Fostex FE126En Build
Hi I am new to full range and have not yet heard one.
I have purchased a pair of Fostex FE126En speakers after reading various forums from Wilmslow Audio.
I have had some box's made to the Fostex Spec Standard Bass Reflex Enclosure 15mm Plywood with an Ebony Macasser veneer that I have been polishing with beeswax. They are from a trader on Ebay in Moldova and were a bargain in my opinion.
They are 105L Tuned to 60Hz according to the Fostex Plans.
I know that they will not sound as good as a horn according to the various forums, but what I want to do is learn along the way, get used to the BR and then look at building a suitable Horn once I know more.
What's so bad about the Fostex Hybrid box plan compared to the other designs?
To make this starting project sound the best I can what do you recommend? Please don't say don't bother and start with a Horn strait away. I could do that but the journey of learning is important to me.
I have been listening via commercial Hi-Fi for over 20 years now and feel that the internet forums are giving many of us freedom from the commercialism, snake oil and spin. :D
I am in the process of building a Lenco GL75 TT with heavy plinth and Rega RB300. This has taken me a couple of years to do due to work and family commitments but I am almost there.
I also have a Thorens TD160 and Yamaha YP900 TT for vinyl duties.
I have built a Vortexbox player loaded up with FLAC files from all my CDs as well as having various CD players and Dacs I can use.
I have a 20w SMSDL class D amp, a 40w Push Pull EL34 amp and various SS amps to choose from as well.
At present I am listening to Mission 752 floorstanding speakers and Proac S1C stand mount speakers. I prefer the proacs but they cost 3x as much.
I listen to MOR, contemp country, some classical and film soundtracks, (I love the mellow stuff from Hans Zimmer like the Last Samurai) and love women's vocal and things like Diana Krall.
I don't listen to very loud music, probably about the 10 0'clock position on the amp volume.
Back to these speakers, I have bought the drivers from Wilmslow audio along with Monacor MDM-3 lambswool stuffing for the speakers.
I am looking to use some high quality silver plated OFC cables that I have in the box.
The listening position is approx 9ft away and my current speakers are 5ft apart although they could be 9ft apart
Can you please help me with some of these questions before I start to assemble:
As its a BR Box do I need to us a resister for the FE126En to tame it?
How much stuffing / damping of the BR box is required?
What mods should I make to the speakers?
(I cannot find 'Duct Seal' on Ebay or in any hardware shops in England)
Is there a gasket that needs fitting between the speaker and the box?
Any advice on using Cones or Bluetack on the Partington Dreadnought speaker stands?
Any tips on getting the speakers just right before committing and screwing them into the box.
I will run them in for a 100hrs before any listening, using a burn in CD on FLAC. Should I do that for a constant 100 hrs or limit the times to burn them in?
The next project later this year once my Lenco is finished will be to build a horn enclosure.
Any early advice to start thinking, dreaming, researching about would be good. I don't think I would be able to get away with a kongo or other similar tall horn due to WAF but you never know ;) so may be looking more at the more compact horn enclosure.
I know much depends on the room and WAF
Ye gods, that's a battery of questions. I don't think many people have the time to answer quite that amount from a single post. I'll do my best since I've a few minutes over my lunch hour.
That is some beautiful veneer. Also, the bellmouth vents made of wood look really nice. I can't believe you have not stuffed the drivers in for a listen yet! :) I have heard some very nice things about the FE126 in a Frugelhorn Mk3 (FH3) - lots of threads on it - do a search and you will find it. But if you want to try this driver in a nice horn, that would be a good place to start.
Thanks Scott for taking the time out of your lunch hour to answer. Its my day off today probably why I got a bit carried away with the questions.
What's a shelving filter? Is it a resistor in parallel and what value type do I need and where and how do I fit it? I presume I solder it?
If I don't use self tapping screws can you put in the right direction what to use and where I can get them from?
I bought the self tapping socket hex head screws below
This is all new to me so I really appreciate the advice :)
I have been tempted to try them out but I am looking forward to assembling them with all the parts in one go due to lack of time.
One day I will build a horn later this year once I have some hours under my belt with this.
I do like the cabinets, I have put beeswax on them and been polishing like mad, which is after the picture was taken. I will post once its all in situ.
I liked the shape of the FH3 so much I was inspired to build a small homage to it out of foam core. It actually sounds quite nice and is one of my favorites. Here is what I ended up with using a TC9FD driver. http://www.diyaudio.com/forums/full-...ini-build.html
I hear that the FH3 flatpacks are a relatively painless build - takes a lot of clamps more than anything.
Hi have looked on here
Loudspeaker Diffraction Loss and Baffle Step Compensation Circuits
Re is the DC resistance of the driver voice coil [ohms],
Wb is the width of the baffle [inches],
dB is the amount of attenuation required [decibels],
f3 is the frequency midpoint of the transition from 4π space to 2π space,
Lbsc is the calculated baffle step correction circuit Inductor [mH] and
Rbsc is the calculated baffle step correction circuit Resistor [ohms].
Put in the info on the calculator
Re 8 [ohms]
Wb 7.08 [inches]
This is what it gives me
f3 644.1 [Hz]
Lbsc 88301.7 [mH]
Really sorry to be thick and hopeless, what do I now need to buy?
Re is the actual value (7.2), not the nominal impedance (which means nothing). The amount of attenuation you enter is the number of dB you need to lose from the output. In this case, I'd aim for the full 6dB since you're not just needing to compensate for step loss but the inherently rising response of the 126 drive unit. The tradeoff for obtaining a balanced response is that total sensitivity drops.
More realistic values are 1.8mH paralleled with 7ohms in the hot lead.
Awsome how do they sound?
I have looked online for the FH3 kits i think the postage makes them prohibitive as I can't find them in the UK only in the USA
My little foam creations sound great - I love them! The imaging is fantastic, the vocals are my favorite aspect, and the bass extends down to about 60 Hz and is sufficient so that BSC is not required. I have not heard what a real FH3 sounds like but can only imagine it is much better if using a larger and higher quality driver in a wood cabinet. I believe there are FH3 flatpacks available in the UK. Planet10 or Scottmoose can point you to sources.
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