Hello!
I'm about to build my first vented enclosure. I decided to use Markaudio CHR-70.3 again, my first project was this, sealed cubes: Cube shaped speakers
Since floorstanders require more advanced woodworking skills and I'm a beginner I decided to build bookshelf speakers, but I would also like to get as much low end as possible. So the bookshelf design can be quite large, up to 50cm height.
I am planning to build the first one(A), Mark 9 from Strassacker, since it's the largest bookshelf design for CHR-70.3 I could find online. How do these two compare?
A. Mark 9
B. CHR 70 Chamagne | Markaudio Slim-deeper bass reflex box
My questions are:
1. I assume the A can deliver better low end?
2. Strassacker site states frequency range (-8dB): 38 - 30000 Hz. How do I compare these numbers to commercial speakers which usually state the frequency range at +/-3 dB?
3. The Markaudio Slim-deeper box states resonance frequency (Fb) 57Hz. How do I compare this number to Strassacker frequency range or commerical speaker frequency ranges?
Thank you!
I'm about to build my first vented enclosure. I decided to use Markaudio CHR-70.3 again, my first project was this, sealed cubes: Cube shaped speakers
Since floorstanders require more advanced woodworking skills and I'm a beginner I decided to build bookshelf speakers, but I would also like to get as much low end as possible. So the bookshelf design can be quite large, up to 50cm height.
I am planning to build the first one(A), Mark 9 from Strassacker, since it's the largest bookshelf design for CHR-70.3 I could find online. How do these two compare?
A. Mark 9
B. CHR 70 Chamagne | Markaudio Slim-deeper bass reflex box
My questions are:
1. I assume the A can deliver better low end?
2. Strassacker site states frequency range (-8dB): 38 - 30000 Hz. How do I compare these numbers to commercial speakers which usually state the frequency range at +/-3 dB?
3. The Markaudio Slim-deeper box states resonance frequency (Fb) 57Hz. How do I compare this number to Strassacker frequency range or commerical speaker frequency ranges?
Thank you!
In all honesty, a tall speaker such as a Pensil (http://frugal-phile.com/boxlib/pensils/Pensil-R70s3-map.pdf) will give you better bass than most bass reflex speakers and the level of difficulty is probably less since the vent is acquired by cutting one piece of material a bit shorter than the others; no hole to cut to fit a port tube into.
Mike
Mike
If you are looking to maximize bass, the Pensil or Frugel-Horn Mk3.
A larger vented box only gives deeper bass if it is an ugly alignment or a shelf at a step lower amplitude. The largest vented box i use for the CHR70.3 is 9 litres (but with somewhat resistive vents). Look here: Frugal-phile | Box Library / Mark Audio
The Mark 9 is about 8.5 litre.
If you haven’t gotten the drivers yet the Pluvia 7 is a much better driver for not much more money. You also do not absolutely require a rebate. It does need a larger reflex box but is capable of a fair bit more bass extension than the CHR.
dave
A larger vented box only gives deeper bass if it is an ugly alignment or a shelf at a step lower amplitude. The largest vented box i use for the CHR70.3 is 9 litres (but with somewhat resistive vents). Look here: Frugal-phile | Box Library / Mark Audio
The Mark 9 is about 8.5 litre.
If you haven’t gotten the drivers yet the Pluvia 7 is a much better driver for not much more money. You also do not absolutely require a rebate. It does need a larger reflex box but is capable of a fair bit more bass extension than the CHR.
dave
After building dozens of pairs of enclosures for almost every model of Mark Audio driver since day one, my vote would always be for a floorstander - the Pensils are an easier build with greater flexibility of placement, and while a slightly trickier build, given sufficient floorspace the FrugelHorns will definitely outperform any bookshelf type I’ve heard with the same driver model.
Thank you for all the replies.
The size makes gluing the cabinets more difficult, at least to me. And finishing the speakers takes also lot more time when the surface area is twice as large. I hope I will graduate to floorstanders with my next project 🙂
I already had ordered the drivers, so I think will try the Mark 9 desing. I will let you know how it turns out and post pictures here.
I think my next project after that will be a Pensil design with Alpair 11MS - I assume this driver at the moment is the most low-end capable driver from Markaudio.
The size makes gluing the cabinets more difficult, at least to me. And finishing the speakers takes also lot more time when the surface area is twice as large. I hope I will graduate to floorstanders with my next project 🙂
I already had ordered the drivers, so I think will try the Mark 9 desing. I will let you know how it turns out and post pictures here.
