Help with first build (FF165WK?)

Skree

Member
2011-06-29 2:10 am
Hi

Am wanting to embark on my first speaker build. Currently, I have a pair of Kef C10 (1985) bookshelf speakers which replaced a pair of rubbish eltax floorstanders when I had to downsize recently. Amplification is a TA2020 Class T amp (rated 45w, probably closer to 25 before distortion) although i am very interested in the little 6-7w TA2024 etc amps if i end up with speakers that sensitive. It is because of my interest in low power audio that I am looking at such drivers.

I want to build a pair of desktop speakers approximately 60x30x30 (HxWxD CM) that have sound quality a significant step up from the Kefs, but with a bit "larger scale" sound, like the floorstanders i used to have, had in abundance. They effortlessly filled the (11'x10') room with a wall of sound and I miss this. I want to create an impression of it when sat at my desk.

I've done some research, and have seen people say that their full range builds needed no BSC or other components between amp and driver. If this is possible, I would like to achieve it. I like this from a cost and sound quality perspective.

I've also done a little reading on transmission line mathematics, not enough to go ahead with a design yet but enough to wonder if a T-Line with its bass tuned down a bit is possible in the footprint i specify, and if they are a good choice for this use. I like the idea of T-Line for probably the daftest reason ever to choose a cabinet type but the idea intrigues me

The other choice as far as i can see is take the reference bass reflex plan for whatever driver i choose, and make it a bit taller to fit the size i need, if this is possible without ruining the sound (i know nothing about bass reflex cabinets)

To get the larger scale sound, low bass response, and higher sensitivity i am after, i am considering drivers ~6" such as Fostex's FF165WK and maybe FE168ez but i've no idea what they sound like or how to interpret the datasheet info to get an idea of this. I guess i'm after a fairly well balanced frequency response.

That's a lot of advice i need so i think i'll leave this post there :D anyone got any help for me?
Thanks
 
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I own both the older Fostex 165k and 168z full range drivers. They are both excellent, musically satisfying drivers as long as the bass response is full. If you build bookshelf sized speakers with these drivers I'd recommend adding a subwoofer for bass support. If you build a back horn (like a BIB) you won't need bass support in an 11' x 10' room. But I'd recommend placing the speakers in the corners. My favorite box for the 6" Fostex 168z is a large bookshelf (that must be placed on the floor) tuned to approximately 60Hz. This combination provides a great bouncy bass sound that easily fills my bedroom with music.

https://speakerprojects.wordpress.com/2015/04/27/fostex-168z-projects/

If history holds true, the 168 will sound warmer than the 165. Let us know what you decide to do.
 
Having both the FF165wk (as well as the older model) and the Alpair 10.3 I would agree with Greg. Much better bass on the Alpair and pairs better with digital amps, IME. You may want to look at a TPA3116d2 or such amp for a bit more power, although I find I do not need it. The Pass ACA amps sound great with the Alpairs but much less gain.

For more money the Eikona looks ideal for your situation. I say choose a proven box with dimensions you like and then choose the driver. You may be able to fold an MLTL, like the one GM or Jim Griffin did for the Alpair 10.3, and get pretty close to your ideal dimensions.
 

Skree

Member
2011-06-29 2:10 am
Alpair 10 looks good. It isn't any more sensitive than my Kef C10s though which would worry me bearing in mind my TA2020's meagre output. Am probably limited to about 25w - the 88dB Kefs go pretty loud.. but they can take everything my amp can give until it starts distorting.. i'm trying to get a "bigger" more room filling sound

I'm open as to cabinet design as long as it fits within my projected footprint (ish), just considered reflex because it looks easier to build and i know it sounds reasonable when used as a desktop speaker.

Open to BSC as well, but if there is an existing cabinet design that fits my space and combines with a particular driver and doesn't need one, i would be interested in it.. just like the idea of not having any potential sound degradation and saving the cost of having one
 
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Another cabinet to consider is a Karlsonator. It fits within your size requirements, and the BSC is built into the design. The level of construction complexity is higher, but you won't need any electrical filters or EQ to get good bass and a balanced sound.

