Hello everyone
I've been given an old iPod bedside speaker (remember those?) and since it was not wireless, and I don't have an iPod, I pullet it apart. I would discuss about the electronics in it, but that's a post for another forum, so keep an eye out on that. What I am here for is for some general advice. The thing is, I ran these speaker drivers, which I have yet to mention are the Swan/HiVi C3N. They look fairly well, paper cone and rubber surround with a shielded magnet. I pulled up a spec sheet I found online for them and ran the parameters through a calculation software, in this case WinISD. For some reason, I tried 3 different enclosure types, for instance, I used sealed, ported, and passive radiator. The only problem is that for no matter what I do, I cannot get the -3 below 120hz. I listened to them in the old enclosure which was ported, and the highs werent "sparkly" but that's to be expected because they roll off at about 15k and there were no tweeters. I say the bass was pretty decent, perhaps around the 80db range at -3db. I have used WinISD many times in the past for various projects so I can admit it is not user error. I am thinking of using a passive radiator design, as well as some simple crossovers with maybe one or two tweeters. The usable volume of the enclosure I am going to make is around 0.1 cubic feet, which is the USABLE space. The enclosure is bigger, but since it is portable things such as batteries and electronics take up some space. I was planning on using passive radiator(s) as they are notorious for small enclosure where a conventional port is not viable. Take for example the Bose soundlink mini. I like it, other may not, but for what it is, and all the tech they jammed into it, it's a great background music speaker. I have a friend who has one and we measure an approximate bass response of about mid 70's at minus 3 decibels, which is fine for what I'm doing, though lower is of course better. Not to mention my design is much bigger at 0.1 cubic feet vs 0.5 liters for the soundlink mini. Any suggestions? Thanks guys.
Also, I can list the parameters if anyone is interested, or cannot find them.
I've been given an old iPod bedside speaker (remember those?) and since it was not wireless, and I don't have an iPod, I pullet it apart. I would discuss about the electronics in it, but that's a post for another forum, so keep an eye out on that. What I am here for is for some general advice. The thing is, I ran these speaker drivers, which I have yet to mention are the Swan/HiVi C3N. They look fairly well, paper cone and rubber surround with a shielded magnet. I pulled up a spec sheet I found online for them and ran the parameters through a calculation software, in this case WinISD. For some reason, I tried 3 different enclosure types, for instance, I used sealed, ported, and passive radiator. The only problem is that for no matter what I do, I cannot get the -3 below 120hz. I listened to them in the old enclosure which was ported, and the highs werent "sparkly" but that's to be expected because they roll off at about 15k and there were no tweeters. I say the bass was pretty decent, perhaps around the 80db range at -3db. I have used WinISD many times in the past for various projects so I can admit it is not user error. I am thinking of using a passive radiator design, as well as some simple crossovers with maybe one or two tweeters. The usable volume of the enclosure I am going to make is around 0.1 cubic feet, which is the USABLE space. The enclosure is bigger, but since it is portable things such as batteries and electronics take up some space. I was planning on using passive radiator(s) as they are notorious for small enclosure where a conventional port is not viable. Take for example the Bose soundlink mini. I like it, other may not, but for what it is, and all the tech they jammed into it, it's a great background music speaker. I have a friend who has one and we measure an approximate bass response of about mid 70's at minus 3 decibels, which is fine for what I'm doing, though lower is of course better. Not to mention my design is much bigger at 0.1 cubic feet vs 0.5 liters for the soundlink mini. Any suggestions? Thanks guys.
Also, I can list the parameters if anyone is interested, or cannot find them.
Did you do the necessary maths to check if your parameters are correct? They could be wrong.
It's also very possible that the speaker box they were originally in didn't do that much better, but the driver board did a lot of DSP.
It's also very possible that the speaker box they were originally in didn't do that much better, but the driver board did a lot of DSP.
The parameters are correct, I checked about 3 times, unless there were typo's in the datasheet.
I pulled the board and inspected it as well. The only smart functionality of the board was the onboard 8 bit micro controller which does not have nearly as much power needed to run computations such as DSP. The micro controller was likely used for button input and D/A conversion from the iPod connector.
It's a 3" driver with a Fs of 130 Hz, a Qts of .96, and a 2.5 mm Xmax...so in a sealed enclosure you won't get anything lower than about 150 Hz at best, with a reflex you might be able to get it down to 70 Hz, but that's really pushing it to extremes, and a passive assist will fall somewhere in between. If you want lower/louder bass, you need a different driver.
Mike
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I was thinking to buy a bulk amount of those cheep eBay passive radiators. They go for around a dollar to two. I was thinking of buying a total of 10 consisting of various sizes to see which one(s) perform the best with HiVi's. What do you all think?
You posted your findings on the the drivers you have at hand.
It appears you would like a deeper bass response.
Some have made suggestions and observations as to what is possible with what you have.
It appears you would still like a deeper bass response than what the drivers can deliver.
My suggestion based on this is you might be better served finding a different driver that can deliver the bass level you would like.
It appears you would like a deeper bass response.
Some have made suggestions and observations as to what is possible with what you have.
It appears you would still like a deeper bass response than what the drivers can deliver.
My suggestion based on this is you might be better served finding a different driver that can deliver the bass level you would like.
Thanks for the suggestion. I’ll experiment by making prototype enclosures with this driver using all of you guys suggestions, and then if it still does not meet the criteria then I will find other drivers. I will post my results once I get the boxes built and speakers operational. Thanks guys
To save you money, maybe try a stiff cardboard box with another bit rolled up for the port ?
Obviously not an ideal long term solution.
And it will obviously change how it sounds compared to a 'proper' wooden box.
But it might help you to work out if this is the right direction for you.
Obviously not an ideal long term solution.
And it will obviously change how it sounds compared to a 'proper' wooden box.
But it might help you to work out if this is the right direction for you.