JGs Mini Monitor - additional questions

[Benny the 2.]

Hi.

As I searched this board, I found some threads which said, that James Griffin once posted (or handed out) a parts list of his Mini Monitor...
Well, I have the PDF from Creativesound laying by my side, but there are still two questions, which could not be answered yet.

1.
If I'm going to build the ported version instead of the sealed, what length do the ports have?
Sorry, but I didn't find any answer...

2.
Is it correct, that the two coils, which wire diameters are given in AWG are 1,3 mm (16 AWG) and 0,8 mm (20 AWG)?
A friend told me so, but I want to prove his answers instead of making any mistakes...

Could anyone drop me an email containing that parts list, or tell me where to get it from, please.

Thanks for replying.

B.

[Jim Griffin]

Benny,

You asked:

1. If I'm going to build the ported version instead of the sealed, what length do the ports have?
Sorry, but I didn't find any answer...

The specified tube is available from CSS and Parts Express. I recommend the shortest length of this adjustable length port tube (4 5/16"). This would be a 1.375" diameter by 4.3125" long tube. I'm assuming that you can find a close equivalent in Europe.

2. Is it correct, that the two coils, which wire diameters are given in AWG are 1,3 mm (16 AWG) and 0,8 mm (20 AWG)?
A friend told me so, but I want to prove his answers instead of making any mistakes...

Correct.

Jim

[Benny the 2.]

Thanks for your quick reply...
I'm getting a pair of G2SIs at the end of this month, then I can start to build them.

Greetings, B.

[Will]

Originally posted by Jim Griffin
Benny,

AWG are 1,3 mm (16 AWG) and 0,8 mm (20 AWG)

Jim,

What about the exact dimensions of the air coil you used in your design ? Could you please give the following :

For both the 1.5 mH and 0.3 mH coils ---> inner diameter and width.

I just want to build the exact same coil.


Thanks.



Will.

[Benny the 2.]

Uuups, I just found one missing information too...

Do I need stuffing material like lamb wool to put into the monitor?
If yes, how much?

And

The specified tube is available from CSS and Parts Express. I recommend the shortest length of this adjustable length port tube (4 5/16"). This would be a 1.375" diameter by 4.3125" long tube. I'm assuming that you can find a close equivalent in Europe.

I'm sure I can find something, but I wondered why the parts list with the entire PE- numbers isn't contained in that PDF.
The pipe could be 260-329, is that correct?

Greetings, B.

[Jim Griffin]

The prototypes that I built actually used a 15 awg coil for the 1.5 mH value. It is the Jantzen brand coil that is Parts Express #255-426. That coil is 2.32" diameter x 1.2" high. The 20 awg 0.3 mH coil is P-E #255-028 which is 1.14" diameter x 0.60" tall. The 1.5 mH coil can be either 15 or 16 awg. The 0.3 mH isn't too critical in wire gauge as it has a small resisitor in series with it. Note the inductor placement in the layout included in the pdf file.

On the port tube I used the P-E #260-388. This is an adjustable port tube that is 1.375" dia. x 4.3125" long (I'm not using the sliding part of the tube in this design). Note that Benny's post just above here has the wrong P-E part number.

All of these parts can also be ordered through Creative Sound Solutions or Parts Express.

Jim

http://www.creativesound.ca/pdf/JX92SG2siDesignPak.pdf

[Jim Griffin]

On the stuffing question from Benny let me say that I used a layer of 5/8" thick acoustic foam on the side walls. I use Parts Express #260-516 convoluted foam (1.5" peaks) on the rear wall. No stuffing is used per se.

You can also use other foam treatments like the Sonic Barrier Damping material (P-E parts #260-520, -525, -530 or -535) or equivalents.

Jim

[Benny the 2.]

Thank you so much...

I wondered myself about the port tube, because you wrote 4 5/16", and that was way too oversized...
I found 260-388 by myself, but I couldn't edit my posting any more...

B.

[Will]

Originally posted by Jim Griffin


On the port tube I used the P-E #260-388. This is an adjustable port tube that is 1.375" dia. x 4.3125" long (I'm not using the sliding part of the tube in this design).

Jim,

Regarding the port, was the sliding port completely removed or just positioned at the shortest dimension ?


will.

[Jim Griffin]

I removed the sliding tube.