Are Fostex FF85wk or FF105wk suitable for TV multimedia speakers?

Hi Everyone.

I have found this forum while looking for suitable speakers for my TV. I have been using an old Altec Lansing CS21 system and it sounded really good. Unfortunatly it as died, and the tv sound is pretty horrible in comparison. I used it for concerts on youtube ,spotify and netflix.
I do have some space restrictions,and while looking for speakers I came across the Fostex DYI kits. Not only they would fit in dimentions ,as i could finnish them to match the rest of the house (WAF is an issue..).
That being said,i have no way to demo them before buying ,and i am a bit afraid that they will sound worst than the Altec Lansing system .
I was thinking in one of this kits:

Fullrange loudspeaker kit Fostex FF85WK, with cabinet kit plywood 18 mm thick

Fullrange loudspeaker kit Fostex FF105WK, with cabinet kit plywood 18 mm thick

Do you guys think one of theese would suit my needs?

In my computer I use a single Ikea Eneby20 speaker and i am totally ok with the sound ,so i'm not super picky.

Thanks in advance for your atention,and congrats on a very nice forum.Really made me wanna get into this hobby!
 
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those drivers are suitable. Those boxes are way overkill for these drivers. The boxes are both too big for the drivers and the vents are suspiciously large. It is possible to put some space filler nto the box and to install a more approriate size vent.

Smaller driver uses a box 1.5-2.5 litre, the 4” about twice that.

Often an attempt to get maximum bass out of them.

The larger driver will get a bit more bass, and play louder, but is not quite as good mid/top as the smaller driver.

I have outlined in a couple places some simple mods that work to reduce the few issues these drivers have and to step their performance up a level.

There is a good, fairly recent thread on the FF85 that has a lot more info. Implementation of Fostex FF85wk
 
Thank you for the reply. I had noticed that the vents were bigger than usual,even though they are 43mm at the beginning and get wider. The thing is that those boxes would cost me the same as the Fostex Kanspea ones ,would they be better still due to better materials or the design doesn't make sense?
Building one myself will have to wait because i need to get something up and running.
I would be using a subwoofer , and given that there will be movies and hiphop playing, would you still prefer the FF85wk? Or in that case would the FF105 be a better match?
Thanks in advance
 
To expand on Dave’s comments above, having built a fair range of enclosures for both models cited above - more for the ‘85 than ‘105 - I’d opine that the use of 18mm plywood is a bit of overkill; most of my dozens of builds for those where 15mm Baltic birch. If you have any DIY wood bashing skills at all, I’d suggest the Woden Baby Lab design for whichever of these two you might decide on.

What amp would you be powering the new speaker with? The 2 channels on board the CS21 sub module might not play all that well with the Fostex, or should I say any shortcomings the amp might possess could very well be highlighted.

Edit: upon reading your recent reply, I’d suggest the 105.
 
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Thank u Chris, I would like to get something up and running for now so i can have decent sound again ,then with calm go down that road and build something cool.
I will be getting a new amp and subwoofer. I was thinking of something like the SMSL SA300 and for subwoofer i was thinking of something like the Fostex PMsubmini 2 ?Or would you sugest any other pairings?
Dave what adaptations would you sugest ?
Thanks once again for the help and knowledge.
Miguel
 
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Ob1; IMO as with many request for recommendations, the intended application (room size, etc) and budget would be near the top of my decision tree. To be honest, it’s been probably a decade since I had the opportunity to audition any 2.1 integrated amp - and those I did we’re not ahem, not quite the degree of transparency and dynamicism I was looking for at the time. Indeed, I’ve long since abandoned subs with built in power (plate) amps.
So, the next question on my checklist would be: what will be the primary program source(s)? I’m currently going through the exercise of selecting components for my son’s upgraded living room HT system, and since it’s been probably 5 yrs since the last upgrade to my own, it’s amazing to see how much functionality is built into today’s smart TVs. They’ve not subscribed to traditional cable for at least the same amount of time, and having access to gigabyte speed internet, they are able to stream more content than as a young working couple they have time to consume.
He’s been deeply invested in the Sonus ecosystem for a while now, and while not inexpensive, they do offer some pretty nice features and a degree of lifestyle convenience that I think Bose wishes they could have found a way to patent first.

While I’m currently rocking an older Onkyo surround receiver with more bells and whistles than I now need, if I was starting from scratch, I’d look very closely at systems like the new NAD C700, with sub(s) powered by external amps. Regardless of any remnants of audiophile nervosa in my mitochondrial DNA, this application is one where I’ve yet to hear any deficiencies of recent class D amps. Currently running Hypex UCD 180 on subs, 3 channels of ICE power A200 on the front row trio, and the Onkyo’s amps for rear an front row surrounds. If I was able to scrounge sufficient change from the couch cushions - so much harder these days with Apple Pay on our phones- I’d go for Neurochrome Modulus 686 up front, and 286 or 186 for the surrounds.
 
I bought the Kaspea box and 105 "kit".
It's true you can definitely build better yourself but I was surprised how easily I forgot about it in use. It is inexpensive, works fine with the driver and looks OK. I think it is just 6mm particle board or similar. So you can definitely do better but you may decide it is not worthwhile if you just want it for TV.
 
