Simon, one thing I have noticed with the OB's I've been building is that the bigger drivers sound better.
Some of the best sounding mid-rangers have been 8inch full range drivers, and these are avaliable cheap on E*** and trading, heck I just bought a pair today $5.50 for 2 BNIB and a third thrown in for good measure and testing purposes.
Also keep in mind Fostex/Foster ( not to neglect Tandy/RadioShack ) vintage drivers sound great in this application.
Some of the best sounding mid-rangers have been 8inch full range drivers, and these are avaliable cheap on E*** and trading, heck I just bought a pair today $5.50 for 2 BNIB and a third thrown in for good measure and testing purposes.
Also keep in mind Fostex/Foster ( not to neglect Tandy/RadioShack ) vintage drivers sound great in this application.
Looking at the speaker Pano linked to on Lampizator's site how would it be if instead of the open backed box on the woofer, the top and bottom plates were kept and then heavy quilting ( thin fabric over rockwool, baf or fibreglass) was used for the sides of the open box and even across the back. Would this reduce resonances set up in the open backed box?
jamikl
jamikl
Whatever amplifiers are considered it is their driving impedance which has the greatest impact upon reproduction, and thus a LS optimised for a non-NFB balanced triode will not be best for say AB1 push-pull with NFB or typical SS. SS types can vary too.
The most accurate reproduction within any bandwidth does not automatically sound best, and vice-versa.
The most accurate reproduction within any bandwidth does not automatically sound best, and vice-versa.
large drivers
Do not be hung up on large excursion. 1.5 mm can be very good for midrange.
The less excursion, the less distortion. Think 8" for midrange. The alnico is also
a good suggestion, although I have used the Moth Cicada driver with great success. Super flat response is more critical if you are listening at high levels.
For lower levels, you may find that a rising response sounds better than
the muddling of a bunch of filters, even simple filters. Flat respose has become
a cornerstone of speaker design, but will never ensure a good sounding speaker.
If using an H or U frame, by all means damp the inner walls with felt or old
wool sweaters. You will hear the difference.
I can recommend MJ King's project with the 15" alpha the Fostex fe103.. These
measured very flat within the room. Bass down to 60 hz. ensured easy
integration with a sealed sub. (of course two subs would have been better).
This setup was made for SS equipment. I drove them with a little 12 watt tube
job, and although this was not quite enough power, I did enjoy the sound .
The bass was not controlled well enough for my taste however. I biamped
using the separate passive filter for each driver
with SS on the bottom and tubes on the top and this was better. It was wonderful
to be able to control the amount of bass from the listening seat with
the remote control vol. for the woofer's amplifier. This is a great advantage
of crossing over in the 300 hz. region.
Another problem for me with this very inexpensive design was that
there was so much distance between the drivers.
Think about .7 to .8 qts for SS amplification. You could just buy a Tonian Labs
Phy setup or some nice Alons and be done with it.
Best to you. you are on the right track and i don't think you will ever go
back. The little back loaded horns are tempting for a small listening area,
but I can not get used to the delay of the back wave in the bass.
Do not be hung up on large excursion. 1.5 mm can be very good for midrange.
The less excursion, the less distortion. Think 8" for midrange. The alnico is also
a good suggestion, although I have used the Moth Cicada driver with great success. Super flat response is more critical if you are listening at high levels.
For lower levels, you may find that a rising response sounds better than
the muddling of a bunch of filters, even simple filters. Flat respose has become
a cornerstone of speaker design, but will never ensure a good sounding speaker.
If using an H or U frame, by all means damp the inner walls with felt or old
wool sweaters. You will hear the difference.
I can recommend MJ King's project with the 15" alpha the Fostex fe103.. These
measured very flat within the room. Bass down to 60 hz. ensured easy
integration with a sealed sub. (of course two subs would have been better).
This setup was made for SS equipment. I drove them with a little 12 watt tube
job, and although this was not quite enough power, I did enjoy the sound .
The bass was not controlled well enough for my taste however. I biamped
using the separate passive filter for each driver
with SS on the bottom and tubes on the top and this was better. It was wonderful
to be able to control the amount of bass from the listening seat with
the remote control vol. for the woofer's amplifier. This is a great advantage
of crossing over in the 300 hz. region.
