Speaker Talk 2014-16
Read Speaker Talk 2008-2010 Read Speaker Talk 2011-2014 Back to intro page
17th June 2017
The last three months have been very busy. First and foremost due to two new constructions made for ScanSpeak to present their new drivers at the Munich High-End Show, 2017. A classic 3-way featuring the new 11" bass driver, 28W/4878T00, the new 8 Ohm Revelator midrange, 18M/8631T00, and a 2-way stand-mount from brand new Ellipticor drivers. The latter not least exiting due to elliptical voice coils, something never seen before. I very much look forward to more constructions with these exiting new drivers. The 2-way presented in Munich will be launched as a kit around August 1st.
Already around Christmas 2016, the new
ATS4-HE was initiated and finally launched a couple
of weeks ago. This is the most ambitious and expensive speaker I've ever
made - and has brought me closer to the live performance than anything
else I've ever had i my living room.
What characterises two of the new constructions is the use of DSP/plate amps for the bass driver(s). I've used bi-amping for several years but the plate-amps featuring DSP is just simply the way to go for larger speakers. It allows rock solid and deeper bass from smaller speakers - and it allows people to adjust bass level to fit their often less than ideal room acoustics. So much needed! I haven't made any statistics, but I think there were more constructions this year in Munich featuring plate amps for the bass drivers than last year. I'm sure it will catch on and be standard for larger speakers in the future. Hypex is launching a wider range of DSP/plate-amps, Fusion, later this year and I'm looking forward to learn their new products.
Our attic has been stuffed with speakers, and a few weeks ago I launched
a
summer sale to make room for new constructions.
Fortunately three set of speakers have already been sold. The
Illuminator-4 is still available and it will probably take a bit longer
as it is not exactly cheap. I really hate to let go of this speaker.
It's a darn good speaker and the best woodwork I've ever made. Hopefully
it will find a room somewhere delivering what it is capable of. It
deserves the best equipment you can buy.
Buying stuff is usually a matter of a few clicks. Selling stuff takes
time, a lot of time! Typically 20-40 mails back and forth before a deal
is final, money transfer and thorough packing to ensure safe arrival.
15th April 2017
It's been a long wait for the SBAcoustics Beryllium domes - and it was
worth the wait. Standard testing can be found
here. Implementing these domes in three of my SBA constructions was
easier than anticipated, as frequency response and sensitivity is so
much alike the TW29RN tweeter that no changes to the crossovers were
needed.
Updates can be found here:
SBAcoustics SBA-10 with Be dome, TW29BN
SBA MW16 MTM with Be dome, TW29BN
SBA
MW19 with Be-dome, TW29BN
At around 300 EUR/ea, they should reach a wide audience. Can't believe how good domes we have these days!
25th March 2017
The winter months are the busiest DIY months of the year. The majority
of speaker kit parcels leaving Jantzen Audio goes to the Northern
hemisphere and whenever it's cold, people go to their workshops and -
among other things - build speakers. So, there have been a lot of mails
and diy-service this winter and little time for the new constructions
planned. Apart from restoring Lenco turntables I've done quite some work
on digital amps for the bass section of larger speakers and in
particular programmable digital amps allowing whatever slopes needed for
our bass drivers, and not only this, but also allows us to equalize bass
performance to suit our mostly horrible home acoustics - and horrible
speaker placement not to forget. Most people never get the best of their
investment due to speakers having to be placed up against walls or in
corners.
Hopefully this will result in some new constructions later this year.
Having used
bi-amping for several years I've always wondered why speaker
companies producing larger speakers not more often use bi-amping or
plate amps for their 10-12-15 inch bass drivers and offer a kit where
you simply do not need to buy a 200 watt solid state that not only
deliver the amperes needed but also have a great midrange and treble
performance. We all know how difficult it is to make heavy muscle amps
that can both deliver amperes for the bass and smooth mid-treble
performance. There's no sonic rationale for having a single amp doing it
all. I heard great 200-300 watt amps at the Munich show last year, but
the prices were out of this world. We're talking 20-50 kEUR for a decent
sounding amp like Ypsilon, Nagra and others. 2 x 400 watts can be had
for less than 200 EUR these days and all it takes is a pre-amp with
double output running a workhorse for the bass and your 20-40 watt pet
amp handling mid and treble.
Vandersteen is a manufacturer that cleverly use a plate amp to run the
bass drivers - and also features extensive bass equalisation. Well done!
