Hello everyone. My first thread here on this great forum.
PROJECT: I am working on a ultra-compact near-field monitor pair with matching solo ultra-compact subwoofer. Intend to individually actively amp every driver, and feed them through multi-channel DSP. Also, intend to use only closed enclosures.
PRIORITIES: Loudness or efficiency in not a concern here, but sound quality, i.e. resolution, imaging and accuracy (in that order) at low to moderate SPLs are paramount. Application is purely musical, and hence very-low extension in not a priority, but no overhang or boominess is absolutely critical.
Seek suggestions on the following, with current choices highlighted against each: -
1. COAXIAL DRIVER: Can I find a good enough coaxial driver? How is Seas Excel C16NX001/F (E0080-04/06) Graphene cone? Or should I stick to the Magnesium cone variant C16N001/F (E0051), which is half the cost!? I am not really sure how good are the tweeters on these. Heard it may be possible to source KEF coaxial drivers, but not sure how?
2. MID-BASS DRIVER: If not coaxial, then suggestions for a good mid-bass driver which can work in a very small closed enclosure? I am inclined towards the Purifi PTT4.0M08-NAC-03. Look forward to better suggestions in the sub 1K USD per pair range.
3. TWEETER: A matching tweeter for the above? Need best possible resolution and imaging with sub 1K USD for a pair.
4. BERYLLIUM DOME: Inclined to a Beryllium dome tweeter. But confused on making a choice of exact make mode.
5. SUB-WOOFER: Suggestions for best driver suited for a small closed enclosure? Can spare up to 0.5K USD for one. Inclined towards SB Acoustics SW26DBAC76-4BLK 10 inch shallow driver due to closed-box optimised design and F3 of down to 35 Hz in a 1.2 cu-ft closed enclosure.
6. AMPLIFIER: Looking for discrete PCBs with modern Class-D designs, which I can put in my own chassis. Can do around 1K USD for the five channels of amplification needed. Suggestions please?
7. DSP: Need 8-channels for crossover and, if possible, room correction. An integrated DAC will be welcome. Inclined towards mini-DSP. Suggestions welcome…
Thanks for reading through and have a great day.
PROJECT: I am working on a ultra-compact near-field monitor pair with matching solo ultra-compact subwoofer. Intend to individually actively amp every driver, and feed them through multi-channel DSP. Also, intend to use only closed enclosures.
PRIORITIES: Loudness or efficiency in not a concern here, but sound quality, i.e. resolution, imaging and accuracy (in that order) at low to moderate SPLs are paramount. Application is purely musical, and hence very-low extension in not a priority, but no overhang or boominess is absolutely critical.
Seek suggestions on the following, with current choices highlighted against each: -
1. COAXIAL DRIVER: Can I find a good enough coaxial driver? How is Seas Excel C16NX001/F (E0080-04/06) Graphene cone? Or should I stick to the Magnesium cone variant C16N001/F (E0051), which is half the cost!? I am not really sure how good are the tweeters on these. Heard it may be possible to source KEF coaxial drivers, but not sure how?
2. MID-BASS DRIVER: If not coaxial, then suggestions for a good mid-bass driver which can work in a very small closed enclosure? I am inclined towards the Purifi PTT4.0M08-NAC-03. Look forward to better suggestions in the sub 1K USD per pair range.
3. TWEETER: A matching tweeter for the above? Need best possible resolution and imaging with sub 1K USD for a pair.
4. BERYLLIUM DOME: Inclined to a Beryllium dome tweeter. But confused on making a choice of exact make mode.
5. SUB-WOOFER: Suggestions for best driver suited for a small closed enclosure? Can spare up to 0.5K USD for one. Inclined towards SB Acoustics SW26DBAC76-4BLK 10 inch shallow driver due to closed-box optimised design and F3 of down to 35 Hz in a 1.2 cu-ft closed enclosure.
6. AMPLIFIER: Looking for discrete PCBs with modern Class-D designs, which I can put in my own chassis. Can do around 1K USD for the five channels of amplification needed. Suggestions please?
7. DSP: Need 8-channels for crossover and, if possible, room correction. An integrated DAC will be welcome. Inclined towards mini-DSP. Suggestions welcome…
Thanks for reading through and have a great day.
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Coaxial is a big rabbit hole with quickly diminishing (or negative) returns at every path. I would suggest using a compact tweeter and a small midrange driver to minimize c-to-c distance. Scan-Speak D2004-602000 and Peerless TC9FD18 are a shockingly good combo for the price.
Re: amplification - you can definitely go with something like TPA3255 for the sub, and TPA3251 with PFFB for the rest of the channels. Pre-built boards are available that are relatively easy to build out into finished amps, especially with the easy availability of Mean Well SMPS units. Alternately, you can check out the different NC252MP options out there, at potentially higher cost depending on parts & tools you have available for DIY, that are quantitatively superior but may or may not be audibly superior (human hearing being what it is).
