Building the Nathan 10 - Page 2 - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 31st July 2008, 03:44 AM   #11
Luke G is offline Luke G  United States
diyAudio Member
 
Join Date: Apr 2007
That's some pretty gnarly looking router work there.

From the sound of it you would have been better off fully assembling them and then using a flush trim bit to line everything up. Then use a roundover for the edges.
  Reply With Quote
Old 31st July 2008, 08:05 AM   #12
Fosti is offline Fosti  Germany
diyAudio Member
 
Fosti's Avatar
 
Join Date: Jun 2006
Quote:
Originally posted by salas
Would you design a crossover with directivity characteristics comparable to the kit speakers, for your own box, woofer and CD?
Passive could take a while, but active......shure! I wouldn't go for passive anymore, it's an anachronism



Those are mine:
Attached Images
File Type: jpg 4420.jpg (57.1 KB, 3075 views)
__________________
"... they don't know what they do." - Thats right, quite often!
"... they don't do what they know." - That's right, even more often!!!
  Reply With Quote
Old 31st July 2008, 12:35 PM   #13
gedlee is offline gedlee  United States
diyAudio Member
 
Join Date: Dec 2004
Location: Novi, Michigan
The sides DO NOT mate with the front because the edge round is 1" and the MDF IS 3/4". Yes, all edges need a lot of sanding. The best way to do the edges is to assemble the entire cabinet and then route the edges, but in a kit you can't do that. So there is no way to get a nice clean routed edge. BUT, with a little putty and some sandpaper its no problem getting the edges right. A 1" router bit needs a 1/2" router and costs more than $100.

I had no touble assembling my cabinets with out any flaws. (I'll post pics of those here when I get them painted). But yes the parts are cut rough as they are cut by hand. And I did find that the 3/4" MDF was not actually .75, but more like .83" which made the cuts off a bit (this was not caught until after Markus kits were made).

If you are not competent at doing assembly work - filling, sanding, etc. then you should buy them assmbled.

As to the MDF not being very dense - well I question that comment as I have never seen any that is any different.

The foam used to pack the materials is the internal damping - I hope that you didn't throw it away.

The screws for the crossover terminals should have been in the kit.

The fit, will and has improved, but this is not a kit for a novice. You need to have experience at fitting and assembling an enclosure.

And I seriously hope that you are not going to roller on the Behr paint. Thats latex and will not give a very good look (although it will hide a lot of flaws). Spray cans are a far far better choice, but you need to do a good job of finishing the woodwork.
  Reply With Quote
Old 31st July 2008, 01:47 PM   #14
Banned
 
Join Date: May 2008
Location: Switzerland
Hi Earl,

the MDF in my kit is exactly 19 mm (0.75") thick.
I actually like to do assembly and finish by myself, but I would have returned pre cut parts when they vary like this. But that's not possible in this case because of the casted waveguide we're all eager to have in our hands.
You should also improve packaging as some boards got damaged. I'll post some pictures later.

Best, Markus
  Reply With Quote
Old 31st July 2008, 01:56 PM   #15
diyAudio Member
 
auplater's Avatar
 
Join Date: Apr 2005
Location: KyOhWVa tristate
Default Qc

It's always refreshing when a mfg. stands by their product and acknowledge that "the customer is always right", a well known (if somewhat dubious) reality of the business world.

it's also nice to see a response that doesn't patronize and/or chastise the customer for their perspective, especially on a DIY board.

Caveat Emptor I guess.


John L.
__________________
"...His brain is squirming like a toad..." Jim Morrison
  Reply With Quote
Old 31st July 2008, 02:15 PM   #16
gedlee is offline gedlee  United States
diyAudio Member
 
Join Date: Dec 2004
Location: Novi, Michigan
Default Assembled Nathan

The MDF thickness does vary, but on my samples its never as low as .75" and thats using a micrometer.

You got a kit with two enclosures in one box, right? I don't do that anymore because it was too heavy and would tend to get damaged. I use one box per speaker and these shouldn't be a problem as they are more reasonable to handle.

Those parts are not cut on a numerical machine, which is what everybody uses these days, they are all cut by hand and there is going to be some variation. To have them cut by machine would push the kit price up substantially. Is that what you want? The fact is that it is no problem assembling the enclosure to a fine fit if you are somewhat experienced with a sander and some filler as the photo below will show. And it hasn't even been finished sanded yet.

Click the image to open in full size.

If you are looking for precision to .5 mm then this is not a kit for you. If you are looking for the best sound quality obtainable for $1200 then you have it. You have to take the good with the bad.
  Reply With Quote
Old 31st July 2008, 02:33 PM   #17
pjpoes is offline pjpoes  United States
diyAudio Member
 
Join Date: Jan 2005
Location: New York
Send a message via AIM to pjpoes
Quote:
Originally posted by Fosti

Passive could take a while, but active......shure! I wouldn't go for passive anymore, it's an anachronism



Those are mine:

There is nothing anachronistic about a passive crossover. The concept and implementation is, at its essence, not much different from an active crossover. While there are certainly benefits to a multi-amped system using active crossovers, when it comes right down to it, you are still crossing over an electrical signal in essentially the same manner, through the use of LCR based filters. The biggest benefit to the active crossover is that it can use smaller cheaper parts, since they don't have to deal with the high currents, and thus be higher quality and better performing for a given price point. The negative is that they are far more complicated to implement correctly, and the average pro audio crossover does not have the necassary adjustments to properly integrate drivers (imo). Another big problem is that passive crossovers must use, if designed correctly, buffers, to ensure that the filters are fed a consistent signal. This means often noisy opamps and noisy power supplies to power the opamps. It doesn't have to mean this, but for whatever reason, a lot of even really high end crossovers are noisy in my opinion. Then you have digital crossovers, which while fully manipulatable, is a whole seperate back of tricks I have a current disdain for (again its noise issues). So for my point with all this, I don't see you being better able to implement a crossover for your setup on par with Dr. Geddes electronically short of using a highly manipulatable multipole (By this I mean one you can manipulate each pole and its q separately) active or digital active crossover.

