3-way - Tower Speaker Project with Seas Drivers

[Inductor]

I am using the PMS xover, with modified resister values that I will experiment with....

Problem is, on his website the list of components includes 4 capacitors that are not shown on his schemetic. So i dont realy know what to order atm.

I really would be gratefull if someone could shed some light on this for me. Here is the direct link to the xover diagram, with the un matching list of capacitors....
http://www.troelsgravesen.dk/PMS.htm...05 crossover

I can see you have a problem but it will take me one day or two to read the Troels webpost ((and this thread if needed)). Unless somebody following your project knows the answer already...

 

[WaVeInFoRm]

Just a small update. I have cut all of the ply panels today. each one is cut between a 1cm-4cm larger than the face they will be on. This was to allow for tear off, from the ply when cutting with a hand saw.

Before I fix the ply faces into place and cut them flush, I need to spend some time experementing the best method to avoid the ply splintering.

The order is. top and bottom of boxes. side of boxes. back and front of boxes. This means the ply edgeing will be visable on the top and sides. but I dont really mind, as I dont see any way to miter each face with my tools

I will post more pics further through the build process.

I thought I should mention. my midrange cabinet ended up as 10.02 liters - mid and tweeter magnets.. Is this ok?

I also need to finish my "lonley" brace.. as the walls are going to total 31mm thick this should be ample

 

[DrDyna]

The site says the list includes extra parts for different versions. If ordered as a kit from Jantzen, he says the extra parts are included for free. If you're purchasing the parts from somewhere else, you'll probably have to figure out which ones you don't need.

 

[Inductor]

I thought I should mention. my midrange cabinet ended up as 10.02 liters - mid and tweeter magnets.. Is this ok?

Yes, that's a problem. Not the same tunning consequently the xover would change. I can say from simulation that it doesn't work. I can see that Troels is using an adequate box (VB) 4.3 L with a kind of high tunning port FB = 80/82 Hz (some damping). Use same exact size and tunning/port. ex:
VB = 4.3 L, FB = 80/82 Hz (81.75); f3 ~ 85 Hz
VB = 4.5 L, FB = 81.0 Hz; f3 ~ 84 Hz

ps: I understand that at this range ~100Hz is not going to affect very much (at the woofer output, xover high attenuation for mid ~25dB) but besides experimenting different alignments in the mid like a sealed box, a double volume enclosure with a (BR) might give you a unexpected fanny sound output.
A sealed box with a different response curve would also most probably need a different xover. (f3 ~ 150 Hz with a high QTC/~0.6, VB = 3.0 L)

 

[Inductor]

Drivers:
Woofer H1288-08 CA22RNX - Seas
Mid H1262-08 MCA15RCY - Seas
Tweeter H0881-06 27TFFC - Seas
Crossover (as the last version from Troels' PMS)
LF:
L3011 - 4.7 mH
C3021 - 48 uF
MF:
R2011 - 1R0
C2021 - 43 uF
R2031 - 2R2
L2031 - 4.7 mH
L2041 - 0.82 mH
R2061 - 1R5
C2061 - 10 uF
HF:
R1011 - 3R3
C1021 - 10 uF
L1031 - 0.1 mH
C1041 - 15 uF
(note different hf components for differ. tweeter version).

 

[WaVeInFoRm]

Yes, that's a problem. Not the same tunning consequently the xover would change. I can say from simulation that it doesn't work. I can see that Troels is using an adequate box (VB) 4.3 L with a kind of high tunning port FB = 80/82 Hz (some damping). Use same exact size and tunning/port. ex:
VB = 4.3 L, FB = 80/82 Hz (81.75); f3 ~ 85 Hz
VB = 4.5 L, FB = 81.0 Hz; f3 ~ 84 Hz

ps: I understand that at this range ~100Hz is not going to affect very much (at the woofer output, xover high attenuation for mid ~25dB) but besides experimenting different alignments in the mid like a sealed box, a double volume enclosure with a (BR) might give you a unexpected fanny sound output.
A sealed box with a different response curve would also most probably need a different xover. (f3 ~ 150 Hz with a high QTC/~0.6, VB = 3.0 L)

Thats interesting,

10.02liters minus volume of driver magnets/cone so probubly at a guess around 9.5liters

I thought I should mention, as you mentioned tuning frequency. It is a sealed cabinet. (atm)

My logic here, was to have plenty of space to absorb the backwave better than a smaller cabinet. Was planning to just line the walls with 1cm foam carpet underlay stuff, and some lose fiberglass filling

But if I am wrong? I "could" adapt the volume of the box ,with a deviding panel .. and then add a small port at the rear...

