Den,

The DX3 based LT-2000 MkII is only slightly bigger (fatter, actually) than the
FT-1600 MkII. The DX3 has a decidedly different sound than the FE167E. Clearer,
more air and a bit edgy. If you want the same sort of sound as the FE167E's, but
with more guts, you might want to consider the W8-1772. It has the air and
detail of the DX2 and PM6C but more meaty. I guess it depends what you are
listening to. I like the TB much better than the FE207E/FT17H combo.

Bob

--- In brines_acoustics@yahoogroups.com, "najuchd" <bacobits1@...> wrote:
>
> Wow, I'm surprised Fostex is discontinuing the 167E too. There has to be some
kind of substitute out there. I very much like my FT1600II's. Will a Lawther DX3
fit in the the same space?
>
> Den
> >
>

Folks,

I have had too many spam posts lately. So....

Effective immediately, I am enforcing moderation. I will approve of all posts
prior to inclusion. In the past, I have been receiving posts as daily
collections. Now I will receive each post for approval. For those of you who get
collectives, you should see no change. Your individual posts may be delayed a
bit.

Sorry for the inconvenience, yada, yada.

Bob

Hello there!

I have being making ported enclosures for about ten years. I used to do it
commercially while I was in engineering school and now I make them as a hobby. I
have a four step system. First I use a speaker modeling software for the
preliminary tuning of the enclosure, then I make a virtual 3-d model, then I
build the enclosure and finally I empirically tune the system according to the
environment and user preference.

I can easily empirically tune a ported box by stuffing and changing the port
length. But I'm a lithe worried that once I build a transmission line enclosure
I am stuck with it. I know that I can lower the tuning frequency to some extent
by stuffing the line, but I won't have the flexibility to tune up and down that
I am used to, so I have some questions.

• How forgiving and flexible are TL enclosures in terms of their design?
•  How critical is the tuning frequency of a TL enclosure for SQ and SPL?
• Do I have to tune it to the resonant frequency of the driver?
• Should I make the line shorter that in Ό wave theory and then tune it down
empirically by stuffing.
• How can I calculate the minimum cross sectional area of the line to minimize
enclosure size?
• Is there any tutorials or free software that I can try?
• What about mass loaded T lines? Any design tutorials or software for that?
• Are TL designs suitable for large subs?

Sorry for having so many questions and thank you very much for the opportunity
to ask then. I would really appreciate any help for pointing me in the right
direction of my first TL speaker system.

It appears that you have been reading the old, out of date material on TL's. All
of your questions are answered in Martin King's tutorials. Go to
http://www.quarter-wave.com/, do some reading the then come back with your
question.

Bob

--- In brines_acoustics@yahoogroups.com, "joselhawayek" <joselhawayek@...>
wrote:
>
> Hello there!
>
> I have being making ported enclosures for about ten years. I used to do it
commercially while I was in engineering school and now I make them as a hobby. I
have a four step system. First I use a speaker modeling software for the
preliminary tuning of the enclosure, then I make a virtual 3-d model, then I
build the enclosure and finally I empirically tune the system according to the
environment and user preference.
>
> I can easily empirically tune a ported box by stuffing and changing the port
length. But I'm a lithe worried that once I build a transmission line enclosure
I am stuck with it. I know that I can lower the tuning frequency to some extent
by stuffing the line, but I won't have the flexibility to tune up and down that
I am used to, so I have some questions.
>
> • How forgiving and flexible are TL enclosures in terms of their design?
> •  How critical is the tuning frequency of a TL enclosure for SQ and SPL?
> • Do I have to tune it to the resonant frequency of the driver?
> • Should I make the line shorter that in Ό wave theory and then tune it down
empirically by stuffing.
> • How can I calculate the minimum cross sectional area of the line to minimize
enclosure size?
> • Is there any tutorials or free software that I can try?
> • What about mass loaded T lines? Any design tutorials or software for that?
> • Are TL designs suitable for large subs?
>
> Sorry for having so many questions and thank you very much for the opportunity
to ask then. I would really appreciate any help for pointing me in the right
direction of my first TL speaker system.
>

I just got word that the link to the construction techniques page I send with
plans packages has expired. the correct link is
http://www.brinesacoustics.com/Pages/Articles/Cabinet_Construction/Construction.\
html.

