As recommended on that thread, the W5-1138 is a better compromise. I built a sub with this already and used a passive radiator made from a cheap speaker - cut the magnet off, add weight. The enclosure is 11 litres though. The 2053 is really only if you have to have a tiny enclosure of 3.5 litres or less. You can't have everything so if you want deep bass from a small box you have to sacrifice efficiency - hence people will say it's not very loud. Well, dur. And every coil heats up as it is fed more and more current. So. The issue really is that it will be driven hard because it has low efficiency. That's a given and its design addresses non-linearity at high excursions. Efficiency is 80dB per watt compared to a more normal 85dB ish for a similar sized cone. Overall, that means driving the sub at roughly 3x-10x the power you drive the satellites depending on their relative efficiency. So the 2053 is really only suitable for a low SPL (sound pressure level) 2.1 system. Say 10w to a pair of 1 litre satellites (perhaps using the 3"co-axials above - they model well in a sealed 1 litre enclosure) and 40W to the 3 litre sub. 50W rms amp for a 40W driver is about right.
My sub isn't pretty yet - still needs some work to tidy up its appearance
My sub isn't pretty yet - still needs some work to tidy up its appearance
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Hello
Thank you for your answer! Its really useful for me to know this.
I am gonna build an enclosure with 5-6 litres and I am really worry about W5-1138, may be it is to small enclosure for 1138. With simulations I have got around 50 Hz (with passive radiator) and I am wondering, by using active dsp (ADAU 1701) can I get lower bass for W5-1138 with this enclosure? will the use of an active DSP be justified in this case?
About SPL, W5-1138 has a sensitivity of 82 dB, but in real life W5-1138 is loader? And also better in other things?
The search for a passive radiator and its purchase is a big problem. Many are either not available and do not buy, or there are no characteristics
There is an opportunity to buy radiators from Dayton Audio SD215-PR 8 "but with a simulation of more bass I do not get, however using small Peerless by Tymphany 830878 3-1 / 2" the result on LF is better - it's strange for me
If you've decided the enclosure size but not the driver, then try Parts Express woofer selection guide. It gives volumes and frequencies among other data so you can find the driver that has the best compromise. Resources - Woofer Selection Guide
Based on Parts Express guide, I'd suggest Dayton Audio DS175-8 for a 0.2 cu ft sub capable of 40Hz. Dayton Audio DS175-8 6-1/2" Designer Series Woofer Speaker
So while I am going with an active crossover, I've decided to test a passive crossover as well. The speaker will have four binding posts... allowing for Linked Passive Crossover, Passive Bi-Amping, or Active Crossover.
So im still deciding on a Series or Passive crossover. Which of these responses look best? Im leaning toward the one with the highs attenuated as Im afraid the upper end will sound too fatiguing / loud. I'm trying to consider the loudness curve as well... my reasoning is attenuated highs should balance out with the lows due to human ears perceiving higher frequency sounds as being 'louder'. Thoughts?
So im still deciding on a Series or Passive crossover. Which of these responses look best? Im leaning toward the one with the highs attenuated as Im afraid the upper end will sound too fatiguing / loud. I'm trying to consider the loudness curve as well... my reasoning is attenuated highs should balance out with the lows due to human ears perceiving higher frequency sounds as being 'louder'. Thoughts?
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It's very subjective - some people prefer warm to clear and vice versa. What most people agree on (except someone now to disagree) is that sharp peaks in output are more noticeable than troughs. So, the curve on the left has a strong peak at 1.8kHz - shouty/forward/squeally vocals. The curve on the right might sound warm. Room interactions means you won't get either performance anyway, especially below 350Hz.
Have you got all the parts yet? Build it and listen to different configurations? Don't forget to run the drivers continuously for a few days to loosen up the spider etc and break them in.
Have you got all the parts yet? Build it and listen to different configurations? Don't forget to run the drivers continuously for a few days to loosen up the spider etc and break them in.
A few days ago, just for fun really, I decided to build a "JBL beater" too - a battery powered, Bluetooth, bi-amped, mono, omnidirectional speaker.
So I've bought some bits:
The Bluetooth TPA3110 amp
The battery holder and charge controller:
The 4 " passive radiator
The 3" long throw woofer
The 2" mid-tweeter
The omnidirectional case for mid-tweeter
And the rest of it is hardware like pipes, pipe bends, mdf, epoxy putty, etc.
I replaced the squaky 2" driver with the more balanced Harman - paper cone, neomydium magnet, etc... And at the same time I lightly stuffed the cone with fibre fill. It's much better but nothing special. Acceptable is the word. That is left to break in. I also broke in the woofer and then tested its fs - seems to be about 120Hz, which seems a bit higher than I hoped bit quite normal. I haven't measured qts but the suspension is very stiff. Based on experience, I reckon 1.5 litres would suit it, but to manage size, I'll use 1.2 litres using a section of 4" underground pvc pipe.