Another problem for me with this very inexpensive design was that
there was so much distance between the drivers.
Think about .7 to .8 qts for SS amplification. You could just buy a Tonian Labs
Phy setup or some nice Alons and be done with it.
Best to you. you are on the right track and i don't think you will ever go
back. The little back loaded horns are tempting for a small listening area,
but I can not get used to the delay of the back wave in the bass.
Wow, what a load of fantastically helpful replies! Thanks everyone, there's a lot of info building up here that could put me onto several good paths.
I think I need to focus the search a little and share with you some unfortunate design constraints.
I am listening in a bedroom in my parents' house, for now, so have a small space and hardly any room for speakers.
Max baffle width is, sadly, about 13-14". I don't think I can squeeze 15" drivers in - 12" max. 2 x 12" for bass + 4" - 12" mid would be fine of course.
I will probably never use valve amps or unfiltered full range paper cones as what I've heard sounded coloured and peaky and made my ears want to close a bit. I'm also scared of the voltage. Other aspects of the sound were great but I might be better suited to larger drivers and/or modern, flatter drivers like the CSS FR125 (will hear a set in an OB tomorrow).
The Saba drivers used by the Lampizator chap look intriguing and affordable, but Google isn't pulling much up, so I'm not sure where to buy them.
Xmax - I was only considering this in relation to bass, where it's surely pretty important on a 12" OB woofer.
2 way (FR + woofer) is preferable to 3 way because it's easier to design and it seems like it should sound better too. After various speakers I'm starting to become less interested in it being "impressive" and more interested in simple enjoyment, being drawn in. Example - I had a bit of a shock when my heavily modified CD63 was off for repair and I actually LOVED my old Ebay'd Philips CD650 (TDA1541 DAC) in spite of very poor detail levels.... it just sucked me into the music. Something for another thread.
Midrange - I like this idea of a cheap 8"+ PA driver, but of course I'd then need a tweeter too.
There's a lot of positive stuff here about the 4.5" CSS FR so I'm increasingly anxious to hear it in action. It's seriously good value from Vikash on here's website: http://www.madaboutsound.com/prod_det.asp?cid=132&sa=cf&ctid=5 - it even comes with T-nuts!
It would be neat to partner this with a 12" or 2 x 12" PA woofers. It's a real shame I can't fit the eminence Alpha 15s in.... I'm looking and there simply isn't enough width in the room!!!!
My current setup with 4 x 7" woofers does very nicely for bass so I could, as a next step, try a new FR driver or mid/top with these. Graham's transformer-bass boost enables usable output into the 40s - which is superb for this room!
Simon
I think I need to focus the search a little and share with you some unfortunate design constraints.
I am listening in a bedroom in my parents' house, for now, so have a small space and hardly any room for speakers.
Max baffle width is, sadly, about 13-14". I don't think I can squeeze 15" drivers in - 12" max. 2 x 12" for bass + 4" - 12" mid would be fine of course.
I will probably never use valve amps or unfiltered full range paper cones as what I've heard sounded coloured and peaky and made my ears want to close a bit. I'm also scared of the voltage. Other aspects of the sound were great but I might be better suited to larger drivers and/or modern, flatter drivers like the CSS FR125 (will hear a set in an OB tomorrow).
The Saba drivers used by the Lampizator chap look intriguing and affordable, but Google isn't pulling much up, so I'm not sure where to buy them.
Xmax - I was only considering this in relation to bass, where it's surely pretty important on a 12" OB woofer.
2 way (FR + woofer) is preferable to 3 way because it's easier to design and it seems like it should sound better too. After various speakers I'm starting to become less interested in it being "impressive" and more interested in simple enjoyment, being drawn in. Example - I had a bit of a shock when my heavily modified CD63 was off for repair and I actually LOVED my old Ebay'd Philips CD650 (TDA1541 DAC) in spite of very poor detail levels.... it just sucked me into the music. Something for another thread.