Why don't Wilson Audio speakers not come with a plate amp taking the
heavy load of running the bass drivers in their larger systems? Plane
silly to my mind, but marketing always wins and the customer is always
right.
I guess it's a conceptual thing. Apparently the audience for such
speakers do not see their system that way, rather two speakers with
passive crossovers and two serious mono-blocks running it all. High-end
is also show-off and conservative in appearance.
Any thoughts on this and you're welcome to report.
I obviously follow the launch of new speaker drivers from my preferred
range of manufacturers - and sponsors. What I've noticed is quite a
range of midrange drivers with 4 Ohms impedance. Why 4 Ohms? We can't
use these midrange drivers without applying serious attenuation. What we
need is 8 and 16 Ohms midrange drivers as long as you guys don't produce
bass drivers that allows us to make speakers with an overall system
sensitivity above 87-90 dB. I know, I know! If you target 90+ dB
sensitivity we're talking 80-120 litre cabs and few people build
speakers that size.
I'm currently doing a crossover for a 3-way with a 4 Ohm bass driver
allowing a system sensitivity around 88 dB and still I would need a 16
Ohm midrange driver if I was to avoid attenuation resistors. But nope! 4
Ohms is what we have if we want a midrange driver. Has to be said
ScanSpeak does make 4"/8 Ohm midrange drivers, but what about 5" and 6"?
All of my 3-4 way systems use attenuation resistors for the 6"/8 Ohms
midrange drivers. I'm afraid marketing wins again, because if they
did make 16 Ohm midrange drivers, nobody would probably buy them
being afraid of running out of sensitivity.
13th December 2016
This Autumn/Winter has been busy on client work and some projects have been postponed, but this SBA MTM should emerge some time in January 2017. As mentioned in the SBA-10 construction file I initially set up a small 2-way from MW16 and TW29 and was surprised from what I heard. So how about two MW16 and we have some 238 cm^2 membrane area, more than most 8" drivers. Initial simulation suggests a very simple crossover. Cabinet will be easy, a skinny rectangular box that should be easy for most diy'ers having a handheld saw and a router. I only used tape and a few clamps for gluing cabinets, so very few tools needed.
To reduce my stock drivers, I made the above 3-Way Classic kits for sale
incl. front panels and ready made crossovers. I made three kits, all sold
by now, with premium components, HDF front panels and Superior-Z in
critical places of the crossover. Wires, terminals, ports, all ready for
mounting.
I recently went to a client from last winter to fine-tune/check his
gigantic 4-way system. These are not speakers you bring in the trunk of
your car to my workshop! 18" bass driver, 12" midrange and horns for the
rest. 115 kgs/ea. Active crossover at 200 Hz and the rest is passive. I
brought my laptop and DAC and finally heard a few tracks as they
should sound. With a system sensitivity of 100 dB/2.8V the dynamics
are scary! These speakers can cause tinnitus you'll have to live with
for the rest of your life!
There are very good reasons I don't go this route myself, as I simply
don't have room for such giants. And as always with horns there are
things that finally sounds right, but there also things where horns have
their very special way of dividing your record collection in good and bad.
I guess it's time to wish you all some happy holidays ahead. Thanks for all mails and suggestions coming in this year. It's been an exiting year and should I point to some highlights it will be the SBA-10, Illuminator-4 and not least the Munich exhibition i May. Go there and find out how different we think reproduced music should sound, from tiny 3" drivers to gigantic horns. It's a treat and Munich can be really nice in May.
November 2016
It has been busy times and a new Up-Grade filter for the vintage B&W 802 s3 has been launched. Click image above to go to page. Next in line is an Up-Grade kit for the successor of JBL-L100, the L112. Click images to go to websites.
To the right a new speaker, the SBA MW19. This features the SBAcoustics MW19-8 driver, which is large 7" driver and delivers a credible bass from only 20 litres and one of the most transparent midrange I've ever done. Having such a large driver requires a good tweeter that can handle a low point of crossover and like the SBA-10, I use the SBA TW29RN-B, which has become one of my favorite tweeters. In reality a ring-radiator due to the fixation of the membrane at the center. This speaker features a healthy 8 Ohm impedance, minimum 6 Ohms, and my GlowMaster tube amp loves it. The SBA MW19 was perceived as a studio monitor, but is equally suited for domestic use. Highly recommended if you want a big small speaker.
