I have a pair of 8" woofers that I am somewhat fond of, and I'd like to join them with tweeters to make a pair of inexpensive systems.
The ScanSpeak D2606/9200 is about the right price and it looks okay on paper but there isn't much in Google about it, which says to me that it isn't very popular. Does anyone have any experience with it to share?
Or anything that you think is better in that price range (about $35US)? I can't have a very high crossover frequency from an 8" driver, and I don't like spiky response. Apart from that I'm pretty open.
Thanks
The ScanSpeak D2606/9200 is about the right price and it looks okay on paper but there isn't much in Google about it, which says to me that it isn't very popular. Does anyone have any experience with it to share?
Or anything that you think is better in that price range (about $35US)? I can't have a very high crossover frequency from an 8" driver, and I don't like spiky response. Apart from that I'm pretty open.
Thanks
... with an 8" I'd always be looking at a 3-way, especially given the massive advantaged it can give, out of budget?
Oh, and the scanspeak D2606/9200 is actually an old vifa tweeter that's been re-badged, and when it was a vifa tweeter it was exactly the same as yet another tweeter used in many very good 2-way and 3-way speakers, including studio monitors, so it has decent enough potential. My main concern would be mid-to-mid distance and all the associated issues, and it's not a tweeter I'd cross low.... personally about 2.5 LR2 for a start point, I wouldn't want to push it much lower.
The trouble with an 8" driver is it's requirement for a low crossover frequency. Ideally you'd want to cross below 1500Hz. This requires a very robust tweeter and something like the Seas 27TDFCl would be a very good idea, especially if you want the speaker to remain clean at higher listening levels. This will require a 4th order acounstic target function to work correctly. The scanspeak d2604/833000 would also work, but perhaps not go tremendously loudly as it's distortion has already started to rise a little by 1.5k, although the higher order products are well suppressed.
The other option would be to use an 8" wave guide mounted to a standard dome tweeter. If done like this you can crossover at around 2kHz and get a good directivity match between the woofer and the tweeter. This also relaxes the tweeter requirement, so you could go for something less capable. There are lots of cheaper tweeters out there that will handle 2kHz, 4th order acoustic, but far fewer that will cope with 1.5k.
Something like the Vifa OT19NC00 would work very well in combination with https://www.parts-express.com/dayton-audio-h08rw-8-round-waveguide-1-threaded--270-308
This will require some experimentation and you will have to measure to ensure good results, but you'd need to do that anyway with any 8" + 1" design.
The other option would be to use an 8" wave guide mounted to a standard dome tweeter. If done like this you can crossover at around 2kHz and get a good directivity match between the woofer and the tweeter. This also relaxes the tweeter requirement, so you could go for something less capable. There are lots of cheaper tweeters out there that will handle 2kHz, 4th order acoustic, but far fewer that will cope with 1.5k.
Something like the Vifa OT19NC00 would work very well in combination with https://www.parts-express.com/dayton-audio-h08rw-8-round-waveguide-1-threaded--270-308
This will require some experimentation and you will have to measure to ensure good results, but you'd need to do that anyway with any 8" + 1" design.
I should mention that I'm never going to play them very loudly. When the guy who cranks the music up all the way arrives at the party, I leave.
And I don't need ultrasonic response either. As you may have gathered, I'm old and my hearing doesn't go up to 20kHz any more.
I was thinking maybe 1500Hz but I haven't measured the woofers yet so I'm blind at this point. The Dynaco A-25 and the original Advent had crossovers down there (I believe), and they got by.
And I don't need ultrasonic response either. As you may have gathered, I'm old and my hearing doesn't go up to 20kHz any more.
I was thinking maybe 1500Hz but I haven't measured the woofers yet so I'm blind at this point. The Dynaco A-25 and the original Advent had crossovers down there (I believe), and they got by.
I wonder whether there's anything worthwhile in the format of those little 2" "full-range" speakers -- the ones with cones like inverted domes....
The format would be perfect, although I don't know whether there are any really hi-fi ones...
The format would be perfect, although I don't know whether there are any really hi-fi ones...
Vifa TC9FD-18-08 3-1/2" Full Range Paper Cone Woofer
This would probably exceed your expectations and comes well within budget.
Xover 400 or above.
Good luck.
This would probably exceed your expectations and comes well within budget.
Xover 400 or above.
