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PostPosted: 21 Jan 2013, 23:13 
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Joined: 28 May 2008, 21:53
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Location: Winnipeg, CANADA
Having recently moved from an apartment to house I now have a few rooms that require some sort a stereo setup. One of them is a small office with a desktop computer system. I was looking for a smallish pair of bookshelf speakers to be used with the computer as near-field monitors. The primary use will be listening to music while working / playing on the computer. For an amplifier I will be using a Topping TP23. This is a 25WPC class-T digital amplifier with USB input. http://www.parts-express.com/pe/showdet ... er=310-334

For the bookshelf speakers I decided on using the Fostex FE103En fullrange driver. With a fullrange driver I won't need a crossover filter and since they will be used near-field a baffle step compensation filter will not be required.

For the enclosure I decided to try out the Bass Reflex plans that come with the Fostex FE103En fullrange driver datasheet.

I did a number of little modifications and tweaks to the Fostex FE103En fullrange speaker drivers.

And a couple of photos of the speakers.
Attachment:
Fostex-FE103En-Bookshelf-Bass-Reflex.jpg

Attachment:
Fostex-FE103En-Bookshelf-Speakers.jpg

To test out the speakers I have been using them in the family room connected to a 2012 Dennon A/V HDMI reciever. The player is a Oppo BDP-83 and the other component is a Panamax mains voltage regulator / filter / surge protector. Behind the chair is a 10-inch (250 mm) diameter subwoofer in a sealed enclosure to fill out the bottom end. The speakers work well well used in this role. I use the A/V to set the crossover point between the sub and the speakers.

I'll be trying the speakers out in the office soon, so more notes to follow and eventually a project page.

Cheers


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PostPosted: 21 Jan 2013, 23:26 
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Nice looking house with bright rooms, eh? :D

You get some ideas from Dave for outfitting?

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PostPosted: 21 Jan 2013, 23:47 
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Thanks! Don't let the bright sunshine fool you. It was about -31 Celsius (-24 Fahrenheit) outside and windy! Gregg, I'm sure you still have nightmares of the long cold Winnipeg winter nights! :cold:

Cheers

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PostPosted: 22 Jan 2013, 04:42 
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I do! :cold:

I almost feel guilty having sun and +6C this past weekend 8-)

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PostPosted: 08 Apr 2013, 17:53 
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So I have had these little speakers going with the desktop computer in the office for a few months now and I am really happy with the results. The speakers are powered from a Topping TP23 (25WPC class-T). Since they are used in the nearfield, there is no need for a baffle step compensation filter. In the farfield, the BSC really robs the drivers of the detail and magic that draws us to these sorts of drivers in the first place.
Attachment:
Fostex-FE103En-Nearfield-Monitor-Speakers.jpg

Cheers


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PostPosted: 08 Apr 2013, 21:17 
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Joined: 06 Jun 2008, 18:23
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Location: Australia
Two things: 1, -31C is crazy cold and 2, Those speakers look cute. Love the timber finish and timber port. Very nice.

I've been playing my FE206s in the double bass chamber a fair bite over the last few weeks with the 1/2W amp. I like them but some of my other audiophile mates claim there is no body to the instruments and of course not a lot of bass. I must try and dampen the bottom chamber and see if the that improves the speaker. When I had the speakers tested there was a lot of mid range coming out of the port.

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PostPosted: 14 Apr 2013, 20:46 
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Mark - be sure to send an update about how damping the bottom works out.

I've just posted a writeup for this project: Fostex FE103En DIY Bass Reflex Bookshelf Speakers (Nearfield Monitors).

Impedance sweeps and frequency response measurements to follow shortly.

Cheers

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PostPosted: 11 Aug 2014, 18:10 
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Location: Australia
Hello from Australia.

I've been planning on building some speakers for quite some time and the combination of relative simplicity, good looks and the fact you can actually get these drivers in Aus has me sold.

Being fairly green on the topic I have one thing holding me back from ordering parts.
I believe I understand everything on the plans bar the hole size for the port. I assume the 93 mm suggested for the top hole is the correct size to fit the drivers but the 50 mm hole for the port I must assume is the suggested internal port diameter. Is this correct?
I have located 50 mm ports that require if I remember correctly a 63.5 mm hole and to be cut down from their 100 mm length.

Your help would be greatly appreciated.

Thanks in advance.


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PostPosted: 17 Aug 2014, 21:19 
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Location: Winnipeg, CANADA
Hi, sorry for the late reply. The port is to be 50mm diam by 60 mm in lenght - internal dimensions. What I would do is get the port diameter closest to the intended diameter and adjust the port length to arrive at the same box tuning.

Cheers

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