Sept 2016
Click image to go to website
Pleased to present my first construction dedicated for corner/near-wall
placement. Based on the fact that most people have to place speakers
near walls or close to corners due to simple lack of space or spouse
having specific ideas on living room decor. And also based on the fact
that most people enjoy music while doing other things, they hear
music while others (few) listen to music (audiophiles). Now,
I'm also sure the latter group do not necessarily enjoy
music more than the former group. Quality is highly subjective.
Setting up these speakers in various rooms in our house was a rewarding
exercise in how the rooms played their different roles in shaping the
overall sound. Moving the speakers a little back and forward with regard
to front wall and side walls impacts the sound and experimentation is
imperative in getting the sound you like the best.
Making the cabinets was fun. They are so easy to make, just like the
very first speakers I made in the Seventies. What I couldn't do back
then was making a very simple series crossover, delivering a flat
response with point of crossover exactly where I wanted it. Only really
good drivers and proper measuring gear and simulation software can
create such results from so little. Only 4 (four) components in the
crossover.
We're into the Autumn months now and during the summer months I have
made plans for the rest of the year and probably into 2017. Six speaker
projects where preliminary modeling suggests interesting 2-to 3-way
speakers for smaller systems. No big speakers in pipeline. Two of the
projects are mkII versions of former constructions, an Ekta mkII and a
NOMEX-164 mkII also. The reason for these mkII version is that I think I
can do better today than 10+ years ago.
Two SBAcoustic speakers are in pipeline, a d'Appolito from MW16 and and
small two-way for studio monitoring from the MW19 driver. Obviously a
"Studio Monitor" can be used domestically like any other speaker.
There's nothing special about a studio monitor unless a manufacturer
make a black cabinet and claims it for studio monitoring.
So, stay tuned - and please do NOT ask when they will be ready or any
other detail. Thanks!
August 2016
It's summertime and time for house maintenance and fighting vegetable
garden weeds. It's time for harvesting greenhouse cucumbers and
tomatoes. The taste is unbelievable! It's time for bicycle rides and
beech picnics and all the things we enjoy about summer here high up on
the Northern hemisphere. The sun goes down a quarter to ten in the
evening.
It's also time to make plans for Autumn and winter months and there are
lots of plans, which I shan't reveal now. May and June spare time was
spent making the upper cabs for an Illuminator-4. I set up a tweeter
panel for the 7100 tweeter and made the Ill-4 crossover - and I'd
forgotten why I had the Ill-4 running for three months before engaging
in the Ill-5 construction.
This construction dates back more than a year and went before the
Illuminator-5 but I got caught up on making the ultimate ScanSpeak and
left the Ill-4 for later. It takes time to make the upper cabs but I'm
pleased with the result. Just waiting for the final crossover components
and it'll be ready for launch.
Understandably few engage in Ill-5, although a few kits have been sold,
due to cost and cabinet complexity. The Ill-4 i more manageable and cabs
can be made very simple if the above doesn't match your workshop tools.
It takes a good table saw to make the above, but as you will see later,
it can be made very simple as long as front panel dimensions are kept.
I dare say it belongs to the three best speakers I've ever made.
SBAcoustics
If the Illuminator-4 is above your budget you may take a look at the SBA-10. It's been in my living room for three months not and I don't even miss my ATS-4 reference speakers. For the price it's unbeatable and the only thing that makes a (very little) difference to the ATS-4 and Illuminator-4 is the dedicated 8" upper-bass driver. The SBA-10 even goes a bit deeper and the Satori tweeter for sure puts a question mark to the use of beryllium domes, that's how good it is. Working down to 1.5 kHz it handles all of the treble range - and it pays off. Pays off big time! One thing I was pleased to hear from visitors was how small it is. This was my intention with the cabinet design. It's a potent 10+6+1 speaker and level 2 is 2200 EUR! Frankly, you have to spend serious money on any commercial design to match the performance of this speaker.
Finally I have some 10" high-efficiency drivers suitable for 3-ways for sale. Check my sales page: http://www.troelsgravesen.dk/sale.htm
May 2016
Guess it's been a while since last update. The cabinets for the
SBA61-NAC gave the opportunity to launch three monitors with different
flavours due to cone materials and crossovers. Click images above to go
to websites.
My keeper is the SBA61-NAC, maybe because it the first I made - and
maybe because I want to play it to visitors who may have some prejudice
against alu cone drivers. I really like the sound of this speaker.