Good luck.
If the sensitivity of the SB65WBAC fits the bill. Then you cannot go wrong with that when using it as an upper mid/tweeter. Sure it's off axis isn't the same as a 1" dome, but what it does do, it does very well indeed.
It's roughly an 83dB sensitivity driver when driven with 2.83vrms and is a 4 ohm unit. It's 8 ohm sensitivity is therefore low at around 80dB, but this may not be of great concern.
If you do go this route you would be building essentially, what is known as a FAST system. Otherwise known as a full range assisted loudspeaker.
If you are to place the loudspeaker in free space, then you're going to want to apply 5-6dB of bafflestep compensation to it anyway. Naturally you want to cross over the full range to the bass driver before baffle step occurs, so all of the usual sensitivity losses associated with baffle step compensation occur within the woofers pass band.
If your 8" driver has a sensitivity of say 88dB and you apply 5dB of compensation to it, you end up with an overall net sensitivity of around 83dB. This is perfect for mating to the SB.
This approach can work, and work very well, you just have to know what it is you're doing to make it work properly.
If you are not going to play them very loud then this does relax the requirements on the tweeter and means you can go with something a little less robust, but I would still be wanting to use something like the SEAS 27TDFC. The scanspeak d2604/833000 would also work.
As another option the Vifa DQ25SC16, could probably just about handle a steep 1.5kHz xover at lower listening levels.
Whatever route you go, with a tweeter, you will need to get the xover just right because you will be using it right on the edge of it's operational limits and this adds in complications, you will not get much room for error.
It's roughly an 83dB sensitivity driver when driven with 2.83vrms and is a 4 ohm unit. It's 8 ohm sensitivity is therefore low at around 80dB, but this may not be of great concern.
If you do go this route you would be building essentially, what is known as a FAST system. Otherwise known as a full range assisted loudspeaker.
If you are to place the loudspeaker in free space, then you're going to want to apply 5-6dB of bafflestep compensation to it anyway. Naturally you want to cross over the full range to the bass driver before baffle step occurs, so all of the usual sensitivity losses associated with baffle step compensation occur within the woofers pass band.
If your 8" driver has a sensitivity of say 88dB and you apply 5dB of compensation to it, you end up with an overall net sensitivity of around 83dB. This is perfect for mating to the SB.
This approach can work, and work very well, you just have to know what it is you're doing to make it work properly.
If you are not going to play them very loud then this does relax the requirements on the tweeter and means you can go with something a little less robust, but I would still be wanting to use something like the SEAS 27TDFC. The scanspeak d2604/833000 would also work.
As another option the Vifa DQ25SC16, could probably just about handle a steep 1.5kHz xover at lower listening levels.
Whatever route you go, with a tweeter, you will need to get the xover just right because you will be using it right on the edge of it's operational limits and this adds in complications, you will not get much room for error.
A big plus 1 for the sb acoustics, it's not a driver I've seen but sb equipment I've come accross has been reliable in terms of matching supplied data, consistent, and much better quality than the price reflects. Looking at the construction of that litte 2.5 it's easy to see it's well made.
Given the low listening levels and stated contentment with limited HF response I'd have thought it was a no brainer...
Given the low listening levels and stated contentment with limited HF response I'd have thought it was a no brainer...
SB Acoustics SB65... looks nice, but I don't know how to deal with that 4 ohms. The amplifier is a small tube job with an output that's not very stiff.
I'm thinking, too, that maybe during this conversation I'm forming a perception that a one-inch-diaphragm is too small and a three-inch diaphragm is too large. Which sums out to a two-inch diaphragm being perfect.
The SB isn't a 3" driver, it is in between 2 and 3 ^^ 4 ohms isn't an issue from the point of designing a loudspeaker, but if you're amplifier is going to have trouble driving it then this could be a problem. Do you know what the 8" woofers are?
Have you considered a (slightly) larger tweeter?
On a budget the Monacor DT300 with the dirt-cheap waveguide might be ok down to 1.5kHz if you don't brutalize it.
On a budget the Monacor DT300 with the dirt-cheap waveguide might be ok down to 1.5kHz if you don't brutalize it.
Oh, I'll consider anything. What have you got?
I don't think that we have Monacor in the US.
My knowledge of horns (waveguide is just a fancy word for horn) stops in the 1970s, but I believe that they have a distinct low-frequency limit owing to the flare rate. I can't presume that any horn would cover what I want to cover without specific assertion that it would.