Midrange - I like this idea of a cheap 8"+ PA driver, but of course I'd then need a tweeter too.
There's a lot of positive stuff here about the 4.5" CSS FR so I'm increasingly anxious to hear it in action. It's seriously good value from Vikash on here's website: http://www.madaboutsound.com/prod_det.asp?cid=132&sa=cf&ctid=5 - it even comes with T-nuts!
It would be neat to partner this with a 12" or 2 x 12" PA woofers. It's a real shame I can't fit the eminence Alpha 15s in.... I'm looking and there simply isn't enough width in the room!!!!
My current setup with 4 x 7" woofers does very nicely for bass so I could, as a next step, try a new FR driver or mid/top with these. Graham's transformer-bass boost enables usable output into the 40s - which is superb for this room!
Simon
SimontY said:
There you go, Simon - Bob's your Uncle!
There are a lot of fun and inexpensive full range drivers out there that can do top end duty - even if you do need a tweeter.
Following Mr. Lamizator's lead, I tried a pair of vintage 8" Danish drivers and Grundig cone tweeters on top of my OB 15's. I really liked the sound. A big change from my prevoius FR8s.
If your 4x7 is making you happy, you should be able to pop in a lot of different fullrange drivers, either large or small - and have some fun. It's going to be the crossover that wants adjusting.
I just put together a pair of the Manzanita rigs yesterday and love them. I'm using a different tweeter, the big Scan Speak 3806. But I plan to try a few small full range drivers in place of the SS3806. It's easy to do.
Whatever happens, have fun!
Attachments
I heard the CSS today and thought they sounded a bit shut in with no presence in the vocals. They did sound accomplished in a smooth, quiet, polite way, but very recessed! Perhaps they're more suited to midrange use than anything more, or perhaps those speakers I heard them in have problems in the implementation. The treble was of a high quality but a bit quiet for my liking.
Here's another interesting mid driver:
http://www.madaboutsound.com/prod_det.asp?cid=136&sa=cf&ctid=5
And this one from Markaudio has a response that might sound more "interesting" than the CSS:
http://www.madaboutsound.com/prod_det.asp?cid=143&sa=cf&ctid=5
Simon
Here's another interesting mid driver:
http://www.madaboutsound.com/prod_det.asp?cid=136&sa=cf&ctid=5
And this one from Markaudio has a response that might sound more "interesting" than the CSS:
http://www.madaboutsound.com/prod_det.asp?cid=143&sa=cf&ctid=5
Simon
SimontY said:
Hi Simon,
i guessed that you would come to this conclusion.
It coincides with my impression when using a single
FR 125 S without equalisation ...
But IMO the unobtrusive way they sound is a strength,
which makes it possible to equalise them without using
any rude narrow band filters. Presence to brillance region
has to be emphasized, thats all.
Furthermore the baffle dimensions have to be matched
to the driver. A narrow baffle is preferable, not exceeding
2 x diameter of the cone. This also creates a smooth
angular dispersion with less lobing.
Kind regards
Hi Simon,
I have not heard many drivers, but I have found that those which have the flattest frequency response do so due to aspects of design which simultaneously ruin the mid and high frequency transduction dynamics. A tailored flat responses does not always generate the best reproduction.
So you have ruled out the CSS from your next construction.
My mains are the Visaton B200, and I have no wish to change them (Sd = 200cm^2 and treated cloth surround). However, here in the UK they run approx £100 each from Impact Audio (probably will be more soon the way Gordon Brown is behaving) and I cannot recommend their use without them being modified first; ie. laying out all that cash and still having to cut out the original dust-cap before it becomes tolerable, which also means that you'd never be able to sell them on as 'genuine' secondhand.
Is there anywhere near you where you could hear the B200, modded or not ?
Cheers ........... Graham.
I have not heard many drivers, but I have found that those which have the flattest frequency response do so due to aspects of design which simultaneously ruin the mid and high frequency transduction dynamics. A tailored flat responses does not always generate the best reproduction.
So you have ruled out the CSS from your next construction.