There are now four different 3-Way Classics with the addition of the
SBAcoustics version. The SEAS, ScanSpeak and SBAcoustics are all in the
same price range where the AudioTechnology is for the tasty
cost-no-object audience. The AT does has something to offer the others
do not - but it comes at a price.
I've had samples of all SBAcoustics Satori drivers and if successful,
there will be a relatively compact 3-way from 10+6+1. Probably a couple
of months from now.
The Satori tweeter has been tested and added to the two others, click
here.
January 2016
Download the history of Danish Loudspeakers
Click image to download paper (98 MB)
28 December 2015
Thanks to all for reporting back on your constructions in 2015! Always exciting to see ones work in the hands of others.
Christmas holidays have been busy and some updates on AudioTechnology 3WC and Illuminator-5 featuring the SS D3004/604010 Be dome have been launched. This was really quite easy as I only needed to adjust tweeter attenuation and didn't have to make basic changes to the crossover. Only the mini Discovery 12W took a whole new tweeter section - and I'm not expecting many builders here, but should you want the best from a mini, it's worth while.
Tests on two SBAcoustics tweeters have been launched here. In particular the 1" alu dome has impressed me by exceptional low distortion.
The subwoofers have been finished and will be reported soon. Perfect partners for AT-3WC as seen on photo below.
Currently a 3-Way Classic from SBA drivers is under construction. To be launched in January.
Happy New Year!
13 November 2015
It's been quite a while since last posting. The OBL-15s have been on the agenda and also some rather complicated client work including compression drivers and horn-loaded tweeters. Compression drivers are tricky and need careful time-alignment to make crossovers work properly. Whenever I needed a break, I would blow my brains out with the OBLs seen below. These can make whatever can rattle in my workshop - rattle!
22-11-2015: Now launched here.
I'm waiting for crossover components to make the final boards and it shouldn't be long before launch. Please do not ask for details before launch. Thanks.
Next I've had some 26W/4558T00 subwoofers from ScanSpeak and I hope to launch my experiences before the Christmas holidays. Not that there will be any news here as the 26W drivers and the Hypex 4.0 plate amps have been reported elsewhere, but I want to report some experiences from mating the subs with my Discovery 12W, my Ellam 98 mkII and the AudioTechnology 3WC to pick a range of speakers from being very small to what I see as middle-sized (AT-3WC). Subs don't make a pair of shoe-box speakers big but for some the very low-end oommph is enough.
I've had a pair of the new ScanSpeak Be domes, the D3004/604010, and have reported here. I'm looking forward to make versions of the Illuminator-5 and the AudioTechnology 3WC with these domes. And why not the Discovery 12W as already done? The ultimate mini.
Last, but not least, Director of Sales and Marketing, Bo Albrectsen, SB Acoustics, paid me a visit to hear my stock speakers - and offered sponsorship of their drivers. I couldn't be more pleased. I've done a few SB Acoustic drivers for clients and I'm looking forward to try out their products in 2016. Below a selection of drivers I picked for 2-3 constructions. Primary target is a classic 3-Way, an "8+4+1". Normally I would be hesitant to dig into alu cone drivers. I did some NNNN alu cone drivers 10+ years ago and they were horrible, but the 6" here from SBA looked very promising from specs. Initial testing looks promising too and this driver may very well find its way into future constructions. The 1" alu tweeter has been tested and will be reported soon (read here). Exceptionally low distortion all the way down to 1 kHz and exceptional dispersion too. Really impressive.
06 September 2015
As discussed on the
Illuminator-5
pages, drivers' dispersion characteristics has been on my mind lately as
it has such an immense impact on perceived sound. We may have a 2-way
(6" + 1") and a 3-way (e.g. 6" + 3" + 1") and they may have exactly the
same frequency response and they may very well have identical horizontal
dispersion and yet sound like night and day. There are many reasons for
this being partly the intrinsic dispersion characteristic of the
drivers, the crossover topology and drivers' overlap. The latter I find
interesting as a 6" like the ScanSpeak 18WU, having a rather large and
deep cone, soon starts beaming toward higher frequences (Beaming: Put
your hand around your mouth like a conical horn and say something.
You'll notice the change in sound as you prevent horizontal dispersion.
This is what drivers do when we reach a frequency having a wavelength
equal to the diameter of the cone).