For DSP - MiniDSP Flex Eight might work well for you. The freeDSP Aurora would have been a good option as well but it is unobtainium right now.
Re: amplification - you can definitely go with something like TPA3255 for the sub, and TPA3251 with PFFB for the rest of the channels. Pre-built boards are available that are relatively easy to build out into finished amps, especially with the easy availability of Mean Well SMPS units. Alternately, you can check out the different NC252MP options out there, at potentially higher cost depending on parts & tools you have available for DIY, that are quantitatively superior but may or may not be audibly superior (human hearing being what it is).
For DSP - MiniDSP Flex Eight might work well for you. The freeDSP Aurora would have been a good option as well but it is unobtainium right now.
Sica and B&C have likely the best small coaxes available (unless you find KEF on eBay) but they would pretty much need a 3-way build. I've thought about using them with a small woofer mounted on the rear baffle to maintain compactness, but I'm not entirely sure if that would compromise the design otherwise. The small Purifi is great but for bass use, the Kartesian Sub120_vHP needs a smaller enclosure for almost similar performance and the vHE version seems even better, though requires a bit more enclosure. You might also consider using a tweeter in an elliptical Somasonus waveguide with any of these woofers.
The SW26 is nice and proven but has rather subpar Klippel results. Kartesian once again has the Sub250 which seems nice objectively. SEAS L26RO4Y is also great in small sealed but might be slightly limited by power handling. Dayton RSS265HE might be the best thing available when it comes to parameters for compact boxes but not sure how it performs in non-linearities.
If you're smart, you might consider trying motional feedback with boards from PirateLogic - not only for the sub, but also the mains' woofers. Could produce better results even with a mid tier woofer compared to a standalone highend woofer
The SW26 is nice and proven but has rather subpar Klippel results. Kartesian once again has the Sub250 which seems nice objectively. SEAS L26RO4Y is also great in small sealed but might be slightly limited by power handling. Dayton RSS265HE might be the best thing available when it comes to parameters for compact boxes but not sure how it performs in non-linearities.
If you're smart, you might consider trying motional feedback with boards from PirateLogic - not only for the sub, but also the mains' woofers. Could produce better results even with a mid tier woofer compared to a standalone highend woofer
What is the approximate size range for the subwoofer cabinet? 20 liter? 30 l? 40 l?
In my opinion, a sealed box design will provide the highest quality of bass performance, especially in an active design where LT EQ is used.
An excellent bass driver to consider is the SB23MFCL45. I used a pair of these in an active speaker with a 34 liter sealed cabinet, so that is 17 l per woofer. With the appropriate EQ, I was able to get flat bass response down to 40 Hz, -3 dB at 35 Hz, -6 dB at 29 Hz. If you need a compact box of 16 - 25 liter, these would be a great choice. A pair of them in a 32 - 40 liter box would be excellent as well, it depends on how much SPL you need.
The SEAS L26R04Y is a great driver as well. Another 10" driver that works well in a sealed active box is the SB29NRX75-6. In a 28 liter box, with 8 dB of LT EQ, you can get -3 dB at 30 Hz.
For the midwoofer and tweeter, I found the Satori MW16TX and TW29TXT to be an excellent combination in an active speaker. My current project is using a Purifi PTT6.5M and a Satori TW29BNWG (beryllium tweeter in a waveguide), and this is an excellent combination as well, but it is twice the cost of the MW16TX + TW29TXT.
Good luck, it sounds like a very interesting project !
j.
In my opinion, a sealed box design will provide the highest quality of bass performance, especially in an active design where LT EQ is used.
An excellent bass driver to consider is the SB23MFCL45. I used a pair of these in an active speaker with a 34 liter sealed cabinet, so that is 17 l per woofer. With the appropriate EQ, I was able to get flat bass response down to 40 Hz, -3 dB at 35 Hz, -6 dB at 29 Hz. If you need a compact box of 16 - 25 liter, these would be a great choice. A pair of them in a 32 - 40 liter box would be excellent as well, it depends on how much SPL you need.
The SEAS L26R04Y is a great driver as well. Another 10" driver that works well in a sealed active box is the SB29NRX75-6. In a 28 liter box, with 8 dB of LT EQ, you can get -3 dB at 30 Hz.
For the midwoofer and tweeter, I found the Satori MW16TX and TW29TXT to be an excellent combination in an active speaker. My current project is using a Purifi PTT6.5M and a Satori TW29BNWG (beryllium tweeter in a waveguide), and this is an excellent combination as well, but it is twice the cost of the MW16TX + TW29TXT.
