phase controls would help optimize the blend between the sub and NatalieP's.

[Jono_p33]

Yeah I contemplated building the tower versions but he really likes bookshelf style for his setup.
Do you have any recommended DIY sub builds to pair or is it better just buying one?

[JonMarsh]

I'd have to go back and check what's been posted here and elsewhere- generally, it's fairly easy to do one- unless you like it to be really pretty- then that takes more work.

I'd look at PE and some of the knockdown PDF enclosures specifically designed for their UMAX woofers, then I'd look at some of the higher power sub plate amps (but not mount in in the box, probably- leave all the air space and the enclosure rigidity for the sub- ). It all depends on your budget. I'm doing a 15" UMAX for GF, with the specific PE MDF enclosure kit; I already have a Hypex Class D sub amp with EQ and controls. OTOH, buying a good commercial brand, if money isn't too much of an object, you can usually get something pretty nice- but I'd look for sealed designs, not ported- they'll probably be tighter sounding for music, though they won't play quite as loud. I recommended a KEF Q400, list is $699, to a colleague at work, and they were quite happy with it.

[Jono_p33]

Jon,

Thanks for your input with everything. I am going to order the UM10-22, 10" Ultimax and pair it with a BASH 300 I already have.

What are your thoughts on box size? in the description it say 0.585ft^3 according to bass box pro, I am still trying to learn how to properly use and interpret the software, but I see they also have a knock down kit of 0.75ft^3, would that be good? or I can build anything. I have access to a CNC machine that I already made the Natalie P's on.

[JonMarsh]

It's important to distinguish between what a design program initially kicks out, which often is just tuning for a B2 alignment (-3 dB down at Fb) and what is more usable for extension, which is usually a bit bigger with a lower Q and response -4 to -5 dB at a lower Fb. Given boundary reinforcement at low frequencies in typical rooms, that is usually more optimum. The PE knockdown kit is a good choice- I've build one of those, though for another driver!

[verderame]

Hi, in the coming months I will begin the construction of my natalie p, I would like to use quality capacitors but which is the most important elements in the crossover? Maybe 3UF or 24uf capacitor?
Thanks.

[JonMarsh]

The most important are those in series with the tweeter- C1 and C9. Because this is a two way, and because of the requirement for one of the LR3 zero's to be a bit far away from the nominal crossover frequency, C9 is a bit large. If you have the bucks, I'd recommend the Jantzen Superior Z caps. If you had money just coming out of your ears and didn't know what to do with it, go MR. But only if you have a really good front end, too. Remember that the 24 uF can be done by combining in parallel, you will likely have to for C1, also.

[verderame]

Thanks for the reply , it seems to be an upgrade rather expensive , I have to think about it . And what about L2 is so important to use 0,20ohm?

[JonMarsh]

I understand why you may be balking at the capacitor upgrade cost.

The NatalieP was developed as a reasonably high performance budget speaker- and original component choices reflect that. But the design performance overall has attracted folks to going for the full size tower cabinet instead of PE cab, and upgraded crossover components to realize the full potential. There are folks with the NatalieP's using $2K DAC's and other pretty nice middle range gear- I know of one NatalieP tower build that won the unlimited/open class competition at one DIY meet one year. They won't play as loud as something like a dual 8" or 10" woofer three way, but the fundamental quality of the design is pretty good- even some independent evaluations of the popular RS180 MTM's rate it highly.

What you spend should be consonant with the rest of your system, in principle, though if you plan on keeping these for some years and upgrading in the future, you might want to start off with the good stuff in the crossover. These are just the same kind of components used in projects like the Ardent/Wavecor Ardent and Isiris- they're parts I'm very familiar with.

http://www.rjbaudio.com/RS180MTM/rs180-rs28-mtm.html

The DCR component in series with the woofer controls the insertion loss. If you use a high DCR inductor, this lowered the mid woofer output level and decreases the low frequency damping because of the extra resistance in series. The original design specifies a large air coil inductor, with AWG14 wire. You could even go to AWG12, or go to a high performance cored inductor, such as the types used in the Wavecor Ardent. (Erse SuperQ). They don't have as fine a granularity in values as air core types do, so you'd have to get a 1.5mH and unwind it, checking with an LCR meter, to get the right inductance. I've done this a number of times. Going that route you could wind up with a DCR of 0.1 ohms. Easier just to stick with the original part, of course, or something similar like the 1.2 mH Erse AWG14, with DCR rated at 0.24. (that is actually more expensive than the modified 1.5mH Erse SuperQ, but I realize a lot of folks don't have LCR meters sitting around in every room, or any room! )

[---k---]

Natalie MTM design

Please forgive me for not remembering who designed the Natalie version for these drivers but I would have to say that it is one of the most interesting crossover designs I've seen and it has a very nice looking response. The crossover is a sort of mutated series crossover that is like nothing I've ever seen before but the response looks great and the parts count isn't too bad. The details are shown below.

I always loved his description of your crossover.

[JonMarsh]

I always loved his description of your crossover.

Me, too! :W :B

[verderame]

Thanks Jon , your explanations are always very clear and complete.
As you say before is important to know ther rest of the system .
Currently for the 2 channels listening I use two full statements ( i love my statements...) I recently changed the caps on the tweeter with the Jantzen Superior z and the mid inductor coil with the Jantzen wax and the result was amazing ! After I reconnect them I could only say wow ! I could not believe what I was hearing , the separation of the instruments, the position in space , the clarity of the voices , everything changed significantly in better !
That happened with my clone rogers after replacing the cap too ...so I belive in a good caps! :-D
Returning to natalie p , I will used them for the home theather system , so multichannel listening for the ' 80/90 % , amplifier is yamaha rx - v671 , nothing particularly expensive.
I thought of two solutions, build speakers with basic components and then think about a possible upgrade in the future , or use mid level capacitors like the Mundorf evo for C1 and C9 and have a happy life ....:-DD

[mischmat]

Quick question. I'm slowly getting back to my natp project and had the same question bouncing around in my head as verderame. I was going to order Dayton 1% from Solen since they now carry Dayton however there's only 4 left in stock for the c1/c9 in the 12uf. My option is to either order 2 of the 5% or change brands to Solen. I was thinking the 630v but am wondering if it would be comparable to the 1%.