The 18WU has a 14 cm cone diameter equal to 2457 Hz (34400/14). Above
this frequency the driver will loose dispersion (as can be seen from
data sheet). Already at 2000 Hz we have reduced response at 30
degree off-axis. Right! We place our point of crossover 2 kHz and we're
safe. Not exactly, because depending on the slope of our crossover we
may still have an "echo" of this "beaming" present in our perceived
sound. The more shallow our slopes, the more reminiscens of "beaming".
Cone shape and material plays its role too. Some 6" drivers have a
fairly shallow cone and proper designed dust cap and may be less prone
to beaming. The very old version of the Vifa C17WH had a very shallow
cone and a wide dust cap and had a wonderful midrange projection with
little tendency of beaming. Using soft paper cones may have reduced the
problem even more as not all parts of the cone would produce high
frequences. With modern hard cones we like to reduce cone break-up and
all parts of the cone should do all frequences. Very well, the price to
pay is increased beaming and some take point of crossover down to 1.5
kHz from 4th order crossovers to make a 2-way from "6+1". This takes
very good tweeters as most 1" domes start producing significant levels
of distortion around 1 kHz. Many of the ScanSpeak tweeter are safe with
a 4th order crossover at 1.5 kHz.
OK, then we make a 4th or 6th order filters to prevent this and yes it
works, but adds to overall complexity and cost - and maybe not the sound
we were looking for. Getting 2, 3, 4 or even 5 drivers to make a
coherent sound is so full of compromises that there is no right, only
clever choices and preference. One reader called my current preference
for LR2 filters my "comfort zone" and requested more diversity. Well, he
may be right, but the last ten years of speaker building has proved the
LR2 - to me - a good compromise between cost/complexity and performance
and I'll stick to this until I find something better.
Click image to go to AudioTechnology 3-Way
Classic
Above my most recent construction, a powerful 3-way from AudioTechnology
drivers and the superb ScanSpeak R3004/602010 tweeter. I've really come
to love these small tweeters, R3004/602010 (R for ring-radiator) and
D3004/602010 (D for conventional dome). The 15H52-0613-SDKAM midrange
has a tremendous midrange projection and the level of transparency
equals any fancy new cone material like ceramics, composite
carbon-whatever, Rohacel, etc. This midrange driver spews music into the
room and I never thought I'd say you can place this speaker up against a
wall and not get that usual "closed-in" sound from boosting the bass due
to room-gain leaving the midrange distant and with lack of detail. The
15H52 will still help making a credible soundstage. Now, don't get too
exited, the speaker will still sound better being on stands out on the
floor.
The AT-3WC proves a dynamic headroom above any other speakers I've made
of this size and should you want the 20-40 Hz range also, add a decent
subwoofer. You don't get it all from 2 cubic feet.
08 July 2015
The summer holidays are ahead and with the speaker shown below, I very much feel like taking a few weeks off. This has been the longest project ever, not least due to the woodwork.
Click image to go to website
Cost-efficiency, contrary to the Discovery-4, has not been an issue
here. All the best ScanSpeak can produce is going into this 5-way
speaker. Besides a potent bass system, the primary aim here is to do
something about dispersion in upper-mid/lower treble. Thus, the 12MU has
entered the system, providing a dispersion and a presence quality the
usual "6+1" rarely manage, unless special drivers and low point of
crossover is used.
Enjoy your holidays!
01 May 2015
Buying is easy! A couple of clicks and you have made your purchase.
Selling takes ages! I'm having a
sale of
some of the stuff accumulated over the last ten years. I didn't realise
I had that much surplus hifi on the shelves!
Selling takes time and sometimes provides you an unexpected insight into
how people handle their finances. "I want to buy...", sometimes means "I
would like to buy if I had the money, but fact is I don't...".
Some of my surplus components went into the the design above, the Revelator 4R, featuring the more sensitive, un-coated and more lively version of the ScanSpeak 5" Revelator bass drivers. Click image to go to page. I've had a few requests on this driver and here it is. For tweeter I picked the R2604/832000.
27th March 2015
With the two center speakers above I hope to fill a gap in the portfolio
of floor-standers suitable for surround sound. The Prestige version can
be build for a modest investment, where the Excel version will take you
a little further in sound quality. Key parametre for center speakers is
even horizontal dispersion, thus is must be 3-ways and 4th order LR
between mid and tweeter.
Click images above and go to page of CENTER-641!