My mains are the Visaton B200, and I have no wish to change them (Sd = 200cm^2 and treated cloth surround). However, here in the UK they run approx £100 each from Impact Audio (probably will be more soon the way Gordon Brown is behaving) and I cannot recommend their use without them being modified first; ie. laying out all that cash and still having to cut out the original dust-cap before it becomes tolerable, which also means that you'd never be able to sell them on as 'genuine' secondhand.
Is there anywhere near you where you could hear the B200, modded or not ?
Cheers ........... Graham.
Thanks for sharing these interesting thoughts guys.
I really wanted to love that CSS but could only respect it and I felt no emotion towards it. A front firing tweeter sounds like a crime but it could be crossed over at something like 6khz and I suspect this would give the presence that is missing.... but would it then lose the homogeneity I am hoping for when using a wide band driver? The CSS could still be allowed to play out the full top octave - just with a "helper". I have not yet ruled out the CSS. The baffle the CSS was on was already very narrow, with the CSS placed right next to the inside edge and top.
I will not be using line-level EQ in this speaker.
The sound of the CSS does push me more towards "lively"/PA, paper mids like the Eminence, and others.
I've heard a lot about this Visaton B200 but gosh, having to cut them up to hear what they can do is a very all-or-nothing situation... and funds are limited. I don't know where I could hear any I'm afraid so that driver might have to wait. I don't think these will quite be the last speakers I ever build though, I don't want to put all my eggs in one basket, as it were!
I know it's hard to give suggestions not knowing my exact tastes but please do keep suggestions rolling in.
Thanks,
Simon
I really wanted to love that CSS but could only respect it and I felt no emotion towards it. A front firing tweeter sounds like a crime but it could be crossed over at something like 6khz and I suspect this would give the presence that is missing.... but would it then lose the homogeneity I am hoping for when using a wide band driver? The CSS could still be allowed to play out the full top octave - just with a "helper". I have not yet ruled out the CSS. The baffle the CSS was on was already very narrow, with the CSS placed right next to the inside edge and top.
I will not be using line-level EQ in this speaker.
The sound of the CSS does push me more towards "lively"/PA, paper mids like the Eminence, and others.
I've heard a lot about this Visaton B200 but gosh, having to cut them up to hear what they can do is a very all-or-nothing situation... and funds are limited. I don't know where I could hear any I'm afraid so that driver might have to wait. I don't think these will quite be the last speakers I ever build though, I don't want to put all my eggs in one basket, as it were!
I know it's hard to give suggestions not knowing my exact tastes but please do keep suggestions rolling in.
Thanks,
Simon
Moondog55 said:
Not yet really, no! I do like the Seas Excel magnesium cones but they're just a bit pricey for me for now.
I'm keeping my eye on Fleabay for Goodmans Axiom 201s, I like these.
Also I liked Lee's (owner of Jamos and CSS on OB) 12" Celestion woofers on OB - lots of grunt and they went deep!
Simon
SimontY said:
You can use two of them in series, bypassing one of them
with an RC and a small capacitor in parallel.
...................................................
--------ccc--- .....adjust brillance.
|.................|..............................
---rrr---ccc--- ....adjust presence
|.................|..............................
---- CSS1 ---------- CSS2-----...
...................................................
But i understand your "non belief in emotional impact"
to a certain extent ...
Kind Regards
Hi Simon,
It is basically the way i do it in my "dipole 08" except for
the fact that "CSS1" in my system is a group of three
FR125 in parallel and CSS2 also ...
CSS1 may also be replaced by a resistor. A voltage
divider may be built up with a second resistor in parallel
to CSS2.
Don't tell the purists about using resistors, but you can
choose well suited types for audio.
I also have some circuitry for LF compensation, which you
hopefully will not need, since you are using a dedicated
woofer. I expect your XO will be far above 100 Hz ?
How will you implement the high pass filter for your fullranger ?
Cheers
It is basically the way i do it in my "dipole 08" except for
the fact that "CSS1" in my system is a group of three
FR125 in parallel and CSS2 also ...
CSS1 may also be replaced by a resistor. A voltage
divider may be built up with a second resistor in parallel
to CSS2.