Chris: The Altec CS21 were my computer speakers in my old house. In the living room I used an Denon receiver with Wharfdale's 9.1 . I live in a really small house now (under 40 square meters) and can only acomodate a 2.1 system ,and a small one at best. I know the Altecs were a simple system, but I always loved how they sounded,and with the sub they really filled the room (roughly 4m x 3m). So i'm really looking for a replacement,all i would like to add is bluetooth ,and i would like to buy separates, speakers + amp+ sub . The speakers need to be close to the wall and not too deep (20 cm max),and not to wide (less than 16cm) so they can fit next to the tv, that's how i came about to the Kanspea.
I would prefer to buy a little amp unit like the smsl sa300 or other small amp (budget 150€ max) and a separate subwoofer (max 180€) for the low end for movies and some types of music. I liked the size of the Fostex Submini , do you think it would complement the ff105 ? i need something faster and more musical rather than movie boom blasting.
Sources will be the smart tv (they are amazing nowadays) and phones over bluetooth.
I dont think Sonos is the way to go for me, i wanted a simpler (cheaper hopefully) amp+speakers+sub. And for the amp i would not go DIY.
Loved the design u suggested for an enclosure, but i need something front ported because they will be close to the wall.
I guess i will start with one of those kits,then with time do something cool to fit the space.

Tsardoz: Looks are definitely a factor ,but i think the Kanspea looks are totally ok. My doubt is that it would cost the same as that thick wood flat pack kit .Even if the design is not ideal,maybe the flat pack would still be better? Maybe with some adaptation?
Even if i go for the Kanspea kit i will paint the boxes, and in the future i will build some boxes for sure,but i do need to read a lot before that,so for now i will choose the kanspea or the flat pack kit to get some sound. Which would u choose?

Thanks again for all the help
 
I had Kef Eggs for my PC which annoyed me too much when they turned off.
Otherwise they were great speakers.
I bought the Kanspea mostly as a gift for someone but used them for a few weeks first. The box was better than I thought it would be. I really liked this speaker but it lacked bass (to be expected).
I have since bought Scanspeak 10F/8414G10 drivers and paired them with this box

IWISTAO 3~4 Inch Empty Speaker Cabinet Full Range Multilayer Board Drum Shape Internal Wave Pattern HIFI Audio DIY|Bookshelf Speakers| - AliExpress

The speakers are not broken in yet but I think they are on a par with the Fostex. I think Fostex are better value.
I would not spend so much on an amp.
I have just ordered a whole bunch of these:

WONDOM | STORE

They make several others too but the JAB5 has serious bang for buck and is more flexible.
I have tried many of the Chinese class D amps and most are rubbish. So easy to design too - just copy the manufacturer's circuit but they insist on making changes which just make them worse.
But there is something about these WONDOM amps that makes me think they have been designed by a decent engineer (I am electronic engineer BTW). I guess we will see. Huge bonus is Analog Devices DSP onboard so you can do your own EQ using SigmaStudio. The JAB4 is lower power and lower cost and will also do 2.1. This integration makes it cheaper overall than MiniDSP. SigmaStudio has a bigger learning curve but you can do far more with it.
Fairly simple to then just build a box for a subwoofer and throw a driver into it. I have bought a whole bunch of 6.5 - 8 inch drivers recently to try out and think the MCM represents the best value. They won't go super loud of course but if you are buying 4" mains I would guess that is not a priority.

EDIT: I see Farnell are in Portugal. I bought this one https://pt.farnell.com/mcm-audio-select/55-5665/6-5-die-cast-woofer-8-ohm-rubbber/dp/2827722
Most of the others are not long throw and not suited for a sub.
 
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Ob1; my mention of Sonos in combination with the newer smart TVs was merely to note the significant advances in performance and affordability of wifi/network based home entertainment systems over approximately the last decade. For an old fart who’s been trying to wean himself from an almost 60 yr audio addiction*, it’s been quite a journey from that RCA mono console in my folk’s basement to where I am today. I shudder to think of how much time and money I wasted during the ‘70s to early ‘90s riding the crazy upgrade carousel, with the very patient and bemused acceptance of my long suffering wife.
From the situation you describe a small 2.1 system sounds like a very practical goal. There are numerous small enclosure designs for FR drivers by most of the major brands available to DIYers, many of which are front ported; Dave Dlugos’ milliFonken for Fostex series among them. On second thought, the ‘85WK, with the support of a small sub crossed over between 80-120Hz could be a very workable approach.
As you didn’t mention budget for this replacement system, it’s hard to make suggestions that might exceed your current reach.