Sorry for the inconvenience.
Bob

Hi, y'all,

I just posted this information as a "Late Revision" on the web site. I am open
to questions and comments.

Bob

---------------------------------------------------


I have received the new FE166En drivers from Fostex. While the new drivers are
not drop-ins for the discontinued FE167E, they are suitable for a MLTL type
enclosure. I am currently working on an FT-1600 MkIII cabinet. Early indications
are that this will be a very good speaker, a worthy successor to the FT-1600
MkII. Any new orders for the FT-1600 will be filled with the new FT-1600 MkIII.
However, plans and flats will be available for the FT-1600 MkII for those who
already have a pair of FE167E's.
The FT-2000 will continue to be available with the new FE206En driver. The FE206
was an option for the FT-2000, although I stopped advertising it as such. I have
no reason to believe that the FE206En won't work well. I will pursue this change
after I finish with the new FT-1600 MkIII. Of course, if someone would like to
order a new FT-2000....
The LT-2000 MkII will remain available with the Lowther DX3, as will the TT-2000
with the Tang Band W8-1772. Reference the latter, i strongly recommend spending
the extra money for the W8-1772's vs the FE206En's.
The FB-16 will most likely go away with no replacement. My experience to date
with the FE166En indicates that a bass reflex cabinet would be too small and too
high a cut-off to please me. However, it might made an acceptable home theater
main if crossed at 100Hz or so. We'll see.
The FB-20 is still in question. I have mounted FE206E's in this cabinet with
reasonable success. This will remain well down in my list of priorities unless a
customer demands. I am considering a bass reflex cabinet for the W8-1772. Early
indications are that this may well be a killer mid-sized stand mounted speaker.
It's not top priority, but it there is interest....

I have a pair of these and need some enclosures. Any recommendations?
Thanks

Uncle Dudley,

Well, the 1808 takes a BIG box. I had a fellow ask the same question in private
emails. The solution was a 100L MLTL -- 48"x10"x12" driver 12" down from the top
and 4"diax2" port 5" up from the bottom. And the reason a prefer the 1772 is....

Bob

--- In brines_acoustics@yahoogroups.com, "brinesacoustics" <bob@...> wrote:
>
> Uncle Dudley,
>
> Well, the 1808 takes a BIG box. I had a fellow ask the same question in
private emails. The solution was a 100L MLTL -- 48"x10"x12" driver 12" down from
the top and 4"diax2" port 5" up from the bottom. And the reason a prefer the
1772 is....
>
> Bob
>
Thanks Bob,

I sent the same question regarding the 1808 to TB and here's their response:

type: vented box
       shape: prism, square ( optimum )
       Vb = 65 liters
       V(total)= 66.39 liters
       Fb = 41.41 Hz
       QL = 6.723
       F3 = 47.16 Hz
       Fill = minimal
       Vents = 1 round with ends flush
       Dv = 71 mm
       Lv = 40 mm

Other than the obvious I'm not sure what some of the other numbers mean. Could
you/someone translate for this neophyte?

Thanks again,

Uncle Dudley

Uncle Dudley,

I posted a file comparing a 65L box and a 100L box. The 65L box will be punchier
while the 100L box goes lower. The real problem with boxes this big is that with
reasonable width and depth, these things become floor-standers and are not BR's
at all. There are MLTL's and you need to consider pipe resonances.

I based my statements on the TB published specs. You need to measure your
drivers to assure that they are not wildly different from spec. Then I could use
those numbers to give you a design that I can stand by.

