New shelf box with AL170 and G25FFL (_WG)

[walwal]

There is no "instead", you can have both of it. Large chamfers around the tweeter, small ones around the woofer.

[Willy_65]

@walwal:
Your boxes are absolute jewels.
But my skils to build boxes are limited, I only have a solid Metabo sawing table and a "Lamellennutfräse" and "Oberfräse" from Ferm.
I should outsource the designs that you make to a carpenter, and they are very expensive.
My first set of boxes was the ALTO III C, I had the carpenter make an offer for the cabinet: it was more expensive than all the other parts together.

I always work with 1.8 cm MDF of high density, but you will understand that you can only make standard-looking speaker cabinets with it.
But that's ok for me, as long as the sound is good enough. Everyone was very satisfied with the boxes I already built.

I try to get the most out of my simulations with the limitations of what I can build in mind.

[Willy_65]

@jama
I now understand how to set "Baffle and position" for a more accurate simulation.
As with the Couplet, I use 1.8 cm left and right chamfers and I am very satisfied with the result.
6dB = 37Hz- @ 10dB = 32Hz-30kHz

[jama]

@ willy

https://heissmann-acoustics.de/en/wa...olautsprecher/

shelf = wall left & wall right

[Willy_65]

@ willy

https://heissmann-acoustics.de/en/wa...olautsprecher/

shelf = wall left & wall right

I'm not sure what you want to make clear with "shelf = wall left & wall right".

The Couplet has the same dimensions as my design and is described by Visaton as "a d'Appolito configuration shelf speaker". These speakers can be placed anywhere, including the ARIA 2 and many other 2-way systems.

My speakers must be placed on a piece of furniture about 2 m wide, on the left and right of a large TV and a tube amplifier with EL34 (2 x 30W RMS).
The listening distance is approximately 2.5 to 3 m from a large seating unit.
The room itself is approximately 5 x 4 m.

[Willy_65]

Thank you Jama and Walwal for the expert help.

I have ordered the PCBs, the finishing of the boxes themselves will have to wait a while, there are other activities in house (paints and wallpapering) that must now be given priority.

@walwal: did you make the front panel of those boxes yourself or by a carpenter, from solid wood? What was the thickness of the base panel?

@jama: which check boxes would you tick for the best simulation in the setup and space given below? Top + right and left or right and left only?

[walwal]

I made them by myself, thickness was 19 mm up to 60 mm (where necessary due chamfers) material was chipboard.

[Willy_65]

Several layers of MDF glued together and then made the final shape by sawing, filing, sanding and finishing with veneer. That must have been quite a job!

[jama]

or so

review the layout

[Willy_65]

Hi jama,

Indeed you are right, the R2 above L5 must be R5.

I had brought the value of that resistor from 2.7 to 2.2 because the top at 9kHz than is 85.5dB, just like the top value from low at 108Hz.
I know, it's just peanuts, at 2.7 ohms it's 85.25dB.

Is there perhaps another reason why you prefer 2.7?

[jama]

now ! 2,2 is ok ^^

[UweG]

I actually do not understand the target of this design. This high amount of parts for the crossover could be used to get a much smoother response. Is it not intended to get that result?

Seee attached file as an example. I also switched on the diffration at the top edge for the woofer.

[Willy_65]

My mouth falls open with surprise.
I will be happy to design and order new prints, which will cost me another € 18 (total for a minimum of 5 items), but that is negligible when I see this design.
- The frequency response is almost straight across the line, @10db = 33Hz-30kHz
- The phase transfer is perfect at the crossover point
- Frequency response direction to the top has been improved
- Impedance curve is almost straight and with an average of 5 ohms ideal for a tube amplifier at 4 ohms.

Thank you Uwe!
Thank you too, Jama, I was answering that I did like your last modification, but in the meantime the message came from Uwe, and ... that result is the best I can imagine.

[jama]

Why don’t you cable up like that example?

[Willy_65]

... impedance fine tuned to 5 ohms and 2x 22 ohms replaced by 1x 47 ohms.