This was actually the first version. I initially did some kluged modeling for an FE166, but IIRC it looked OK with the FF165WK as well. xrk971 has since developed a vastly more accurate way to model these in AKABAK.

https://plus.google.com/photos/100545049816297868412/album/5351016021933523377/5900892856466880930
 
Amplification is a TA2020 Class T amp (rated 45w, probably closer to 25 before distortion)

Closer to 7W.

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a pair of desktop speakers approximately 60x30x30 (HxWxD CM)

Pretty big for the desktop. Based on 15mm material about 41L and over twice the volume i would use for a reflex (our FF165wk boxes max out at 17L)

I've also done a little reading on transmission line mathematics, not enough to go ahead with a design yet but enough to wonder if a T-Line with its bass tuned down a bit is possible in the footprint i specify, and if they are a good choice for this use.

For a TL your box size Might be large snuff… i don't have a TL handy to measure but internal FHXL volume is about 56L.

FF165wk works well in FHXL. We fit FF165wk, or 1 of the 2 Alpair10 into them. I would give the A10s the technical edge in terms of sonics, but FF165wk probably has the edge with rock & roll. FF165wk about 92 dB, A10p 90 dB, A10.3 87 dB.

The other choice as far as i can see is take the reference bass reflex plan for whatever driver i choose, and make it a bit taller to fit the size i need, if this is possible without ruining the sound (i know nothing about bass reflex cabinets)

Be careful with the Fostex recommended boxes … the best of them i have heard ar mediocre.

To get the larger scale sound, low bass response, and higher sensitivity i am after, i am considering drivers ~6" such as Fostex's FF165WK and maybe FE168ez

FE168e∑ really needs to be in a horn.

dave
 

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Skree

Member
2011-06-29 2:10 am
Er, correction, TA2022. It's a Topping TP-60.

Looking at the available options, and being informed that the Alpair 10.3 is more suited to my requirements. A very brief google came up with some possibilities i think could work - such as the mar-ken, on a short stand.

I don't really like plastic bass ports aesthetically. I do like the price of the alpair drivers. I'm just a bit concerned i won't get the increase in (i'm struggling to find the right term) size of sound i'm after out of a driver that isn't any more sensitive than what I have already.
 
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I don't really like plastic bass ports aesthetically.

I don't like them from a performance point of view. T/S parameters are dynamic and change with level (whether in your volume control or the dynamics of the music). With a cyclidrical vent you have a tight tuning and low tolerence to those changes (ie the tuning is off more often than it is on). The added R in the mar-ken gives the box a much larger tolerence to those dynamic changes.

I do like the price of the alpair drivers. I'm just a bit concerned i won't get the increase in (i'm struggling to find the right term) size of sound i'm after out of a driver that isn't any more sensitive than what I have already.

The A10s are very good FR speakers. The lack of XO, not the efficiency is what will give them the edge over your current speakers… and nearfield that everything is coming from 1 physical spot gives them a further edge.

If you are looking for maximum image/soundstage consider getting EnABLed drivers, as that is one area where they clearly bring an advantage.

2.jpg


Althou the differences are 6 of one. ½ dozen of another my personal preference is for the paper cone version.

dave
 

Skree

Member
2011-06-29 2:10 am
Yeah i've been sorely tempted by your EnABLed drivers already. Might work out a bit costly including shipping to the UK and duty/etc though. Perhaps something I can attempt myself later.

Excellent. I've spent a couple of weeks thinking hard and bashing google about this project just to get to the point i feel my questions were good enough, and we have made epic progress in a few hours :D

more work to be done but now i have an idea of a direction, thanks all :)
 
Coincidentally, I have made a Karlsonator as well! :D

Greg is correct, no BSC is needed and you get a big, full sound (this with little 4" CHR70s). I'm not sure if it has been simmed but the Alpair 10.3 would certainly have a lot of bass in this cab. Two of the new 4" Pluvias should be very interesting in a Karlsonator (still smaller than the dimensions you posted).