As for Fit and Finish of these kits, I guess I was a little taken back when I saw, but I guess its not a huge deal. I purchased a kit once for my brother from a company in England who used precision CNC machined parts. While the MDF was cut pretty well, and everything looked like it was going to fit well, it didn't. Probably partly caused by the MDF swelling some, probably partly because precise cuts in a material like MDF isn't real easy. Anyway, because the enclosure was designed to fit together precisely, things actually came out worse than if it had been designed around looser tolerances. In the end, it required a lot of work to get everything working. It reminds me of the AK-47 vs American M16. While the M16 is clearly the superior engineering feat in weaponery, which precision tolerances, greater accuracy, and wider capability, it has been the AK-47's intentional inaccuracy that has made it such a versatile weapon that has stood the test of time.

Dr. Geddes, I just read what you wrote about the numerical cutting machines. I know of some companies I have used which can do decent precision mdf cutting on a numerical machine, and their prices have always been very decent. I would be surprised if it raised the price, and would think it would actually lower the price. Let me know if this is of any interest, and I can put you in contact with them. Also, if they can not handle your volume (They get backed up rather often), I know that GR Research has put me in contact with larger more professional companies, but I would worry that they would increase costs potentially unless enough volume was done.
  Reply With Quote
Old 31st July 2008, 02:41 PM   #18
gedlee is offline gedlee  United States
diyAudio Member
 
Join Date: Dec 2004
Location: Novi, Michigan
I should also point out that the assembled enclosure that I showed above used rejected parts that didn't even fit as well as what I shipped to Markus. Markus picture is not fair in that the enclosure is only loosley held together and the parts will shift.

As to passive versus active, I don't believe in active at all as there is absolutely no advantage, only a huge increase in cost. I have done both on numerous occasions and the passive always comes out just as well. In fact in one case we found that the active crossover parameters were way off and the settings could not be relied upon at all. It was a real pain. Give me passive every time.

To all, the parts in this kit are cut by hand NOT on a CNC machine. There will be variations. The waveguide ends up being pretty precise, but even then plastic shrinkage etc. makes the throat dimensions somewhat variable. But ALL of this is correctable and does not interfer with the final products performance in any way. Its just a little harder to assemble thats all.
  Reply With Quote
Old 31st July 2008, 03:06 PM   #19
diyAudio Member
 
Join Date: Jun 2004
Location: Green Bay, WI
Send a message via AIM to John_E_Janowitz Send a message via MSN to John_E_Janowitz Send a message via Yahoo to John_E_Janowitz
Quote:
Originally posted by gedlee
I should also point out that the assembled enclosure that I showed above used rejected parts that didn't even fit as well as what I shipped to Markus. Markus picture is not fair in that the enclosure is only loosley held together and the parts will shift.

As to passive versus active, I don't believe in active at all as there is absolutely no advantage, only a huge increase in cost. I have done both on numerous occasions and the passive always comes out just as well. In fact in one case we found that the active crossover parameters were way off and the settings could not be relied upon at all. It was a real pain. Give me passive every time.

To all, the parts in this kit are cut by hand NOT on a CNC machine. There will be variations. The waveguide ends up being pretty precise, but even then plastic shrinkage etc. makes the throat dimensions somewhat variable. But ALL of this is correctable and does not interfer with the final products performance in any way. Its just a little harder to assemble thats all.

If you're interested, send me an email. We have the CNC router here and can easily knock out something like this quickly. I've had a lot of experience making cabinets and knock down kits in the past. Simply making a jig to align all parts and clamp them together allows you to router all edges. As you temporarily align the cabinet you can even then draw pencil lines across the seams so people can use them to re-align everything together correctly. The ideal way would be to design the cabinet with miter joints so it pops together simply. You can do this whether you are using a CNC or not. Cutting miter joints on a table saw doesn't too take long either if you have a dado blade. Another option that works well for kits is to use pocket hole screws. The whole cabinet can then be screwed together and all the corners routered. Then simply take it apart and pack it up. They'd just have to fill in the pocket holes when done. Marglass or Glasslite works much better than standard body filler or wood filler. If you use a smaller roundover bit first when doing the edges, then go with the bigger 1" roundover will help eliminate the bouncing at the corners. Need to go nice and slow at the corners and hold the router tight, and also when cutting out the holes to avoid the bumps. Anyway, the offer is there if you are interested. We could cut these quickly and for not a lot of money.

John
  Reply With Quote
Old 31st July 2008, 03:27 PM   #20
gedlee is offline gedlee  United States
diyAudio Member
 
Join Date: Dec 2004
Location: Novi, Michigan
Quote:
Originally posted by John_E_Janowitz
and for not a lot of money.

John
John

Thanks, I already have quotes from people for this and the point is that with shipping etc. all this expense has to be added to the product cost since there is no room for it in the margins. Quite honestly, the fit has never been an issue for me and I don't understand why it is now. As I showed, the enclosure went together just fine for me and unless there are others who feel that they are willing to pay the extra cost for numerically cut parts, I am not inclined to increase the price to do so. They have and will get better with time as I work through the tolerancing issues.

I may go to an outside shop at some point because of workload, but probably not because of a better fit. At this point there needs to be a viable product at the lowest possible price, or there is no business at all.

E-mail me with a quote to do all the wood parts and I'll consider it, but from the quotes that I have seen, its not really worth the money at this point.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



New To Site? Need Help?

All times are GMT. The time now is 07:54 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2