Click images to go to website
This micro from Discovery W12/8524G00 and R3004/602010 is meant to be
used for desktop application and where space is seriously limited. And
why not make your kids get used to good sound from an e.g.
NAD 3020D amp, being fed from a laptop or other digital sources? The
DISC-12W may be a way to better sound culture.
There
are, and have been, many excellent 4" drivers and I clearly recall the Vifa PL11 range of drivers as some of the best at that time.
Fortunately ScanSpeak has some excellent 4" drivers and here I picked
the 8 Ohms version from the Discovery series. To supplement this
excellent wide-range driver I use the R3004/602010, which basically
is the same as the costlier R3004/662000 but in a smaller package
suitable for limited space. Click
here.
7th Februar 2015
Click image to go to page.
Finding second hand 50 EUR old Lenco turntable has become a hobby and
the dark winter evenings are fine for doing some restoration work. These
two above are the 3rd and 4th and I have two more in store, both L75s. I
found an L78 on eBay at reasonably price and wanted to see how it may
differ from the L75. The basics are the same, only the arrangement
around on-off button and the brake function is different. I'd still
recommend the L75 if you have the choice as it is simpler to renovate.
My second L75 was made for a client, here seen above with a Moerch DP 8
Precision tonearm. Having both a 9" and 12" Moerch tonearm it's obvious
to make comparison and I'm afraid the 12" is more of a theoretical
advantage over the 9". Are we really able to the hear the slightly
increased tracking error from a 9"? Time will tell when I make a more
systematic comparison of the two arms with the same cartridge.
You may ask why I need two turntables - and I don't. I just love
restoring these 45 year old decks. It's relaxing and highly satisfying
when set it up and start listening records.
Click image to go to website.
I had hoped to launch a bigger 3½-way system in December but two months
of work on the crossover just left me more and more frustrated with the
treble performance, hence the project was ditched. Sometimes we just
have to give in and start all over. Well, the bass drivers stayed the
same, only this time I used the ScanSpeak 18W/8535-01 for mid and the
R2604/833000 for treble. One afternoon of work and the crossover was
done! The mid and tweeter appeared to be a match in heaven. The rest was
fine-tuning and the overall voicing of the speaker. The bass drivers are
from the ScanSpeak Discovery series, 8" and 10". Basically it's an
ATS4 from modest
priced drivers, except for the midrange drivers, the most important of
them all.
What's seen above is meant to be a seriously large speaker from a very
modest investment. All drivers alone are 790 EUR. What I've tried is to
spend the money where it counts: The midrange driver and the crossover
components' quality. I haven't experienced any driver that
didn't benefit from good quality crossover components.
The cabinet is designed to be as easy as possible and something for any
diy enthusiast with a little experience in wood working.
Speaker construction launched. Follow link
here.
13th December 2014
Above the
Ellam Disc 15 and
DTQWT-mkIII,
the latter at the photoshoot. This was the finale for 2014. Eight new
speakers and two updates,
8008-Center,
QUATTRO mkII. I
had hoped to launch the new ScanSpeak 12WU mini/Be dome, but it seems it
will have to wait for the new year.
Mails are pooring in this November/December, certainly the time of the
year where speaker building speeds up to culminate in January/February.
Looking back there seems to be a trend towards either very cheap
constructions or very expensive constructions. The ATS4 and NEXT4 have
created much more attention than anticipated and the number of people
currently engaged in constructing the ATS4 was unexpected. What also has
appeared are quite some newcomers, and also some people that may have
trouble finishing the projects, either due to lack of experience in
woodworking or simple soldering of the crossovers. But there's a
beginning for everyone and I strongly advise not to start up on some of
the more complicated constructions. Speaker building can be addictive
and once succeeded, there may be more to come.
What appears to never end is the perception that a crossover is a
crossover and that front panels can be made to personal taste and
skills. The number of times I copied in this link is uncountable:
http://www.troelsgravesen.dk/crossovers.htm
The link tells that if you want to make any of the constructions here,
you must follow front panel design and drivers' placement, otherwise
you'll need a new crossover and I cannot help without having your
speaker in by lab. What's behind the front panel is not without
importance, but here there is room for creativity. The stepped baffles
are there for a reason (better sound) and you cannot mount the drivers
on a flat baffle without a new crossover.
The page also tells that whatever drivers you have on the shelf, I cannot make
you a crossover because crossovers cannot be calculated and they cannot
be made from manufacturers' data sheet.
