Which would be a nice mid-woofer mate for a small box, closed or vented, using the Vifa XT25SC90 as tweeter?
It should be something from 4" to 5.25".
It should be something from 4" to 5.25".
Interesting combo. This whole project started with Madisound's ZA5.2 kit, based on the ZA14.
But I didn't like the kit's Vifa tweeter, so I looked for something different. Thought the SB29RDCN might a better choice, if I am going to listen to it all day.
As the xover would have to be re-designed anyway, I looked for other options to the ZA14. Simulated them in Bassbox 6 Pro, in closed and vented versions.
To my surprise, I got the better low end response prediction from another SB speaker: SB Acoustics SB12NRX2504. 56Hz for F3.
As so many projects are using radiator ring tweeters, I thought why not try one. And that's how I got to the Vifa XT25SC90.
And now you put the Zaph ZA14 once again into the picture. A complete circle.
You're right about the ZA14 lack of real bass, as BB6 diagnosed an F3 of 87Hz. In any case, we must not forget this is a near-field project.
So I ask, if , why not mate the XT25SC90 with the SB12NRX2504?
But I didn't like the kit's Vifa tweeter, so I looked for something different. Thought the SB29RDCN might a better choice, if I am going to listen to it all day.
As the xover would have to be re-designed anyway, I looked for other options to the ZA14. Simulated them in Bassbox 6 Pro, in closed and vented versions.
To my surprise, I got the better low end response prediction from another SB speaker: SB Acoustics SB12NRX2504. 56Hz for F3.
As so many projects are using radiator ring tweeters, I thought why not try one. And that's how I got to the Vifa XT25SC90.
And now you put the Zaph ZA14 once again into the picture. A complete circle.
You're right about the ZA14 lack of real bass, as BB6 diagnosed an F3 of 87Hz. In any case, we must not forget this is a near-field project.
So I ask, if , why not mate the XT25SC90 with the SB12NRX2504?
The SB12NRX2504 is a perfect choice for the XT25SC90. This mid-woofer is very impressive. Loaded in BR box:
5.5L box ---> F3=55Hz
8L box ---> F3=47Hz
Best of all, the Voice Coil Linear Travel = 10mm p-p. With contouring, you can get this 4 inch to kick some bass.
The SB12NRX2504 can easily be crossed at 3,500Hz with the XT25SC90. I find that below 3,500HZ, the Vifa starts to strain. Try to keep the tweeter at 3rd or 4th order.
5.5L box ---> F3=55Hz
8L box ---> F3=47Hz
Best of all, the Voice Coil Linear Travel = 10mm p-p. With contouring, you can get this 4 inch to kick some bass.
The SB12NRX2504 can easily be crossed at 3,500Hz with the XT25SC90. I find that below 3,500HZ, the Vifa starts to strain. Try to keep the tweeter at 3rd or 4th order.
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That's very good news you are also impressed with the SB mid woof. My guess was the VC Xmax was a good place to start. I think that driver remains one to be discovered, as I think it's the best of SB's small drivers. I compared it to the new Vifa NE (very nice) and some Scanspeaks, and I think only the SS 5" Revelator improves on it. For a lot more money.
With your suggestion on where to cross it, which I agree with, I might simply use this 18dB/oct xover for the Vifa XT.
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I guess I can get away with a 12dB/oct for the SB too, but I'm still trying to learn how to simulate it all with FRD tools.
FRD Consortium
An 8-liter vented box is a very good suggestion, but modeling and first tests will be done on an existing 5 liter box I have: 220mm h x 120mm w x 120mm d. What do you think?
With your suggestion on where to cross it, which I agree with, I might simply use this 18dB/oct xover for the Vifa XT.
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I guess I can get away with a 12dB/oct for the SB too, but I'm still trying to learn how to simulate it all with FRD tools.
FRD Consortium
An 8-liter vented box is a very good suggestion, but modeling and first tests will be done on an existing 5 liter box I have: 220mm h x 120mm w x 120mm d. What do you think?
Feel free to use the 18dB/oct crossover for the Vifa XT.
Though this tweeter is very good, I should mention that you won't get the "presence" in the vocals. For the mids/vocals to be forward, I have to resort to tweeters that can be crossed lower (in the region of 2kHz).
For tweeters like the XT that crosses at 3K~4K, I use them in speakers for general listening. Great for background music while on the computer.
