I'm fairly new to speakers; I want to build a small pair for the bedroom; nothing too big, not to bass heavy. I'm thinking T-Amp driving fullrange 3" drivers (possibly Open Baffle).
I've been doing some googling and found quite a lot of decent looking DIY efforts with a Visatron FRs8 (especially on German sites). But I was really supprised by how cheep they seem to be when i looked them up, Rapid are doing them for £7.31 a pop. Can they actually be any good at that price? anyone used them? anyone used them OB?
I've been doing some googling and found quite a lot of decent looking DIY efforts with a Visatron FRs8 (especially on German sites). But I was really supprised by how cheep they seem to be when i looked them up, Rapid are doing them for £7.31 a pop. Can they actually be any good at that price? anyone used them? anyone used them OB?
Sure, if the curve shown is correct, these are nice little drivers.
You will need more than one to get decent SPL and sensitivity.
If you use the FRS8 then you will only get 82dB + 15dB = 97dB at 1 Meter when
at maximum power (30 watts). The 8M seems to give more sensitivity. Not sure what
the diff is exactly. Keep in mind that you will get NO bass from these.
Qt is NOT spec'd. Not on the website for Rapid or in the pdf linked. This means that
it's impossible to know how to use them properly until you know that and the VAS. OB will have less bass.
Imo 6 on a channel might be very impressive... but again, no bass.
I have not used these particular drivers, nor seen any.
Others may have more experience with this driver, etc...
_-_-bear
EDIT:
Found it online.
The 8m has 2x the magnet (better in this case) and has a Qt 0f 0.49.
The 8 has a Qt of ~1.0
I'd opt for the 8m if possible. That Qt is fairly "magic" and will tend to work in almost any cabinet
you chose to use, vented, sealed, etc...
The Qt of 1.0 is a bit high, but would be the one to chose (probably) for OB... I'd avoid OB unless it was carefully done and tested since you could end up with not much happening below 300Hz, which would not sound good, or you could end up with very wooly fat sound around the resonant freq which is ~100hz. depending on things like baffle size and floor bounce.
The freq resp curves are usually done on IEC baffles, which are large flat baffles of specified size. The key is large area baffles. FYI.
You will need more than one to get decent SPL and sensitivity.
If you use the FRS8 then you will only get 82dB + 15dB = 97dB at 1 Meter when
at maximum power (30 watts). The 8M seems to give more sensitivity. Not sure what
the diff is exactly. Keep in mind that you will get NO bass from these.
Qt is NOT spec'd. Not on the website for Rapid or in the pdf linked. This means that
it's impossible to know how to use them properly until you know that and the VAS. OB will have less bass.
Imo 6 on a channel might be very impressive... but again, no bass.
I have not used these particular drivers, nor seen any.
Others may have more experience with this driver, etc...
_-_-bear
EDIT:
Found it online.
The 8m has 2x the magnet (better in this case) and has a Qt 0f 0.49.
The 8 has a Qt of ~1.0
I'd opt for the 8m if possible. That Qt is fairly "magic" and will tend to work in almost any cabinet
you chose to use, vented, sealed, etc...
The Qt of 1.0 is a bit high, but would be the one to chose (probably) for OB... I'd avoid OB unless it was carefully done and tested since you could end up with not much happening below 300Hz, which would not sound good, or you could end up with very wooly fat sound around the resonant freq which is ~100hz. depending on things like baffle size and floor bounce.
The freq resp curves are usually done on IEC baffles, which are large flat baffles of specified size. The key is large area baffles. FYI.
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The idea is to have them at less than 2m so I think that SPL would be enough.
They're not very pretty, I found a better looking alternative though: Vifa TG9FD10/04
A few quid more but it looks good for the money. and I've had some excellent experience with Vifa drivers in my main system.
Specifications: • Power handling: 10 watts RMS/30 watts max • VCdia: 20 mm • Le: 0.024 mH • Impedance: 4 ohms • Re: 3.2 ohms • Frequency response: 115-15,000 Hz • Fs: 115 Hz • SPL: 85.3 dB 2.83V/1m • Vas: 0.05 cu. ft. • Qms: 2.67 • Qes: 1.01 • Qts: 0.73 *• Xmax: 3.15 mm • Dimensions: Overall diameter 3.85" (3.30" across flats), Cutout diameter 3.10", Depth 1.65".