Every driver's response is dependent on the baffle on which is is placed
and the crossover must be constructed accordingly.
Thanks for all the response over the last year. Feel sure that everytime
a question to one of my constructions appear, I consider updates with
further information and details and suggestions. Keeping the website
alive is done every single day.
I wish you all some relaxing holidays ahead - and happy workshop
hours!
Thanks to my
three sponsors for providing the drivers and crossover parts needed.
Without their help and support things would have looked very
differently.
Just had these babies in for 2015 projects.
Preliminary measurements suggest equal performance to large-faceplate
brothers.
These tweeters allows very close to midbass placement and reduced
crossover lobing. Time will tell.
October 2014
Launching a new high-effiency driver is a daunting task and it's taken
almost a year before the first production batch reached Jantzen Audio.
In particular the edge coating took time; the right glue, the right
amount, the right place, etc.
It goes without saying a new driver must be better than the old one. The
aim of launching a new driver was low-loss. A new voice coil former
combined with the phase plug increased Qm from 1.7 to 10! Low-loss mean
better dynamics and that micro details are not getting lost in
mechanical and electrical damping. Click image below to go full details.
The new 8008-HMQ driver is not compatible with the old JA8008, thus new TQWT and DTQWT crossovers are in prepartion and will be released this November.
Click image to go to page
click image to go to page
Restoring an old turntable, making the plinth and setting up a new arm is at least as much fun as mounting new cabinets with drivers for the next speaker. Click image above and read why I love turntables and vinyls.
Three new speakers are finished and one already launched, the Ellam-98 mkII. The other two speakers are waiting for the main speaker driver to be released from the factory. One is the 12WU fra ScanSpeak mentioned in the June 2014 speaker-talk. I hope the 12 WU will soon be ready. The third speaker...time will tell.
The Ellam 98 mkII is one I've wanted to do for a long time as I think
the 9800 dome deserves much more attention. It's been around for many
years and I don't think any alu dome has been made that does it better
than this one. To my ears it does as well as the Accuton C30 ceramic
dome.
Making a stepped baffle allows true time- and phase-coherent LR2 filter
to be implemented, a key design feature that justifies an mkII version.
Besides this, it's an easy speaker in terms of woodwork.
August 2014
After the ScanSpeak Discovery Classic 3-Way, I just had to do an upgrade of the popular SEAS 3-Way Classic, thus the SEAS 3-Way Classic mkII, delivering increased sensitivity and a better and simpler crossover from retracting the tweeter some 20 mm. This allows implementation of a true LR2 filter and adds smoothness to the treble performance and mid-tweeter integration.
The two contenders above
Please do not ask which one is the best. Thanks! And enjoy!
The last three of months have been busy. Two speakers from ScanSpeak drivers. A capable 3-way from Discovery drivers delivering an awful lot of good sound for a very modest price tag - and the other a very small and rather expensive mini-monitor from new drivers not even ready for release yet. The ScanSpeak Classic 3-Way has been on the to-do list for a very long time and the Discovery drivers were not even developed at the time as my initial thinking was around the Classic series of 22W/13M/1" dome. However, these affordable drivers deliver quality we didn't dream about some 20 years ago. Better voice coils, more linear response, etc. The level of transparency these Discovery can deliver is quite remarkable and it's all up to low-loss suspensions and rigid cone materials with modest - and ear-friendly - break-up modes. The ScanSpeak 3-Way Classic will be launched soon. The mini features all-new drivers, a 12WU-something (final name not decided yet) and the small-size beryllium dome, D3004/604050 (not on the ScanSpeak website yet). The speaker was developed for the ScanSpeak exhibition at High-End Munich 2014. If you need cost-no-object minis for your laptop system - or smaller rooms - this might be an option. The 12WU is made from a combination of PP and alu cut up in the pattern of the Illuminator cones and glued together again, delivering extended linear response and the best sound I've ever heard from a 4". The Be dome, well, does what we expect from such a construction. A stepped baffle allows LR2 filter and transparency is exceptional. The 12WU features 2.5 litre volume and it was quite a challenge to fit in ports and crossover in such small volume as can be seen below.
12WU crossover mounted on rear panel.
Music last, but not least, a lot of time has been spent installing a new tonearm on my Lenco L75 turntable and getting to know proper set-up better by doing actual measurements. A protractor has been acquired and the Adjust+ software from Feickert Analogue is currently being tested. An article on why I listen to vinyl rather than digital is in preparation.