So I've bought some bits:
The Bluetooth TPA3110 amp
An externally hosted image should be here but it was not working when we last tested it.
The battery holder and charge controller:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
The 4 " passive radiator
An externally hosted image should be here but it was not working when we last tested it.
The 3" long throw woofer
An externally hosted image should be here but it was not working when we last tested it.
The 2" mid-tweeter
An externally hosted image should be here but it was not working when we last tested it.
The omnidirectional case for mid-tweeter
An externally hosted image should be here but it was not working when we last tested it.
And the rest of it is hardware like pipes, pipe bends, mdf, epoxy putty, etc.
I replaced the squaky 2" driver with the more balanced Harman - paper cone, neomydium magnet, etc... And at the same time I lightly stuffed the cone with fibre fill. It's much better but nothing special. Acceptable is the word. That is left to break in. I also broke in the woofer and then tested its fs - seems to be about 120Hz, which seems a bit higher than I hoped bit quite normal. I haven't measured qts but the suspension is very stiff. Based on experience, I reckon 1.5 litres would suit it, but to manage size, I'll use 1.2 litres using a section of 4" underground pvc pipe.
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My rocket speaker is making slow progress but it is at last taking shape ... 4"x 12"...
An externally hosted image should be here but it was not working when we last tested it.
I think it looks a bit silly tbh but its supposed to be fun...so why not. Is 3D printing expensive? It would seem to be an easier solution than MDF for unconventional boxes. I made a 1" thick mdf tube for the W5 2053 from lots of rings, and it was a lot of work to smooth the rings into a decent cylinder. 3D printing would be so much easier. The inside was a major pain to do.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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I'll post the links to Taobao but I guess you don't have access to that so maybe AliExpress?
This is the woofer - the code on the back suggests it is a Samsung part - perhaps from their R1.
2.5??????????????????????-???
The same seller also has a 4", perhaps from the R5/R7
4????????-???
The same seller also has the Harmon 2" with neodymium magnet
????2???????-???
I also considered this JBL 4" woofer
4?JBL????? ???-???
And this Philips 2" neodymium
2??????????-???
This is the 4"passive radiator
https://item.taobao.com/item.htm?spm=a1z09.2.0.0.57322e8d4J1PmO&id=532029550839&_u=o10d5b0g1cae
The top cone with a built in USB powered amp and nasty 2"driver is here
https://detail.tmall.com/item.htm?i...u=o10d5b0g4ac3&sku_properties=5919063:6536025
This is the bluetooth dual TPA3110 remote control amp
https://item.taobao.com/item.htm?spm=a1z09.2.0.0.57322e8d4J1PmO&id=553435876716&_u=o10d5b0g15c7
Some 3.7V 2900mah 18x65 batteries
https://detail.tmall.com/item.htm?id=40111449489&spm=a1z09.2.0.0.57322e8d4J1PmO&_u=o10d5b0g06e9
A battery board
https://item.taobao.com/item.htm?spm=a1z09.2.0.0.57322e8d4J1PmO&id=559901200628&_u=o10d5b0gab67
A battery holder
https://item.taobao.com/item.htm?spm=a1z09.2.0.0.57322e8d4J1PmO&id=538946614813&_u=o10d5b0g7ab0
In total it's about 180RMB, or around US$30.
So far I've also used some cable, 4" industrial pipe, mdf, epoxy putty, a McDonalds straw to hide the wires inside, the back half of a bass reflex port, and self tapping screws.
The bass reflex tube is here
https://item.taobao.com/item.htm?spm=a1z09.2.0.0.57322e8d4J1PmO&id=20056952709&_u=o10d5b0g8bb6
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This Bluetooth board does not work - usually boots with nothing, sometimes as ssai 02, always refuses to pair. I've tried 3 phones and all my tricks. It's crap. Don't buy it. It's a shame cos it's almost ideal for this project and I haven't seen any the same.
So I'm considering purchasing a Topping TP-60 Amplifier for this project (If the project doesn't sound good... it wont be a complete waste since I have other speakers I can use it for). I was looking for a relatively small but powerful amplifier that can output mono as well. There are almost no relatively small amplifiers that offer the ability to mono-bridge and maintain a small form factor. The Dayton APA150 amp would do the job... but its bigger than something I would consier semi-portable. I also don't love its front profile (Square rather than rectangular).