Bob

> I sent the same question regarding the 1808 to TB and here's their response:
>
> type: vented box
>       shape: prism, square ( optimum )
>       Vb = 65 liters
>       V(total)= 66.39 liters
>       Fb = 41.41 Hz
>       QL = 6.723
>       F3 = 47.16 Hz
>       Fill = minimal
>       Vents = 1 round with ends flush
>       Dv = 71 mm
>       Lv = 40 mm
>
> Other than the obvious I'm not sure what some of the other numbers mean. Could
you/someone translate for this neophyte?
>
> Thanks again,
>
> Uncle Dudley
>

Hi Bob

I thought I would give this mod a go. For ease of use can I place a 1uf cap
across the speaker terminals, or do I need to bypass the BSC internally?

Secondly, how does the removal of the acoustic lining directly behind the driver
effect the sound, and which you you prefer?

Thanks Bob

Richard

--- In brines_acoustics@yahoogroups.com, "brinesacoustics" <rbrines@...> wrote:
>
> Richard,
>
> The only cheap tweak that I can think of is to bypass the BSC filter with a
1-2uF capacitor. That will give you more output at the top. However, if you need
more, or you really can hear above 15kHz, the solution is to add a tweeter. I
recommend the FT17H, crossed with ~1uF. Try some values on both sides of this.
Mount the tweeter on top of the cabinet, and expect to point the tweeter into
the wall behind the speaker.
>
> Bob
>
> > ....If I were to change something it would be the top end. The speakers
sound very smooth in stock form, but I would like just a bit more top end
sparkle. I haven't modded the drive units and I am still using the Erse
inductor.
> >
> > If you remember I used 1" fiber glass in the cabinet and there is also a
piece on the rear panel behind the driver.
> >
> > Do you have any suggestions?
>

Richard,

The cap goes across the resistor/inductor of the BSC filter. Yes, you will need
to remove the driver.

You might consider leaving the filter outside the cabinet until you get it
dialed in. Connect one end of the filter to the +ve terminal on the cabinet and
the other to the speaker cable. Alligator clips work fine for testing.

Bob

--- In brines_acoustics@yahoogroups.com, "tripmaster@..." <tripmaster@...>
wrote:
>
> Hi Bob
>
> I thought I would give this mod a go. For ease of use can I place a 1uf cap
across the speaker terminals, or do I need to bypass the BSC internally?
>
> Secondly, how does the removal of the acoustic lining directly behind the
driver effect the sound, and which you you prefer?
>
> Thanks Bob
>
> Richard
>
> --- In brines_acoustics@yahoogroups.com, "brinesacoustics" <rbrines@> wrote:
> >
> > Richard,
> >
> > The only cheap tweak that I can think of is to bypass the BSC filter with a
1-2uF capacitor. That will give you more output at the top. However, if you need
more, or you really can hear above 15kHz, the solution is to add a tweeter. I
recommend the FT17H, crossed with ~1uF. Try some values on both sides of this.
Mount the tweeter on top of the cabinet, and expect to point the tweeter into
the wall behind the speaker.
> >
> > Bob
> >
> > > ....If I were to change something it would be the top end. The speakers
sound very smooth in stock form, but I would like just a bit more top end
sparkle. I haven't modded the drive units and I am still using the Erse
inductor.
> > >
> > > If you remember I used 1" fiber glass in the cabinet and there is also a
piece on the rear panel behind the driver.
> > >
> > > Do you have any suggestions?
> >
>

I have updated the web site to reflect current models.

The FB-20 is gone. In its place, I have introduced the TB-20 BR which uses the
Tang Band W8-1772 driver. Very nice speaker with a great top and bottom and a
good deal of WAF.

The FT-1600 MkIII is introduced using the new Fostex FE166En. Slightly less bass
extension, but a much better top end than the FT-1600 MkII.

I left the FT-2000 up since Madisound still has a few FE207E in stock. Shortly I
will announce a MkII that uses the new FE206En.

I have been playing with the Pioneer B20FU-51W driver. They were on sale for $19
a piece, so I couldn't refuse. This driver is no where near good enough for
inclusion in a commercial product, but it is a good, cheap driver for DIY'ers to
play with you can see what I am doing with it on the page Articles>BOFU.