Bass may still have to come from elswhere though by the sounds of it!
They're not very pretty, I found a better looking alternative though: Vifa TG9FD10/04
A few quid more but it looks good for the money. and I've had some excellent experience with Vifa drivers in my main system.
Specifications: • Power handling: 10 watts RMS/30 watts max • VCdia: 20 mm • Le: 0.024 mH • Impedance: 4 ohms • Re: 3.2 ohms • Frequency response: 115-15,000 Hz • Fs: 115 Hz • SPL: 85.3 dB 2.83V/1m • Vas: 0.05 cu. ft. • Qms: 2.67 • Qes: 1.01 • Qts: 0.73 *• Xmax: 3.15 mm • Dimensions: Overall diameter 3.85" (3.30" across flats), Cutout diameter 3.10", Depth 1.65".
Bass may still have to come from elswhere though by the sounds of it!
hello.
driver data you can find on the manufakturer's site
Visaton - Lautsprecher und Zubehör, Loudspeakers and Accessories
i have used them for many years in a closed box (around 1,5l ........2 liter).
driver data you can find on the manufakturer's site
Visaton - Lautsprecher und Zubehör, Loudspeakers and Accessories
i have used them for many years in a closed box (around 1,5l ........2 liter).
I wouldn't expect that you could get a good sounding open baffle out of a single 3", but the Needle I think was designed with that driver in mind.
http://www.diyaudio.com/forums/full-range/47403-cyburgs-needle-tangband-w3-871s.html
http://www.diyaudio.com/forums/full-range/47403-cyburgs-needle-tangband-w3-871s.html
Something like this?
Cheers Steve
An externally hosted image should be here but it was not working when we last tested it.
They hang off a T-amp driven by my computer and sound OK - they image well, as you would expect from a single driver. Bass not exactly trouser flapping as you would expect from the titchy driver and enclosure, despite a plethora of ports! As you can see, I am a fully paid up member of "what the eye don't see, the heart don't grieve about school of construction.
An externally hosted image should be here but it was not working when we last tested it.
I think without evidence that open baffle would be a bit weedy. Good luck with the build. These Visatons are decent enough for a lot of experimenting without fear of wrecking mega expensive drivers. Get stuck in, get it built and learn. Then, when the injuries have healed, do it again if you want. Fail better.
Cheers Steve
FYI, the good German loudspeaker magazine Hobby Hifi published an interesting transmission line with it:
Strassacker: Lautsprecher - Boxen - Selbstbau
It does look like an interesting little speaker.
EDIT: Oops, sorry, I was confused with the more recent and more upmarket B80. In any case, I'll leave the link as it is interesting as well.
Strassacker: Lautsprecher - Boxen - Selbstbau
It does look like an interesting little speaker.
EDIT: Oops, sorry, I was confused with the more recent and more upmarket B80. In any case, I'll leave the link as it is interesting as well.
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there's a backloaded horn Mini-Basshorn mit VISATON FRS 8 i built some years ago, but the bass was too weak and i didn't quite like them. was glad when they got stolen ;-)
two different drivers?
or
two of the same?
Probably two of the same running the same range, one in a port one not is a no no.
Unless you use a crossover, in which case two of the same is still not the best way to go.
Two in parallel will give you ~6dB of gain in sensitivity, which is good.
OB buys you not much tangible benefit in a small box/baffle. Probably gives some disadvantages.
better to define some aspect of the project more clearly - like size, position, and footprint, then look for design solutions...
There is one immutable fact, you can't get both SPL and bass and "fullrange'. Also you can't get bass out of a small box and SPL - the lower in freq you go the more you sacrifice SPL.
I have built (years ago now) small speakers that used a 5 1/4" Peerless driver, a tweeter (actually the best version used a T90 Focal, x'd over at ~2kHz.) the 5 1/4" mated to a passive radiator on the bottom, total height about 16" width 8". With the PR it was possible to do "bad alignment" and slide the PR's resonant freq down to about 35Hz or so, which made for a drop between ~100Hz and 40Hz. but to listen to it, you'd not really notice much - much better than sealed or in a port where there was nil output below about 80Hz in a box that size... it was rather nice (still is) to listen to!