I think my next project after that will be a Pensil design with Alpair 11MS - I assume this driver at the moment is the most low-end capable driver from Markaudio.
Hi guys.
I also get a pair of CHR-70.3 , now im trying to choose the box. I would like to get a smaller/Bookshelft size box with the lowest F3 possible 🍰😏
Does any one know the FB/F3 of these box:
https://www.markaudio.com/wp-content/uploads/2021/08/Fenlon-70CHR.png
and
https://www.markaudio.com/wp-content/uploads/2022/09/CHR70.3-twin-vent.png
Also, in this second box..its smaller, i like it the most..but it could damage or change the design of the box response if i move the ports to the front wafle?
THANkS a lot
From Bogota 🇨🇴
I also get a pair of CHR-70.3 , now im trying to choose the box. I would like to get a smaller/Bookshelft size box with the lowest F3 possible 🍰😏
Does any one know the FB/F3 of these box:
https://www.markaudio.com/wp-content/uploads/2021/08/Fenlon-70CHR.png
and
https://www.markaudio.com/wp-content/uploads/2022/09/CHR70.3-twin-vent.png
Also, in this second box..its smaller, i like it the most..but it could damage or change the design of the box response if i move the ports to the front wafle?
THANkS a lot
From Bogota 🇨🇴
No, it won't change the response itself if you move the vents to the front baffle so you should be fine from that POV. I'll need to double-check the other as that was Mark's design & I don't have any records of the tuning details off-hand -will try to have a look later when I'm on my main machine. Apologies in advance if it takes a little while as I've got to take the car in for its service in an hour or so, so probably won't have chance until I get back.
THANKS a lot Scott to take the time to answer. Please do not apologies, thanks again!👍👍
Just another question..taking advance of the famous british courtesy.. in the pdf for the twin vent box, talk about the bracing..i got the pensil 12 for the info..but that will not reduce the overall volumen of the box?..if i need to compensate, how can i do it? adding the same width as the brace itselft? 🤔
Just another question..taking advance of the famous british courtesy.. in the pdf for the twin vent box, talk about the bracing..i got the pensil 12 for the info..but that will not reduce the overall volumen of the box?..if i need to compensate, how can i do it? adding the same width as the brace itselft? 🤔
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Yes th ebrace east some volume. If you hit the target holes the brace has a volume ~ the same as ⅔ the thickness. So if you add an 18mm brace, add 12mm to the width.
dave
dave
I am really impressed with the kindness of the people in this forum, thanks for your help Dave. 🥲
So even if I used the type of bracing in the following image, would I still have to adhere 2/3 of width? Also using this type of bracing, would it be advisable if I used a vertical one plus the horizontal behind the driver?
I just want to follow the plan in the most detailed way possible, to get the most out of it..as i dont have any way to messure the results.. that's why I bother so much with questions and details, to get the finished speakers as close as possible to the original design. Again thanks for the time.
Also i would like to know if this plan is available for sale or its the complete enclosure that needs to be purchase directly from you guys:
As i´m seeing that looks smaller than the twin vent i ask about before, so in the future i can add a sub to the blend if needed, please let me know if there is a plan available as i´m in Colombia so shipping will cost more than the box+drives. 😒
Thanks a lot for the help and for the amazing job you guys are doing with the enclosure designs... 🔥💪
So even if I used the type of bracing in the following image, would I still have to adhere 2/3 of width? Also using this type of bracing, would it be advisable if I used a vertical one plus the horizontal behind the driver?
I just want to follow the plan in the most detailed way possible, to get the most out of it..as i dont have any way to messure the results.. that's why I bother so much with questions and details, to get the finished speakers as close as possible to the original design. Again thanks for the time.
Also i would like to know if this plan is available for sale or its the complete enclosure that needs to be purchase directly from you guys:
As i´m seeing that looks smaller than the twin vent i ask about before, so in the future i can add a sub to the blend if needed, please let me know if there is a plan available as i´m in Colombia so shipping will cost more than the box+drives. 😒
Thanks a lot for the help and for the amazing job you guys are doing with the enclosure designs... 🔥💪
The bracing in the translam is totally ineffective, it only braces the lam that it is a part of. Translam is also very wasteful. I have yet to see anyone fit a proper brace to a translam.
The 2nd is either mine or a copy of my bracing scheme for the milliSize box. Here is an early visualization on the top and the 1v1 version on the bottom. This brace breaks one of my primary bracing rule, but i really needed to brace the sides. The first builds showed this to be inadequate so we added the one from baffle to back just on top of the vent shelf.