Good luck, it sounds like a very interesting project !
j.
thanks so much jaakkopetteri and hifijim. i am taking all inputs in to consideration, and there is so much to learn for you (and others). this build is going to be very interesting...
since, this build will have to survive tropical dusty climate, inclined to a dedicated fanless amplifier cabinet with outboard heatsinks. finding the Hyper UcD LP modules very suitable, as they can easily be mounted to a common heatsink.
i will also be doing machined aluminium cabinets for the speakers themselves. though, may not work out for the subwoofer due to size.
need more suggestions on best possible choice for beryllium tweeter please. also, hifijim, if you could throw some light on the waveguide design?
thanks momomo67890, going through sica website. any specific model you can suggest suited to meet target objectives (ultra-compact sealed enclosure)?
since, this build will have to survive tropical dusty climate, inclined to a dedicated fanless amplifier cabinet with outboard heatsinks. finding the Hyper UcD LP modules very suitable, as they can easily be mounted to a common heatsink.
i will also be doing machined aluminium cabinets for the speakers themselves. though, may not work out for the subwoofer due to size.
need more suggestions on best possible choice for beryllium tweeter please. also, hifijim, if you could throw some light on the waveguide design?
thanks momomo67890, going through sica website. any specific model you can suggest suited to meet target objectives (ultra-compact sealed enclosure)?
You can read about my Satori MW16TX + TW29TXT system here
https://www.diyaudio.com/community/threads/new-active-satori-textreme.366347/post-6493543
And my Purifi PTT6.5M + TW29BNWG waveguide tweeter system here
https://www.diyaudio.com/community/threads/purifi-waveguide-project.394174/post-7226601
I used the Hypex Fusion amps for my project. The Hypex nCore amp has great performance and it is very convenient to me that the DSP function is built into the amp and it is all mounted on a plate. Before you commit to amplifiers and DSP equipment, you should look at the Hypex Fusion to see if it meets your needs. The FA123 3-chanel amp is within your $1k price range for a pair of them.
The waveguide tweeter I use has the waveguide included with the tweeter. For me it was very convenient, since this is my first experience with a waveguide. If you have access to 3D printing, there are many waveguide designs developed by @augerpro at https://www.somasonus.net/
https://www.diyaudio.com/community/threads/new-active-satori-textreme.366347/post-6493543
And my Purifi PTT6.5M + TW29BNWG waveguide tweeter system here
https://www.diyaudio.com/community/threads/purifi-waveguide-project.394174/post-7226601
I used the Hypex Fusion amps for my project. The Hypex nCore amp has great performance and it is very convenient to me that the DSP function is built into the amp and it is all mounted on a plate. Before you commit to amplifiers and DSP equipment, you should look at the Hypex Fusion to see if it meets your needs. The FA123 3-chanel amp is within your $1k price range for a pair of them.
The waveguide tweeter I use has the waveguide included with the tweeter. For me it was very convenient, since this is my first experience with a waveguide. If you have access to 3D printing, there are many waveguide designs developed by @augerpro at https://www.somasonus.net/
Class-D amps are meant to deliver lots of power with high efficiency while occupying small spaces. If the above is true, you need to be looking not at linear (Class AB) with some useful features like overcurrent/ouput short ckt protection etc.
There are plenty of professional amplifiers (multi-channel and stereo) with good specifications available for reasonable money in India. You may read the following page / thread to get an idea of where to purchase them:
https://www.diyaudio.com/community/...ed-3-way-passive-speakers.386535/post-7038016
momomo67890, I will be building enclosures based on driver selection, most probably machined aluminium if I can arrive at a small enough size post simulations, particularly for the subwoofer. And well, small, compact, ultra are all relative terms 🙂
hifijim, I have access to most common prototyping and manufacturing processes, including 3D printing and 5-axis CNC. Your leads interest me quite a lot and appreciate them. As for amplifier modules, need them to be able to be slapped on to a common heatsink jetting outside the chassis. The Hypex UcD LP seem perfect for that.
newvirus2008, thanks for pointing to the thread. I see tons of useful information there. It will take me sometime to absorb!
Fellows, keep the suggestions coming!!
hifijim, I have access to most common prototyping and manufacturing processes, including 3D printing and 5-axis CNC. Your leads interest me quite a lot and appreciate them. As for amplifier modules, need them to be able to be slapped on to a common heatsink jetting outside the chassis. The Hypex UcD LP seem perfect for that.
newvirus2008, thanks for pointing to the thread. I see tons of useful information there. It will take me sometime to absorb!
Fellows, keep the suggestions coming!!
Sorry, please ignore the 'not' above, but I guess you still understood what I meant.
In my opinion, the most fundamental technical performance goal should be linear frequency response, and this includes on and off axis, horizontal and vertical directivity, listening window response, early reflections, and power response. Balancing all of these curves is the single most important determinant of how a speaker sounds. If we don't get the on/off axis response right, nothing else really matters.
