While in my long quarantine during this Covid-19 crisis, I have so much time so I decided to built a desktop speakers for my PC. After reading numerous thread and positive comments, I plan to use MarkAudio CHR-70.3 as it fits my budget.
I know there are a lot of proven cabinet design with the CHR-70 but they are just too big to fit my desktop. So I plan to built one that have small footprint but tall like a mini tower. I'm thinking of using the design below:
So I came up with a design that is 16x16x33(w,d,h). Basically its a tall square tower.
The volume excluding the port is 4.56L and I got the box tune at 42hz and gives a 1cmx42cm port at the bottom.
I am not sure if i have done everything correctly. Is a square tower a good for speaker box? The goal is to built a good sounding desktop speaker with good bass output. I know it's impossible to achieve punchy bass with a 4" fullrange driver but at least it should not sound thin without bass at all. Or are there better driver for this task beside the CHR-70?
I know there are a lot of proven cabinet design with the CHR-70 but they are just too big to fit my desktop. So I plan to built one that have small footprint but tall like a mini tower. I'm thinking of using the design below:
So I came up with a design that is 16x16x33(w,d,h). Basically its a tall square tower.
An externally hosted image should be here but it was not working when we last tested it.
The volume excluding the port is 4.56L and I got the box tune at 42hz and gives a 1cmx42cm port at the bottom.
An externally hosted image should be here but it was not working when we last tested it.
I am not sure if i have done everything correctly. Is a square tower a good for speaker box? The goal is to built a good sounding desktop speaker with good bass output. I know it's impossible to achieve punchy bass with a 4" fullrange driver but at least it should not sound thin without bass at all. Or are there better driver for this task beside the CHR-70?
The box is to small, i would not put this driver in a vented box below 8L you also tune it way to low for this driver, 50Hz is the lowest i would try (or it has to be a TL). And a small box will always be a compromise. This is the best i could get out of it (on the published specs) with this driver and your goals and compromises you want to take...
And no, a square tower is never a good id, it makes that one frequency wil resonate more. So make it deeper or wider.
PS: port size is set so the velocity is below 17 at full power (20w) to avoid port noise.
And no, a square tower is never a good id, it makes that one frequency wil resonate more. So make it deeper or wider.
PS: port size is set so the velocity is below 17 at full power (20w) to avoid port noise.
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Thanks waxx. 10 liter is too big for my desktop. Good thing I haven't order it yet. I might have to continue searching for small diy speaker. What do you think of the scottsehlin Helium?
You try to do the impossible, getting bass out of a micro speaker. I think you need to revision your id, and maybe go with some small sealed on your destop and a sub below. Otherwise you will never have bass.
That Helium i don't know, but when i read the specs, there is not much output below 100hz, and the curve starts going down even before. You can do the same with that CHR70 in a 5L sealed box, and both will need a sub below your desk with a cr arround 100Hz to get real bass. The CHR-70 in a sealed 5L enclosure will be cheaper and easier to build. in 12mm plywood it would be something like 15cm wide, 25high and 20 deep (to give an id)
That Helium i don't know, but when i read the specs, there is not much output below 100hz, and the curve starts going down even before. You can do the same with that CHR70 in a 5L sealed box, and both will need a sub below your desk with a cr arround 100Hz to get real bass. The CHR-70 in a sealed 5L enclosure will be cheaper and easier to build. in 12mm plywood it would be something like 15cm wide, 25high and 20 deep (to give an id)
LOL. I got overly optimistic about the superbass. I check the Helium and the bass is output looks similar. I did play around with a round port(2cm x 6cm long) tune to 50 hz.
Is this response any better? Let say its for nearfield where the speaker will be about 2 ft from the ear. What I really want is is clear detail sound that is balanced with a decent bass. I am not expecting chest pounding or heavy bass. I choose the CHR-70 because I saw many good reviews in much larger build. Will the CHR-70 bring much improvement from those cheap PC speakers in $100 range?
An externally hosted image should be here but it was not working when we last tested it.
Is this response any better? Let say its for nearfield where the speaker will be about 2 ft from the ear. What I really want is is clear detail sound that is balanced with a decent bass. I am not expecting chest pounding or heavy bass. I choose the CHR-70 because I saw many good reviews in much larger build. Will the CHR-70 bring much improvement from those cheap PC speakers in $100 range?
Technically yes, but it still really needs a larger box, unless you run it sealed. You may be surprised at the impression of LF you get from a sealed box, especially in the nearfield.
One option (depends if you can stretch to it & find a stockist): Alpair 6.2 (Alpair 6M). Often overlooked, so it's never got much coverage, but it's a nice little driver that does well in about 5 litres, vented, Fb in the mid 50s.
One option (depends if you can stretch to it & find a stockist): Alpair 6.2 (Alpair 6M). Often overlooked, so it's never got much coverage, but it's a nice little driver that does well in about 5 litres, vented, Fb in the mid 50s.
You try to tune this speaker below it's possibilities, and it will sound bad. I made that mistake also in the past. This driver in this box will sound boomy because the box is too small and you tune it to low for that box. What you try to do with this driver is impossible. Then better follow Scottmoose's advice and try to find that 6.2 driver that is more fit for this kind of super small ported speakers.
I looked at this and the vent looks too long, but the sims look OK. The high ratio vent will reduce the peaking just before roll-off.
Except for the strange vent length, it is much the same volume as the mCHR-Ken (4.7 litre), but the tunign number (IIRC is lower).
A larger box (a full-size miniOnken is 9L) but i have always found the CHR70 to sound bass shy.
What is yur driver budget?
dave
Except for the strange vent length, it is much the same volume as the mCHR-Ken (4.7 litre), but the tunign number (IIRC is lower).
A larger box (a full-size miniOnken is 9L) but i have always found the CHR70 to sound bass shy.
What is yur driver budget?
dave
Just FWIW, if you're running a desktop system with a PC as a source, you can use EQ APO to provide some EQ adjustment.
I've been using this route for a while, and have found the results excellent. My latest desktop speakers are actually just a pair of Kef eggs with some EQ to bring up the low bass.
IMO, it's a good way of getting lots of LF extension from a small box when outright SPL isn't a concern.
Chris
I've been using this route for a while, and have found the results excellent. My latest desktop speakers are actually just a pair of Kef eggs with some EQ to bring up the low bass.
IMO, it's a good way of getting lots of LF extension from a small box when outright SPL isn't a concern.
Chris
Hi Dave. After reading somewhere that long port would induce noise and losses, I redesign the cabinet with round port.
An externally hosted image should be here but it was not working when we last tested it.
Like waxx said, the design will sound boomy because its too small and I tune it to low for that box.
The budget for the driver is somewhere from $30-$40.
That is the general wisdome, but all off my miniOnken design suse it to good effect. I avoid tubular vents if i can. at least in BRs.
More volume does not hurt as long as you don’t make it too big.
What other brands of drivers can you access easily?
dave