The SB mid-woofer will be fine in a 5L box. According to modeling, 5.5L is optimum. This is about the same size as my Hafler M5 near field monitors. I'm sure your speakers will sound better. In my M5, the mids are muffled.
Apart from the crossover, I strongly recommend adding some contouring for bass. It will be a waste if there's no bass punch with these SB.
Though this tweeter is very good, I should mention that you won't get the "presence" in the vocals. For the mids/vocals to be forward, I have to resort to tweeters that can be crossed lower (in the region of 2kHz).
For tweeters like the XT that crosses at 3K~4K, I use them in speakers for general listening. Great for background music while on the computer.
The SB mid-woofer will be fine in a 5L box. According to modeling, 5.5L is optimum. This is about the same size as my Hafler M5 near field monitors. I'm sure your speakers will sound better. In my M5, the mids are muffled.
Apart from the crossover, I strongly recommend adding some contouring for bass. It will be a waste if there's no bass punch with these SB.
Just now did I realize that the Swift project was your design. Congratulations!
I would love to listen to it, and it probably sounds better than the ZA5-2.
Your comments about the vocals presence might have to do with those "pits" in 1800 and 3000Hz. Zaph's roughness perhaps? Why shouldn't the main driver fulfill its mid functions as it should and be smooth there, providing all the presence you need?
OTOS, did you try crossing at 2500Hz? Or is the XT frequency spec wrong?
Should I consider going back to the SB29RDCN?
https://www.madisound.com/store/manuals/SB29RDCN-C000-4.pdf
That one might be crossed at 2K me thinks...
I would love to listen to it, and it probably sounds better than the ZA5-2.
Your comments about the vocals presence might have to do with those "pits" in 1800 and 3000Hz. Zaph's roughness perhaps? Why shouldn't the main driver fulfill its mid functions as it should and be smooth there, providing all the presence you need?
OTOS, did you try crossing at 2500Hz? Or is the XT frequency spec wrong?
Should I consider going back to the SB29RDCN?
https://www.madisound.com/store/manuals/SB29RDCN-C000-4.pdf
That one might be crossed at 2K me thinks...
Thanks for the compliments. Even though I design amps, I enjoy designing speakers too.
I have not listened to the ZA5-2, so can't really comment. What I can say is after testing out Zaph's ZA14, they are quite good drivers. Fast and clean. Suitable for near field vocal monitoring where bass is not really required, or desired for that matter. For full range, they will work great as satellites, especially in closed box where F3 is about 100-150Hz. Below that, a sub can take over.
With regards to the lack of presence in the vocals, I don't think it has to do with the ZA14. It's not that there's no vocals or they sound muddy. Just that when I cross any mid-woofers at 3-4kHz, I don't get the kind of forwardness and clarity that a good compression driver and horn can give.
My initial test of the Vifa XT was at 2.5kHz at 18dB/oct. The tweeter sounded strained. Moved up to 3kHz. Still not right. Only at 3,500Hz, the XT sounded sweet. For other listeners, it may be fine at 2,500Hz. Different people hear differently. Maybe my ears are sensitive to tweeter resonance.
Personally, I would use the SB29RDCN with the SB12NRX2504. I have not tried the SB29 tweeter but judging from the specs, it should be able to cross at 2kHz to 2.2kHz. I know the Seas 27TDFC can do 2.2kHz at 18dB/oct. Did that with a Seas ER18RNX. When I crossed the 27TDFC actively at 18dB/oct, I even managed 2.0kHz. In fact, I'm listening to it now with my Biamp Kit.
I have not listened to the ZA5-2, so can't really comment. What I can say is after testing out Zaph's ZA14, they are quite good drivers. Fast and clean. Suitable for near field vocal monitoring where bass is not really required, or desired for that matter. For full range, they will work great as satellites, especially in closed box where F3 is about 100-150Hz. Below that, a sub can take over.
With regards to the lack of presence in the vocals, I don't think it has to do with the ZA14. It's not that there's no vocals or they sound muddy. Just that when I cross any mid-woofers at 3-4kHz, I don't get the kind of forwardness and clarity that a good compression driver and horn can give.
My initial test of the Vifa XT was at 2.5kHz at 18dB/oct. The tweeter sounded strained. Moved up to 3kHz. Still not right. Only at 3,500Hz, the XT sounded sweet. For other listeners, it may be fine at 2,500Hz. Different people hear differently. Maybe my ears are sensitive to tweeter resonance.