Those versions were built into round tubes, but that was secondary to the basic design.
I also built versions of them using Audax 5.25" drivers and some with two Goodman's Maximus 4" drivers and three Maximus in the box! Those were very very sweet, with a warm, luscious midrange. Of course those drivers are ancient history, unobtainium today... large alnico magnet, magnesium frame, very wide cloth surround, rubberized, small cone of heavy pulp... there are some pix of the driver online to look at, somewhere.
the fullrange driver has some merits, but it is hard to achieve a truly wide range speaker, get SPL and fidelity all at once in a small enclosure...
Given that there are some exceptionally good small inexpensive (imported) printed ribbon tweeters now, it might make sense to consider a 2-way solution? This way one only needs to find a driver that is good up to ~2kHz, which is maybe an easier thing to do...
_-_-bear
or
two of the same?
Probably two of the same running the same range, one in a port one not is a no no.
Unless you use a crossover, in which case two of the same is still not the best way to go.
Two in parallel will give you ~6dB of gain in sensitivity, which is good.
OB buys you not much tangible benefit in a small box/baffle. Probably gives some disadvantages.
better to define some aspect of the project more clearly - like size, position, and footprint, then look for design solutions...
There is one immutable fact, you can't get both SPL and bass and "fullrange'. Also you can't get bass out of a small box and SPL - the lower in freq you go the more you sacrifice SPL.
I have built (years ago now) small speakers that used a 5 1/4" Peerless driver, a tweeter (actually the best version used a T90 Focal, x'd over at ~2kHz.) the 5 1/4" mated to a passive radiator on the bottom, total height about 16" width 8". With the PR it was possible to do "bad alignment" and slide the PR's resonant freq down to about 35Hz or so, which made for a drop between ~100Hz and 40Hz. but to listen to it, you'd not really notice much - much better than sealed or in a port where there was nil output below about 80Hz in a box that size... it was rather nice (still is) to listen to!
Those versions were built into round tubes, but that was secondary to the basic design.
I also built versions of them using Audax 5.25" drivers and some with two Goodman's Maximus 4" drivers and three Maximus in the box! Those were very very sweet, with a warm, luscious midrange. Of course those drivers are ancient history, unobtainium today... large alnico magnet, magnesium frame, very wide cloth surround, rubberized, small cone of heavy pulp... there are some pix of the driver online to look at, somewhere.
the fullrange driver has some merits, but it is hard to achieve a truly wide range speaker, get SPL and fidelity all at once in a small enclosure...
Given that there are some exceptionally good small inexpensive (imported) printed ribbon tweeters now, it might make sense to consider a 2-way solution? This way one only needs to find a driver that is good up to ~2kHz, which is maybe an easier thing to do...
_-_-bear
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Bear: "better to define some aspect of the project more clearly" - Very good avice!
They are to stand on the floor, within two meters of the listener who will be seated just above floor level (Japanese style).
The footprint's not a big issue but I wouldnt want it to be much more than 1'x 1'
The baffle will be in the region of 8" wide, 27" high.
The sort of ruff sketch I have in my mind at the moment would be a small OB driver at the top with a possible box at the bottom of about 10L
The amp will be a TA2021b T-Amp (25W into 4ohm), I've read that to make the most of these amps, I should aim for 4 Ohms and high efficiency
clarity/fidelity at low SPL is my primary aim, which is why OB appealed
Some bass would be good.
I live in a terrace house and these are for the evening so loud is not important.
I believe you; but what is the issue with combinig OB and Closed speakers of the same type without a X-over?
They are to stand on the floor, within two meters of the listener who will be seated just above floor level (Japanese style).
The footprint's not a big issue but I wouldnt want it to be much more than 1'x 1'
The baffle will be in the region of 8" wide, 27" high.