Once we have managed and optimized the frequency response, other aspects become important. To maximize the speaker's capability for imaging and creating a sense of 3 dimensional space, diffraction control is crucial in my opinion. Diffraction below 1000 hz (the baffle step) is unavoidable, and in many cases this low frequency diffraction can be harnessed to increase directivity. The exception is flush mounted speakers which use the whole wall as the baffle. Above 1000 Hz, however, diffraction has a negative impact. Of course there is a frequency response effect that comes from this high frequency diffraction, but I have found that this diffraction reduces the imaging and 3D capability of the speaker. I think it also reduces the perception of detail. So I would recommend that you design your system with smoothly rounded or gently beveled edges around the baffle, particularly around the tweeter. Simulations are an important part of getting this right.
j.
Modern Class D is just fine. It’s not like Class AB is always better than Class D anyway.
Even non-modern Class-D with post-filter feedback is OK but these are generally not available in India and would incur import duties (usually 100%) if obtained from abroad. So why 'special money Class-D' when Class-AB available locally would work very well ?
A portion of the money saved in the amplification department could also be redirected to obtain better drivers which are more important for making good loudspeakers, as most decent amplifiers sound more or less the same (when loudspeakers don't).
A portion of the money saved in the amplification department could also be redirected to obtain better drivers which are more important for making good loudspeakers, as most decent amplifiers sound more or less the same (when loudspeakers don't).
newvirus2008, concur with you fully that drivers matter far more. My choice of class D is made due to power efficiency. Want to fit all amps in a rack mount chassis with passive heat sink.
I agree with hifijim about the SB23 Woofer. It is great! Use two in each cabinet (opposing sides) wired in parralel - here you should use 8 ohm variant.
Would say MiniDSP is much more easy to Work with than Hypex. However, Hypex Fusion DSP amps gives peace of mind, and a LOT less clutter with cables - I would not Mount Them countersinken in cabinet.
Also agree with Sica Coax. Would love to hear it in person. On paper and from review, it look very good.
https://en.toutlehautparleur.com/coaxial-speaker-sica-5-5c1-5cp-8-8-ohm-5-5-inch.html
Tip: Google Siegberg Audio. They use that driver.
Have heard seas coax in one commercial build and I think it was close to the worst Sound I have heard that whole year. My thinking is that Those drivers are very overprised for What you get.
Word of advice is also to not Fall in the trap that expensive drivers always translate to better sound. It is diminishing return the more you pay. And if you dont have much experience with crossover, you may not get the full potential.
Would say MiniDSP is much more easy to Work with than Hypex. However, Hypex Fusion DSP amps gives peace of mind, and a LOT less clutter with cables - I would not Mount Them countersinken in cabinet.
Also agree with Sica Coax. Would love to hear it in person. On paper and from review, it look very good.
https://en.toutlehautparleur.com/coaxial-speaker-sica-5-5c1-5cp-8-8-ohm-5-5-inch.html
Tip: Google Siegberg Audio. They use that driver.
Have heard seas coax in one commercial build and I think it was close to the worst Sound I have heard that whole year. My thinking is that Those drivers are very overprised for What you get.
Word of advice is also to not Fall in the trap that expensive drivers always translate to better sound. It is diminishing return the more you pay. And if you dont have much experience with crossover, you may not get the full potential.
Nearly all professional amplifier / processor units (irrespective of type) are meant for the standard 19" rack setup and have their own standalone cooling mechanisms. All you need to do is slide them in.
I would suggest that you first pick your listening distance, required peak SPL, LF/HF drivers and then work out the required amplifier power/type etc. Looking at your application, I'm sure that there would be several suitable choices for the amplifiers.
Out of curiosity, what is the situation with places like Aliexpress? Does India charge import tax/duties for items through them?
Ideally, there's an import duty on anything coming from outside India. However, small items may not be charged, like when I bought (a few years ago), something worth <10USD from Aliexpress, which reached my doorstep without any extra duties on it. Besides, I have also had 'free research samples' of ICs etc. from abroad get past without issues, several times.
But since loudspeakers / amplifiers are often not small value, they might get caught at customs after which the buyer would have to pay up and produce the paperwork to get them cleared, which is a usually a headache to the common man.
A large variety of decent HiFi drivers is hard to find here, but there are a few companies / stores that themselves import and re-sell drivers, like the ones mentioned by vineethkumar01 in the thread that I had cited above. However, in case the desired ones are not available that way, they may have to be imported.
But since loudspeakers / amplifiers are often not small value, they might get caught at customs after which the buyer would have to pay up and produce the paperwork to get them cleared, which is a usually a headache to the common man.
A large variety of decent HiFi drivers is hard to find here, but there are a few companies / stores that themselves import and re-sell drivers, like the ones mentioned by vineethkumar01 in the thread that I had cited above. However, in case the desired ones are not available that way, they may have to be imported.