 

[WaVeInFoRm]

The site says the list includes extra parts for different versions. If ordered as a kit from Jantzen, he says the extra parts are included for free. If you're purchasing the parts from somewhere else, you'll probably have to figure out which ones you don't need.

Ah i see!, It all makes sence now. those extra caps where for the scanspeak tweeter version.
Im happy thats solved then

 

[Inductor]

RELATING TO POST #106
I would do that if the sealed box to big use a thicker liner/sound absorbent (30mm layers) or stuff more the interior space. The lower output of the mid driver should integrate well, if not you can listen when the set/speakers/room is all complete and working... in real auditions.
Cabinet-damping

 

[WaVeInFoRm]

RELATING TO POST #106
I would do that if the sealed box to big use a thicker liner/sound absorbent (30mm layers) or stuff more the interior space. The lower output of the mid driver should integrate well, if not you can listen when the set/speakers/room is all complete and working... in real auditions.
Cabinet-damping

I got a roll of this stuff from B&Q. Knauf EkoRoll Loft Insulation 100mm, 5012061862249
The plan being to staple a layer of it to line all the cabinet walls of the woofer cabinet, as it copresses fairly well.

Looked like it would be good, is it?

If not i could return it and buy some skin freindly plastic stuff
homeECO Recycled Plastic Insulation 370mm x 4m 200mm, 0000004008668

Not sure how well it would work for sound dampening.
I am assuming different materials work better for different frequency ranges...




For the mid boxes, this would be in the way of the driver, so i was going to line the boxes, then fill it up with some spare speaker wool I found from some old speakers

 

[WaVeInFoRm]

Infact I think i have had enougth of "bad for me" materials, do you think the plasticy stuff will work just as well? I can easly get a refund on the fibreglass stuff...
homeECO Recycled Plastic Insulation 370mm x 4m 200mm, 0000004008668
Polyester is basicly plastic anyway... and troels seems to approve of it as a dampening material... In the above posted guide

http://australian-government-insulation-rebates.com/Products/polyester-insulation.html

However this is not entirely polyester, I found this.....
"A roll of white recycled plastic loft insulation contained within a blue and clear plastic bag, the insulation is made from 90% recycled plastic bottles with 10% polyester bonding to create a totally itch-free material."

Any thoughts?

 

[DrDyna]

Infact I think i have had enougth of "bad for me" materials, do you think the plasticy stuff will work just as well? I can easly get a refund on the fibreglass stuff...
homeECO Recycled Plastic Insulation 370mm x 4m 200mm, 0000004008668
Polyester is basicly plastic anyway... and troels seems to approve of it as a dampening material... In the above posted guide

Polyester Insulation - Buy, Supply, Install Polyester Insulation

However this is not entirely polyester, I found this.....
"A roll of white recycled plastic loft insulation contained within a blue and clear plastic bag, the insulation is made from 90% recycled plastic bottles with 10% polyester bonding to create a totally itch-free material."

Any thoughts?

I'm not sure that material would have the same sonic characteristics as rockwool or polyfill. It sounds like it could become reflective at some frequencies if it's made of shredded plastic.

 

[Inductor]

I think you should be looking more (google for your local area) under sound absorption and soundproofing products not insulation. Some of this are also of good use like rock-wool used in the construction industry. If you understand the concept (different in the case of BR and sealed) it will be easier.
Now to be practical and only as an example of many, adapt to your case
1. A layer against the walls of a thick material like "acoustic grade rock mineral wool slab"
Acoustic Rock Wool
or Vicoustic Vifoam 40mm/Vicycle (both alternatives to mineral wool)
www.vicoustic.com
I personally like to use the Vicoustic Vicycle type
2. A material like bats of (real/organic and the most effective) wool as filling material and sound absorbent, also the same as the "30 mm polyester damping sheets" (you can buy everywhere).
http://jantzen-audio.com/image/accessoreis/Jantzen_Audio_Denmark_-_Damping_materials[1].pdf

 

[WaVeInFoRm]

I went and hurt my back. Not from lifting heavy speakers.. But from setting up a gazibo of all things!
So no physical progress.