Taking it to overkill one would do a vertical holey driver brace and then 4 stubs imitating a side to side one (open right behind the driver).
Rule 1 of bracing (and the one i broke): The subpanels created by a brace should have higher aspect ratios than the panel that is braced.
Rule 2: The subpanels should have dissimilar aspect ratios… don’t put it dead centre.
Rule 3: Tieing all 4 sides together is desirable (ceates an i-beam)
https://frugal-phile.com/boxlib/P10free/CGR-dCHR-Ken-301113.pdf
The wide one has good bracing, the narrow could really use some side to side stubs.
dave
The 2nd is either mine or a copy of my bracing scheme for the milliSize box. Here is an early visualization on the top and the 1v1 version on the bottom. This brace breaks one of my primary bracing rule, but i really needed to brace the sides. The first builds showed this to be inadequate so we added the one from baffle to back just on top of the vent shelf.
Taking it to overkill one would do a vertical holey driver brace and then 4 stubs imitating a side to side one (open right behind the driver).
Rule 1 of bracing (and the one i broke): The subpanels created by a brace should have higher aspect ratios than the panel that is braced.
Rule 2: The subpanels should have dissimilar aspect ratios… don’t put it dead centre.
Rule 3: Tieing all 4 sides together is desirable (ceates an i-beam)
https://frugal-phile.com/boxlib/P10free/CGR-dCHR-Ken-301113.pdf
The wide one has good bracing, the narrow could really use some side to side stubs.
dave
For reference, the Fenlon box is tuned to 50Hz or thereabouts, on a nominally flat alignment, which given the driver Q means it's peaking around 2.5dB at tuning with a similar F3 to the twin-duct design.
Thanks for sharing and time to look for it Scott 👍
I´m getting plans from Dave/planet10hifi 😎 To breathe easy beacuse my obsessive mind runs out of questions or doubts to answer and know that everything will be as perfect as possible with the budget to make it...i live in South America after all...but again making the most of it.
Thanks a lot guys! 🍻 i will post the finish speakers asap ⏭️
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Nice work Colombiangold, enjoy! 🙂
What amp and source are you using with these speakers? If I may ask, what type of music?
What amp and source are you using with these speakers? If I may ask, what type of music?
Fosi audio v3 + meanwell 24v 5amp..so 30w at 8ohm
DAC it's a ess9281 USB-C dongle to 3.5mm straight from computer.
Music..well, to give you an idea...just a short artist list + some examples songs:
Porcupine tree --- .3
Sade --- Jezebel (live)
Massive attack ---- black milk
Hermanos Rodríguez --- tres hermanos
Soda stereo ---- Angel eléctrico MTV unplugged
This it's my first speaker build and I'm just hook up..
I cannot choose a better box for nearfield listen..i was thinking and even get a tangband 5 ¼ subwoofer but after trying a little bit I realized it's not needed for my application/room size....planet10 designs + mark audio drivers literally rocks!
super recommended
DAC it's a ess9281 USB-C dongle to 3.5mm straight from computer.
Music..well, to give you an idea...just a short artist list + some examples songs:
Porcupine tree --- .3
Sade --- Jezebel (live)
Massive attack ---- black milk
Hermanos Rodríguez --- tres hermanos
Soda stereo ---- Angel eléctrico MTV unplugged
This it's my first speaker build and I'm just hook up..
I cannot choose a better box for nearfield listen..i was thinking and even get a tangband 5 ¼ subwoofer but after trying a little bit I realized it's not needed for my application/room size....planet10 designs + mark audio drivers literally rocks!
super recommendedGood to hear that you are finding your first DIY speaker build to your liking. 🙂
now i need to change my headphones as they not sound that good any more... its amazing to understand by experience all the concepts about speakers..lets say sound on and off axis how much it affects the general soound, the efects of croosover/bsc (i just get one connected to positive outside), room theatment..
Im not so sure yet but i already felt that the bsc takes some of the clarity? precision of the sound?..yes the give you more bass..at least at the moment thats my impresion with this drivers/box.. im also finishing a 2 way design to compare what can the same amount of money in drivers/parts for speakers can do. But until them i think i will be Single Drive/FR team..
Im not so sure yet but i already felt that the bsc takes some of the clarity? precision of the sound?..yes the give you more bass..at least at the moment thats my impresion with this drivers/box.. im also finishing a 2 way design to compare what can the same amount of money in drivers/parts for speakers can do. But until them i think i will be Single Drive/FR team..