It might be nice for alignment, though...
I don't think that we have Monacor in the US.
My knowledge of horns (waveguide is just a fancy word for horn) stops in the 1970s, but I believe that they have a distinct low-frequency limit owing to the flare rate. I can't presume that any horn would cover what I want to cover without specific assertion that it would.
It might be nice for alignment, though...
Just been on Monacors homepage and it seems they don't have North American distribution.
Shame because I've never seen a bad opinion of this tweeter especially since it only costs £20 here and the waveguide £6.59.
There are actual measurements on the web and it seems to be consistent (the guy in Germany tested 4 of them), distortion pretty low and useable from 1.5k although the impedance makes designing a passive xover a bit of challenge.
There was an english-language site with measurements but it seems the server does not exist anymore so here is the german one: Test Monacor DT-300 am Waveguide WG-300
The waveguide increases low output by 6-8dB but a single cap would flatten that out again.
Shame because I've never seen a bad opinion of this tweeter especially since it only costs £20 here and the waveguide £6.59.
There are actual measurements on the web and it seems to be consistent (the guy in Germany tested 4 of them), distortion pretty low and useable from 1.5k although the impedance makes designing a passive xover a bit of challenge.
There was an english-language site with measurements but it seems the server does not exist anymore so here is the german one: Test Monacor DT-300 am Waveguide WG-300
The waveguide increases low output by 6-8dB but a single cap would flatten that out again.
Well, the high-frequency is a little wiggly but I'm not building this for it to be correct, I'm building it for it to be enjoyable. I wonder how large this whole thing is.
The Google Chrome browser translates sites so I didn't have to try to remember my high-school German.
You asked what the woofers are -- they're old alnico Scan-Speak 8" with model numbers that I can't read. Not particularly heavy magnets. Copper cap inside under the dome. You know how sometimes you listen to an elaborate system and it sounds great and you turn it off. Then you drag out a pair of Dynaco A25s and you're up all night listening to records. The latter is what I'm aiming for, and if it's higher fi than the old Dynaco that's gravy.
The Google Chrome browser translates sites so I didn't have to try to remember my high-school German.
You asked what the woofers are -- they're old alnico Scan-Speak 8" with model numbers that I can't read. Not particularly heavy magnets. Copper cap inside under the dome. You know how sometimes you listen to an elaborate system and it sounds great and you turn it off. Then you drag out a pair of Dynaco A25s and you're up all night listening to records. The latter is what I'm aiming for, and if it's higher fi than the old Dynaco that's gravy.
Well you know a nice wave guide design will have a listen all day quality to it, that works well with most rooms and will have great imaging.
Most wave guide designs have issues within the top octave, but they are usually not much of a concern.
Most wave guide designs have issues within the top octave, but they are usually not much of a concern.
Here is a link that hopefully works: Monacor :: Monacor DT-300 HiFi Dome Tweeter 20.59
The waveguide is 169mm ø , about 6.5".
The waveguide is 169mm ø , about 6.5".
Well, I never would have naturally associated pleasant listening with aluminum cones and horns, but my experience is not comprehensive.
I can't get Monacor here and it's too expensive anyway. US$100+ for a pair of tweeters may be cheap in the high-end world but in the normal people world it's a game-stopper.
Now, it seems that something like this
AuraSound NS2-326-8AT Whisper 2" Extended Range Speaker Driver 8 Ohm
or this
Tang Band W2-748SG 2" Full Range Driver
would be an obvious solution to the initial circumstances. So why not?
Maybe I should open another thread headlined with drivers like these in order to elicit some experiences in that realm.
I can't get Monacor here and it's too expensive anyway. US$100+ for a pair of tweeters may be cheap in the high-end world but in the normal people world it's a game-stopper.
Now, it seems that something like this
AuraSound NS2-326-8AT Whisper 2" Extended Range Speaker Driver 8 Ohm
or this
Tang Band W2-748SG 2" Full Range Driver
would be an obvious solution to the initial circumstances. So why not?
Maybe I should open another thread headlined with drivers like these in order to elicit some experiences in that realm.
Not quite sure where you get 'aluminium cones and horns' from when I linked to a silk dome tweeter and an ABS waveguide but Monacor not being available in the US would be a problem.
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