I am ordering my xover parts.
They have jantzen, cross caps, and jantzen standard cross caps.
The standard blue ones, are rougthly twice the price of the black jatzen cross caps.

As far as I can ascertain, there really is no differance between the two, but i may be wrong, so any advice is appreciated.

Now to add to the confusion,

For example, where there are 33uf and 10uf cap in parallel.. Is there any reason a superior z cap 10uf with a standard or a black cross cap 33uf, is worthwile, or will the "lower quality one" in the paralel circit balance out the "higher quality one


Excluding the silver and gold caps from the jatzen range,

The only mentioned, differance between the superior caps and the standard is the copper lead wire

And I cannot figure out any differance between the standard z cap, and the jatzen cross caps

I would feel like a sucker, if I paid twice as much for the same thing....
http://www.europe-audio.com/Product.asp?Product_ID=8501
http://www.europe-audio.com/Product.asp?Product_ID=8962
So I really need to be sure there is a differance.......

They all seem to be metallized polypropylene, And before I concider spending extra on the more expensive caps, I really need to now the sweet spot in the market, or have this cleaned up. I dont want to be paying extra for a fancy looking version of the same thing.

So la la placebo effect of gold wires and junk aside, where is the point between normal, and stupidly expencice, where performance is at its almost optimum, the point where the extra £100 gains you 2%, that kind of place

Right now Im fancying the black cross caps, and if the blue standard caps are better, Im happy to pay more

Thanks

Just checking....

Any views or opinions on this are welcome
http://www.europe-audio.com/document.asp?document_id=3197&link=datasheets\jantzen\Cross_Cap_C.pdf
http://www.europe-audio.com/document.asp?document_id=2778&link=datasheets\jantzen\Z-cap-Standard.pdf
http://www.europe-audio.com/document.asp?document_id=2764&link=datasheets\jantzen\Z-cap-Superior.pdf

 

[DrDyna]

This might help:

super-caps

 

[WaVeInFoRm]

This might help:

super-caps

Thanks, I have had a read, are all jatzen caps in the "supercap" category?
but it still doesnt answer what the atual diffrances are between, jatzen black cross caps, and jatzen blue standard cross caps. The latter being twice the price.

As far as I am aware both caps are made from the same material. and as they are both the same size, and identical exept color, I reason that they are both internally the same or simular, but I may be wrong, I guess I need to find out what the differance atually is before spending twice the money!

 

[DrDyna]

Thanks, I have had a read, are all jatzen caps in the "supercap" category?
but it still doesnt answer what the atual diffrances are between, jatzen black cross caps, and jatzen blue standard cross caps. The latter being twice the price.

As far as I am aware both caps are made from the same material. and as they are both the same size, and identical exept color, I reason that they are both internally the same or simular, but I may be wrong, I guess I need to find out what the differance atually is before spending twice the money!

You might be able to e-mail them and ask, I'm sure they have a response ready for that question

 

[WaVeInFoRm]

Im awaiting there responce, with great anticipation

I was, assuming; some one here knew more about there pysical make up.

But emailing them was a good idea! hopefully they will provide my answer

 

[WaVeInFoRm]

Well. looks like there not intending to reply.

I asked them what the differance between the black cross caps and the standard blue caps. and no reply.

Maybe there isnt a differance
Im not paying twice as much if i dont know what im paying for.. thats nonsensical

I shall be using the black cross caps http://www.europe-audio.com/Product.asp?Product_ID=8962

as they are probably decent enougth caps anyway
http://www.europe-audio.com/Product.asp?Product_ID=8962

 

[Inductor]

black vs. blue
The Jantzen Audio Standard Z-Cap (blue) is classified with 6.5 by the ""Capacitor Test @ Humble Homemade Hifi – 04.2012""
The tolerances are tighter (blue) 3% vs. 5% (black) (read datasheets).

Tolerance: max. 5%, typically 3%

They are/look similar, from the test mentioned, real difference can be achieved with the more advanced Jantzen Audio Superior Z-Cap *10 (*also a personal favorite).
This 10 points mean also a 10th place in 69 caps tested, head to head with caps like the #9. Mundorf M-Cap Supreme Silver/Oil *10.5 and the #11 Obbligato Aluminium Foil * also with 10 points in a maximum of 14.

 

[Inductor]

Of course you can use the more expensive ones (caps) in line with the tweeter or in a later upgrade.