As Dave states, the Alpair 10p is more efficient and may be a better fit for you. As I said before, folding a Mark Griffin MLTL gets you very close to the dim's you requested (approx 50cm high by 25cm x 25cm) and should sound great (I am planning a build).

Good luck!
 
Glad you like the Karlsonator Giantstairs. :D

That said, I don't really think the 10.3 needs a Karlsonator. They are a bit on the mellow side even direct wired in the simple recommended reflex. They just don't need the mechanical BSC. If the OP wants to do something fancier I'd think perhaps a little folded TQWT would sound a bit punchier than a BR at the cost of some volume. It should be sim'ed first.

BTW I have both the CH70 (currently in mini karlsonators) and the 10.3/reflex as my main speaker systems at the moment.
 

Skree

Member
2011-06-29 2:10 am
Wow the whole Gen 1 2 3 thing is confusing

"recently released paper cone version" - so the A10P gen 1 is actually the latest technology in these drivers?

"folding an mltl" - is "folding" the correct term for "making" or am i missing something? lol. I have looked into the MLTLs, it was enough to tell me i should use a design someone who knows a lot more than me has done, at least for V1.0 of my speakers.. I think some experience will help me in that respect. I am a habitual modifier and tweaker with a penchant for making stuff "just to see if" so it is unlikely i will leave it at one pair of cabs and one pair of drivers (finances permitting)

:D

EDIT: I've been thinking about speakers pair 2 as it is. But to justify fairly large floorstanders to she who must be obeyed i think it would have to be a case of "but these go that loud on three watts, saves electricity!" and a hundred other reasons i would have to get my reasonator working doubletime to think up...
 
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I am suggesting just that -- that you use a proven MLTL, and I have given you 2 examples from well respected designers. 3 if you would like to send a small fee to Bob Brines.

By folding i mean to literally fold the design in half, taking a relatively tall floorstander and achieving the dim's you originally asked for. I'm sure a search for folded MLTL would come upon plenty of results. But if you can go ahead with the straight MLTL it's an easier build with higher driver placement. And if you have permission you may as well go for the Frugal Horn XL.:)

You may even find a flat pack nearby.
 
In this case a straight MLTL so 90 degree angles.

Take a look at the Tabaq and the
Tabaq box for an example.

Greg, just curious what you think of the FF165WK in a Karlsonator? I find it sounds thin and harsh even in a BIB with a digital amp. I tried series resistance but may have to implement baffle step correction. :confused:

Meanwhile my little Karlsonators sounded more robust than a pair of MLTLs with 2 Monacor SPH-60x per channel. At least until I added 6db of baffle step!
 
Wow the whole Gen 1 2 3 thing is confusing

"recently released paper cone version" - so the A10P gen 1 is actually the latest technology in these drivers?


Mr Fenlon and crew are constantly researching enhancements in both performance and manufacturing production design, so yes during the past 10yrs or so that we've seen his drivers, from the initial EL70 to most recent offerings, the "generation" and model numbers have been a bit confusing, and not simplified by some of the special European or Japanese domestic market only editions.

While there are / have been many paper cone models before as best as I can understand it, the A10P is the first in this particular frame size, so it's a Gen 1 - even though it will share some mechanical features with the metal cone model, which has had 2 previous iterations, making the latest a Gen3. Then with addition of "en" suffix designating the aftermarket EnABL treatment, it can be a bit of an alphabet soup.

Either Bob's M10-A10, Scott's Pensil, or Dave's little Compact Floorstander work great with the A10 series, and have as much WAF as I think you'll find with a full sized floorstander for them - in fact my current 7.1 system consists of A10P across the front row in the CFS and a small centre channel.

If you have the floorspace ( I don't) and domestic acceptance, the FHXL is definitely worth consideration as well.