The sort of ruff sketch I have in my mind at the moment would be a small OB driver at the top with a possible box at the bottom of about 10L
The amp will be a TA2021b T-Amp (25W into 4ohm), I've read that to make the most of these amps, I should aim for 4 Ohms and high efficiency
clarity/fidelity at low SPL is my primary aim, which is why OB appealed
Some bass would be good.
I live in a terrace house and these are for the evening so loud is not important.
I believe you; but what is the issue with combinig OB and Closed speakers of the same type without a X-over?
The phase relationship, especially at LF will be different, therefore you will get cancellations... assuming no xover and both running fullrange. There are also cancellations due to the baffle size on an OB, and this will be different than the enclosed driver... same effect.
The distance between the top FR driver and the bottom FR driver will also have an effect WRT wavelength...
Other than that, you can do it... it will make sound, and you might be ok with the results...
_-_-bear
The distance between the top FR driver and the bottom FR driver will also have an effect WRT wavelength...
Other than that, you can do it... it will make sound, and you might be ok with the results...
_-_-bear
Sounds like a x-over will be required then; (suddenly i'm in the wrong forum).
I was reading a couple of white papers over at DECWARE. there deffinatly seems to be a bit of trial and error with OB design.
Is there any S/W that can model an OB with a Box at the same time to design a decent X-over?
I was reading a couple of white papers over at DECWARE. there deffinatly seems to be a bit of trial and error with OB design.
Is there any S/W that can model an OB with a Box at the same time to design a decent X-over?
What is the point of using two of the same drivers?
Answer: to increase the reference sensitivity and to reduce the distortion levels for a given SPL and also to increase power handling and max SPL.
There's actually a deficit to using two identical drivers of this type with a xover.
There is the added expense and the fact that this driver is not a good LF driver to start with.
Use two as both OB or both sealed/ported.
Or pick a genuine bass driver (it can be small) with a high Xmax for the low end, and put that in an appropriate enclosure or OB, and then use a xover.
Please understand that useful lower frequency limit of an OB depends in large part on the size of the baffle and/or a high Qt (which btw, the non "M" version does have) to make up for the rolloff. But that presupposed that there is ample displacement and power handling in the given driver - you have neither in this driver.
In brief, this driver is best from upper mid bass up, and in some cases with reduced max output or SPL down to "upper bass".
My opinions, again for the record I have not heard THIS particular driver myself.
_-_-bear
Answer: to increase the reference sensitivity and to reduce the distortion levels for a given SPL and also to increase power handling and max SPL.
There's actually a deficit to using two identical drivers of this type with a xover.
There is the added expense and the fact that this driver is not a good LF driver to start with.
Use two as both OB or both sealed/ported.
Or pick a genuine bass driver (it can be small) with a high Xmax for the low end, and put that in an appropriate enclosure or OB, and then use a xover.
Please understand that useful lower frequency limit of an OB depends in large part on the size of the baffle and/or a high Qt (which btw, the non "M" version does have) to make up for the rolloff. But that presupposed that there is ample displacement and power handling in the given driver - you have neither in this driver.
In brief, this driver is best from upper mid bass up, and in some cases with reduced max output or SPL down to "upper bass".
My opinions, again for the record I have not heard THIS particular driver myself.
_-_-bear
G'wan Jammy, just build - you know you want to. A box without a back is an OB (ish) so you could give that a go. If you pop one driver in a box, then fettle up a small board to support the other - you could use the front baffle from a stereo pair. Just experiment - see what happens. They are only little speakers so not much wood butchery needed. Have fun!
I tried that with FRS 8 in an improvised quite big baffle (both in open baffle) and it sounded excelente, but had it assembeled for a few days just for test. To my surprise there wern't any obvious combe efects, but when I tried two in a slimer ob in combination with 17 cm bass driver, there was combe efect so clear that it wasn't usable.
Any way I think that FRS 8 is loudspeaker that has one of the best midrange in the wordl
I have a lot of speakers inclouding B 200, B80, Fostex sigma 168 and have heard some others, also tested lowther, but this speaker is so nice to listen to that I recomend it to all, on the other hand the M version I don't like, it doesnt sound so nice.I heve them instaled in this horn http://www.picosound.de/Buschhorn.pdf and you can listen to them for hours without geting tired, they just play music.
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