* as a charter member of the recovering audioholic community, I’ve been very much enjoying Andrew Robinson and Kristi Wright’s YT channel, and this recent video might be of interest. HiFi Starter Kits!! TOP SIX Home Stereo System UNDER 1000!! - YouTube

FWIW, it was their recent review of the NAD C700 that piqued my interest, but no doubt there are other product offerings with similar feature sets and perhaps at more affordable prices to those who might be budget constrained. My upstairs “background” system is an older Marantz M CR611, which is a nice enough piece, but lacks the operational flexibility of many of the newer models, and with the combination of streaming and music libraries accessible from two separate Mac Minis, I don’t think I’ve spun a CD in its drive more than twice in the past couple of years.

and once again, I’m rambling on vacuously; enjoy your trek. 😀
 
Tsardoz: The new speaker must look great with those boxes! Thanks for the amp and sub sugestions, but i think i will go for something more ''already done'',that seems to be way above my know-how. Did the subwoofer helped the sound of the ff105?

Chrisb: I literally had seen the video you sugested half an hour before!
I also dig the cheap audioman videos.
But i would like to spend less on the amp than in the video,my budget would be 150€ max. For the sub i thought 200€ max.
I have decideded to use the ff85wk ,gonna follow all the advices. Would the minisub from Fostex be a good match?or do you have another sugestion?
And for the same price i can take the Kanspea or the thick would assemble flat pack :
Fullrange loudspeaker kit Fostex FF85WK, with cabinet kit plywood 18 mm thick

Wich one would you guys go for?For the same price i'm inclined to go for the flat pack,unless you guys think that it's so badly designed that it would sound worst than the Kanspea. The measurements of the flat pack seem closer to the recomended measurements on the driver specs list ,exept for the duct size..
The Arylic seems to be great,but i think it's a bit more expensive than i would like,and has some functionality that i don´t really need. Would it sound better than the SMSL sa300 for example?
Thanks for all the help
Miguel
 
Miguel, not having heard it, I can’t speak on the subject of the Fostex mini sub.

Between the two speaker kits you cited, perhaps it’s my elitism talking, but as both seem to me compromised or poorly designed, I’d be inclined to go for whichever of the two would land at your door at lower cost - you’re in Portugal, I think? If you find them satisfactory and have some modest woodworking skills, you could always build something like a Planet10 microFonkens. Attached picture of a pair with the earlier model of FF85K for sense of scale.


http://p10hifi.net/FAL/downloads/uFonkenWK-1v0-plan-130312.pdf

The more I think about it, the little Arylic A50+ is looking more interesting. It appears to have sufficient power for small room/near field ( I’ve been using a pair of FF85WK with Topping TP30 amp as computer speakers for at least 5 yrs and am more than happy with the performance) and includes a line out for sub; although the XO frequency is not stated anywhere I could find.

As with the Fostex sub, I haven’t heard the SMSL - or the Arylic for that matter- so any comments regarding the relative merits of either would be supposition.
 

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I think most subs would work well in a FAST system with drivers of this quality provided they are set up well. I do not have any knowledge of the cheaper commercial ones though. Certainly the ones I have made have made them sound great with appropriate setup.

The boxes from Aliexpress are pretty good - they have a few little dings which is disappointing. I botched up the finish on them due to inexperience with finishing. They are made from stacked CNC cutouts of veneered ply. I elected to leave the striped finish on the side as I liked it. I just painted polyurethane on and it looks good. The top I used stained hardwax oil which I think is great and very easy. But I mucked up the staining part - should have wiped it off but left it on and it dried unevenly. But the hardwax oil is great - I will definitely use it again - they say it is idiot-proof (I proved them wrong). Next time I will fill holes with wood putty before staining and sand everything down. Then apply stain and wipe it off. Then the final coats. It does not need sanding between coats which is a bonus. I have 5 subwoofers I am building (4 to go to friends as presents) so want to make sure the finish is good.

I also mucked up the front. I sprayed black acrylic on which went OK. Then I painted a few coats of PU over it but for some reason it all started peeling off. Note to self - don't do that again. Not sure why it happened.

Here is photo of one of them. You can see some of the issues I mentioned. Maybe one day I will try and fix but I don't really care TBH. I need to be more careful for the presents.
 

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I just quickly modelled that box, vent and enclosure.

I get the internal volume as being about 3.6 litres (not accounting for port and driver).
Downloading specs from here Fostex FF85WK - 3.2" Full-range

using QSpeakers (quick and easy) gives optimum enclosure volume about 2.9 l
The port is this one

4cm diameter QSpeakers says it should be optimum of 15.7cm long for f3dB of 76 Hz.
The port is only 11cm long which would make the 3dB point around 79 Hz allowing 300ml for port and driver volume.
This all sounds about right to me. You can do your own modelling using whatever software you like. This will vary depending on what you stick inside it. This enclosure is definitely better than the Kanspea. If you are not expert at finishing (like me) try the hardwax oil on the ply.
 
Hey I just noticed the Xmax of that driver is only 0.35mm.
I think this would make it unsuitable in this type of application as a full range driver. It exceeds that even at just 1W.
I would definitely go for the larger driver if you can afford it (FF105WK)

Geez I am playing my ScanSpeaks now with this amp while I wait for the Sure Electronics amps and they still sound great. You can get them boxed too. Make sure you get a 4 ohm subwoofer though if you are going passive. There is some noise on the line in input but the Bluetooth works well believe it or not. Of course if you are not getting a passive sub you do not need the extra sub amp.