Personally, I would use the SB29RDCN with the SB12NRX2504. I have not tried the SB29 tweeter but judging from the specs, it should be able to cross at 2kHz to 2.2kHz. I know the Seas 27TDFC can do 2.2kHz at 18dB/oct. Did that with a Seas ER18RNX. When I crossed the 27TDFC actively at 18dB/oct, I even managed 2.0kHz. In fact, I'm listening to it now with my Biamp Kit.
Very interesting amp design the Synergy. Congratulations too.
An active amp like yours allows trying different frequency points to cross before designing the passive xover. Very clever.
I'm also into amp design and built a pro portable microphone preamp some time ago, that sold in the US.
The Seas 27TDFC is a very nice tweeter, even if in Zaph's tweeter testing the simpler 27TDF looks cleaner. But both tweeters suffer a bit when compared to the SB29EDCN, which could be crossed at 2K with no strain.
It seems that my guess of using two SB units for this design was not bad after all. Pity it would cost me $44 more to see if I am right.
An active amp like yours allows trying different frequency points to cross before designing the passive xover. Very clever.
I'm also into amp design and built a pro portable microphone preamp some time ago, that sold in the US.
The Seas 27TDFC is a very nice tweeter, even if in Zaph's tweeter testing the simpler 27TDF looks cleaner. But both tweeters suffer a bit when compared to the SB29EDCN, which could be crossed at 2K with no strain.
It seems that my guess of using two SB units for this design was not bad after all. Pity it would cost me $44 more to see if I am right.
An additional note.
Today I decided to investigate passive radiators a little to consider using them on this project.
Apparently the woofer's Qts should be less than 0.4 to get better results with a PR, and you don't need to use the same woofer's size for the PR.
So I may put a 5.25" Peerless 830880 with my SB 4" woofer, which does have a Qts = 0.4 and get better results than with vented box.
It seems like a nice icing on my cake, don't you think?
Today I decided to investigate passive radiators a little to consider using them on this project.
Apparently the woofer's Qts should be less than 0.4 to get better results with a PR, and you don't need to use the same woofer's size for the PR.
So I may put a 5.25" Peerless 830880 with my SB 4" woofer, which does have a Qts = 0.4 and get better results than with vented box.
It seems like a nice icing on my cake, don't you think?
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Thanks. The Synergy came about from my frustrations with testing drivers. It's really troublesome and time consuming to have to design passive crossovers when all I want is to audition the drivers. Only after I listen to them do I decide on how to use them. The spec sheets are useful technically, but they don't tell me how the drivers sound like.
Before the Synergy, I was using commercial electronic crossovers. They are very convenient being adjustable but I find the quality lacking. I wanted something more precise and more transparent. I don't want to be able to hear the crossover. That was the biggest hurdle with the Synergy, to design the crossover so that it's invisible.
It does cost more with both SB but I think you are after quality. Otherwise, why pay for the SB 4" mid-woofer. There are many others at half the price. With the cheaper mid-woofers, the Vifa XT would be a better choice.
If you don't mind a bigger box (15L to 18L), consider using a larger mid-woofer. With some contouring, my Seas ER18RNX is punching out some great bass. Saves me the trouble of blending in my subs.
If I go seriously into speaker design, which I doubt, I will build a settable active xover. It's certainly the way to go.
For this project I can't use a larger box, certainly not larger than 8 liter tops. 4" or 5" is me most I can afford. This is mainly a near-field box.
If it does do well on other tasks, fine, but my aim is for a quality near-field. As good as I can get it, even if affordable.
I'm betting I can get some more bass from it, particularly if I can use a passive radiator as I suggested above.
I didn't find that many cheap mid-woofers around, or they were lacking in Xmax, like the Peerless 4" and 5".
Now the question is how to simulate these drivers to see how they might do together, and where to better cross them. 2K or so seems like a good bet for the cross too.
For this project I can't use a larger box, certainly not larger than 8 liter tops. 4" or 5" is me most I can afford. This is mainly a near-field box.
If it does do well on other tasks, fine, but my aim is for a quality near-field. As good as I can get it, even if affordable.
I'm betting I can get some more bass from it, particularly if I can use a passive radiator as I suggested above.
I didn't find that many cheap mid-woofers around, or they were lacking in Xmax, like the Peerless 4" and 5".