Cheers,
Bob

Dear Bob
I am new here. I was wondering how one goes about obtaining plans to the above
enclosure for use with the 1772? And what the price of a flat pack kit would be?
Shipping is to NSW 2774 Australia.
Kind Regards
Andrew

Go to the web site/TB-20 page and click the PayPal icon next to "Plans". You do
not need to be a PayPal subscriber, I use them as my credit card clearing house.
Same with flats.

I would highly recommend that you get someone locally to cut your flats. I
haven't looked, but I will wager that shipping will be at least as much as the
flats, and then you will have to pay any customs/duties/taxes on top of that.

I am out of town as we I type this, so give me a couple of days to get plans to
you.

Bob

--- In brines_acoustics@yahoogroups.com, "agcstenhouse" <agcstenhouse@...>
wrote:
>
> Dear Bob
> I am new here. I was wondering how one goes about obtaining plans to the above
enclosure for use with the 1772? And what the price of a flat pack kit would be?
Shipping is to NSW 2774 Australia.
> Kind Regards
> Andrew
>

 

Thanks Bob

no rush - I'll get ono it shortly.

Regards
Andrew Stenhouse

What tools and other equipment (besides the drivers) are needed to build a
speaker from flats? I built a bird-house in the 7th Grade, but that was quite a
while ago. Thanks.

Mr.  Brines, I  happen  to  run across your web page regarding TQWT Cabinets as
used for Lowther speakers. I am interested in building a pair of Lowther
speakers for my home stereo system and would like to hear your suggestions and
advice. is there another email  address  available for you  directly? as the one
linked on your webpage does not work.

Len Deddo
North Bend WA

Len,

It depends on what you want. A BLH will play louder than a MLTL, but won't go as
deep. My speakers are ideal for girl-and-a-guitar, jazz trio, small band
classical. They are good for classic rock. Thay are not so good for metal. I use
them with SS and T-amps. I also power them with a PP tube amp. All work well
with their own particular flavor.

I might point out that the LT-2000 cabinet is rather easy to build. You might
just want to give them a go

Bob

--- In brines_acoustics@yahoogroups.com, Leonard Deddo <lcdeddo@...> wrote:
>
> Mr.  Brines, I  happen  to  run across your web page regarding TQWT Cabinets
as used for Lowther speakers. I am interested in building a pair of Lowther
speakers for my home stereo system and would like to hear your suggestions and
advice. is there another email  address  available for you  directly? as the one
linked on your webpage does not work.
>
> Len Deddo
> North Bend WA
>

Mr. Brines,

On Jan 13 2011 I clicked on the "buy now" button to purchase plans for your
FTA-2000 design.

To date I have not received any information and Paypal notified me that the
payment status is "unclaimed".

Could you tell my the procedure to order please.

Francois

Francois,

I checked my email and my PayPal account. I found no record of you order. If
PayPal has charged your account, you need to have that charge removed.

Yes, you should click on the "Buy Now" button. That should have taken you to
PayPal and charged your account or credit card. If not try again and report the
results here.

Sorry about your troubles.

Bob

--- In brines_acoustics@yahoogroups.com, "francoisgrobler"
<francois.grobler@...> wrote:
>
> Mr. Brines,
>
> On Jan 13 2011 I clicked on the "buy now" button to purchase plans for your
FTA-2000 design.
>
> To date I have not received any information and Paypal notified me that the
payment status is "unclaimed".
>
> Could you tell my the procedure to order please.
>
> Francois
>

Bob, have you ever had the chance to work with the AER MK1 driver? I have a pair
here from a buddy that is looking for a design.

Any thoughts would be appreciated.

Sory, never had a pair to play with. If the specs in the manufacture's site are
to be believed, a MLTL or a strongly tapered TL might work.

Bob

--- In brines_acoustics@yahoogroups.com, "ejfud" <geneberg@...> wrote:
>
> Bob, have you ever had the chance to work with the AER MK1 driver? I have a
pair here from a buddy that is looking for a design.
>
> Any thoughts would be appreciated.
>