Don't tell the purists about using resistors, but you can
choose well suited types for audio.
I also have some circuitry for LF compensation, which you
hopefully will not need, since you are using a dedicated
woofer. I expect your XO will be far above 100 Hz ?
How will you implement the high pass filter for your fullranger ?
Cheers
Hi Oliver,
Actually I was just looking at the graphs on your website!
I will indeed use dedicated woofers for the bottom end. I don't know where the XO point will be, but I expect it will be rather low, around 100hz, to smoothly counteract the dipole roll-off. Maybe first order with zobel, maybe steeper...
The high-pass will be passive I'm afraid, so a big horrible electrolytic cap (Mundorf M-lytic probably) and possible coil too.
Simon
Actually I was just looking at the graphs on your website!
I will indeed use dedicated woofers for the bottom end. I don't know where the XO point will be, but I expect it will be rather low, around 100hz, to smoothly counteract the dipole roll-off. Maybe first order with zobel, maybe steeper...
The high-pass will be passive I'm afraid, so a big horrible electrolytic cap (Mundorf M-lytic probably) and possible coil too.
Simon
Hi,
i edited my post above ...
I had good experience in using a passive line
level crossover, circumventing those big caps.
You need separated power amps then for LF and HF.
Maybe the equaliser for the CSS could be integrated
into the Passive Line Level XO, omitting all those passive
components between power amp and speaker ...
Would be a new solution, which i have not seen here
so far...
Cheers
i edited my post above ...
I had good experience in using a passive line
level crossover, circumventing those big caps.
You need separated power amps then for LF and HF.
Maybe the equaliser for the CSS could be integrated
into the Passive Line Level XO, omitting all those passive
components between power amp and speaker ...
Would be a new solution, which i have not seen here
so far...
Cheers
Hi Simon,
some remarks came to my mind:
If you are using a single driver of the FR125 size (4.5")
with a cutoff below 100Hz, the dynamic headroom of your
speaker will be very limited. Even if you choose a 2. Order
highpass.
If you want your speaker to be able to reproduce material
different from "vivaldi as background music for dinner"
you need either a higher cutoff frequency or more displacement
volume.
With XO under 100 Hz displacement volume is essential for
your fullranger especially if you choose a narrow baffle.
IMO you can forget about using a small sized fullranger with
small Xmax, with a XO that low. I know what i am talking about,
since i use 6 of the FR 125 per side ...
A passive line level filter for the subwoofer too would allow
you to compensate for different SPL of (sub)woofer and
fullranger, thereby giving you more flexibility in matching
both due to sonic quality ... instead of having to look after
matching SPL all the time.
The working resistor of the low pass has to be replaced by a
potentiometer then. As long as the woofer has higher
SPL as the fullranger you can adjust your setup easily.
Gives you the opportunity to test and equalise several
fullrangers until you find one that meets your taste ...
you won't get bored for the next years
!
The application of Grahams T-Bass circuit is independent
from that possible decision.
Cheers
some remarks came to my mind:
If you are using a single driver of the FR125 size (4.5")
with a cutoff below 100Hz, the dynamic headroom of your
speaker will be very limited. Even if you choose a 2. Order
highpass.
If you want your speaker to be able to reproduce material
different from "vivaldi as background music for dinner"
you need either a higher cutoff frequency or more displacement
volume.
With XO under 100 Hz displacement volume is essential for
your fullranger especially if you choose a narrow baffle.
IMO you can forget about using a small sized fullranger with
small Xmax, with a XO that low. I know what i am talking about,
since i use 6 of the FR 125 per side ...
A passive line level filter for the subwoofer too would allow
you to compensate for different SPL of (sub)woofer and
fullranger, thereby giving you more flexibility in matching
both due to sonic quality ... instead of having to look after
matching SPL all the time.
The working resistor of the low pass has to be replaced by a
potentiometer then. As long as the woofer has higher
SPL as the fullranger you can adjust your setup easily.
Gives you the opportunity to test and equalise several
fullrangers until you find one that meets your taste ...
you won't get bored for the next years
!The application of Grahams T-Bass circuit is independent
from that possible decision.
Cheers
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