Now the question is how to simulate these drivers to see how they might do together, and where to better cross them. 2K or so seems like a good bet for the cross too.
Sorry for not replying sooner. Been busy test driving Linux Ubuntu. So much more friendly than in the early years. I remember I had to manually mount the cd drive in Red Hat.
I'm afraid I am not versed in simulation, otherwise I don't mind helping out. I use LMS exclusively, so everything is in real time. Very accurate but time consuming.
Are you planning to use the speakers for studio recording (hence near field)?
I'm afraid I am not versed in simulation, otherwise I don't mind helping out. I use LMS exclusively, so everything is in real time. Very accurate but time consuming.
Are you planning to use the speakers for studio recording (hence near field)?
Well, I will be editing some films on my setup, using Avid. Documentaries, so 5.1 mix won't be necessary.
That's why I would like some accuracy.
The near-field, obviously, is because speakers will be quite close by, about 1 meter at most, and ear level.
That's why I would like some accuracy.
The near-field, obviously, is because speakers will be quite close by, about 1 meter at most, and ear level.
I thought you will need them for professional work. I did some recording and mixing in the 80s. Mainly for multi-media productions (computerized slide shows). I've been out of production industry for almost 20 years since.
For near field studio use, I would go for a response similar to the Yamaha NS-10M. As flat as possible with a slight peak at about 2kHz. I wouldn't want my speakers to go too low because I use near field for vocals and highs. I would also choose a sealed (closed) box with it's gentler roll off over a bass reflex. Critical for me is the transparency. If the vocals are blur/muddy, it's very difficult to mix. Of course, this is just my preference. More important is for you to decide what is right. These will be your working tools, so it's crucial that you are comfortable with them.
For near field studio use, I would go for a response similar to the Yamaha NS-10M. As flat as possible with a slight peak at about 2kHz. I wouldn't want my speakers to go too low because I use near field for vocals and highs. I would also choose a sealed (closed) box with it's gentler roll off over a bass reflex. Critical for me is the transparency. If the vocals are blur/muddy, it's very difficult to mix. Of course, this is just my preference. More important is for you to decide what is right. These will be your working tools, so it's crucial that you are comfortable with them.
If there's something I want to stay away from is the sound of NS-10M. I think it's too boring. But it's interesting to note that it was crossed at 2K using a paper cone. In fact a lower cut tweeter candidate like the SB it's clearly defining as the way to go here.
Did you know that the NS10 was a disaster in selling for home audio and was sent free of charge to studios? And it's said that the fact that the cone was white was also a factor in becoming popular in studios, where everything was grey or black.
It was also portable, and producers started taking it around to be their reference in different studios. Even if it was not great, at least they knew how it sounded.
Very low frequencies are certainly not necessary in these speakers. But I would like them to be as flat as possible. Apparently Variovents are the way to go to get some bass in a closed box and still have a gentle bass roll-off.
Some side notes...
Drop a 30-33 ohm resistor across the XT25SC90, and that will eliminate some of the Fs spike's output. The problem with these XT tweeters is that the Fs is severely undamped. I needed a full notch on the TG30 xover'd at 2.3kHz, and the SC50 or SC90 xover'd at 3.2kHz still required the 33 ohmer.
This is before the resistor:
Definitely present, but nasality disappeared after that addition.
Later,
Wolf
Drop a 30-33 ohm resistor across the XT25SC90, and that will eliminate some of the Fs spike's output. The problem with these XT tweeters is that the Fs is severely undamped. I needed a full notch on the TG30 xover'd at 2.3kHz, and the SC50 or SC90 xover'd at 3.2kHz still required the 33 ohmer.
This is before the resistor:
Definitely present, but nasality disappeared after that addition.
Later,
Wolf
They are more then boring. Sounds horrible for Hi-Fi. But it's not just the NS-10M. You may notice that other Near Field Monitors are not as pleasing to listen to as well.
For Near Field recording purposes, I require a speaker with a flat response. The reason being that flat is the most practical reference. Anything I do, like eq or adding effects, I always have a reference point. My primary usage is for vocal monitoring. For the lower frequencies, I switch over to the main/house speakers. These are usually 10-12" woofers.
When I listen to music, I don't use Flat Response speakers. They simply don't sound right. To me at least. Instead, I contour the speakers to fit my ears.
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