Which brings me to the Topping TP-60 which seems like a great, compact amplifier with a decent amount of power. When operating only a single speaker (With the assumption 1 channel of this TP-60 amplifier puts out enough power) would the SAFE / appropriate way be to sum the signal prior to amplification by the TP-60 and then just drive 1 output channel on the Topping TP60. So basically 1 channel is just left open. To sort of provide a visual for what is going on... imagine you wanted to play sound through only 1 bookshelf speaker. You take an AUX cable (Left and Right), one end goes into your phone the other end plugs into an RCA 'Y' cable that combines the signal. You then plug the single RCA output of the 'Y' cable into either the Left or Right input on the TP-60. You then drive the 1 bookshelf speaker off the channel that you connected the 'Y' cable to.
I realize this is a pretty lack luster way of doing it, but would it work? Or would it be better to just purchase a small mono amplifier for when I do this. (If anyone has any recommendations, please post).
Which brings me to the Topping TP-60 which seems like a great, compact amplifier with a decent amount of power. When operating only a single speaker (With the assumption 1 channel of this TP-60 amplifier puts out enough power) would the SAFE / appropriate way be to sum the signal prior to amplification by the TP-60 and then just drive 1 output channel on the Topping TP60. So basically 1 channel is just left open. To sort of provide a visual for what is going on... imagine you wanted to play sound through only 1 bookshelf speaker. You take an AUX cable (Left and Right), one end goes into your phone the other end plugs into an RCA 'Y' cable that combines the signal. You then plug the single RCA output of the 'Y' cable into either the Left or Right input on the TP-60. You then drive the 1 bookshelf speaker off the channel that you connected the 'Y' cable to.
I realize this is a pretty lack luster way of doing it, but would it work? Or would it be better to just purchase a small mono amplifier for when I do this. (If anyone has any recommendations, please post).
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TP60 is a TA2022 based amp? The Tripath TK2050 sound better, as do TI's TPA3251 and TPA3255. If you don't mind physically larger, some of the LM3886 amps can sound great too. If you want a mono amp, then TPA3116 /TPA3118 are available as PBTL (mono), not to be confused with BTL (stereo).
Every amp can be mono - double mono offers stereo so you can just leave one channel unused, as you suggest. If I were doing this, I'd short the input of the unused channel so the amp doesn't try to amplify any EMI or whatever into it's output filter with no load. I doubt it would harm a class D amp if you didn't but some can get funky.
What is your source for the amp? Is this source shared with anything else? If it is industry standard and not connected to anything else, then you can probably simply connect left and right together to create mono. If you think it might not be, or it is a headphone output, or...? ...then add 100R 1/4W resistors each on the the left and right signals and tie the other end of resistors together to create a mono signal.
If your source is connected to other gear and you need to maintain stereo, then you'll need a mixer - google virtual earth mixer and read up on that to get a better idea.
Every amp can be mono - double mono offers stereo so you can just leave one channel unused, as you suggest. If I were doing this, I'd short the input of the unused channel so the amp doesn't try to amplify any EMI or whatever into it's output filter with no load. I doubt it would harm a class D amp if you didn't but some can get funky.
What is your source for the amp? Is this source shared with anything else? If it is industry standard and not connected to anything else, then you can probably simply connect left and right together to create mono. If you think it might not be, or it is a headphone output, or...? ...then add 100R 1/4W resistors each on the the left and right signals and tie the other end of resistors together to create a mono signal.
If your source is connected to other gear and you need to maintain stereo, then you'll need a mixer - google virtual earth mixer and read up on that to get a better idea.
What would be the best way to short the input to an amplifier? Tie a wire from the unused input to the chassis of the amp (Ground)?
The source will be one of the following... Bluetooth to RCA module, laptop AUX, phone AUX, or a DAC like the schitt MODI. So it's industry standard as you suggested and not connected to anything else.
Just to be sure. There is no way to somehow tie the OUTPUTS of the amp together, correct? (even if it doesn't double the power). Much better to combine the signal before the amplifier right?
The source will be one of the following... Bluetooth to RCA module, laptop AUX, phone AUX, or a DAC like the schitt MODI. So it's industry standard as you suggested and not connected to anything else.
Just to be sure. There is no way to somehow tie the OUTPUTS of the amp together, correct? (even if it doesn't double the power). Much better to combine the signal before the amplifier right?
Seems like you'll be fine with a two-female-into-one-male RCA adapter.
To short an RCA input, get an unused RCA plug and short it's connectors, so it just looks like a plug with no cable - tidy. Or failing that, an uglier hack is to cut one off a cheap cable and tie the positive and ground together. To see if you need it, measure the DC and AC on the unused amp channel output while the other is in use. Check temperatures, especially the chip and the output filter inductors. If the readings are low mV, and there's no difference in the temperatures of all the inductors, and the chip isn't burning hot, it's fine. If the unused channel's inductors are hotter then your amp is going funky with no signal/load. I've never had this happen but others have reported it, esp when giving the channel a signal and no load.
It is possible to parallel amp outputs if the chip is designed for it and that configuration is already implemented in the design, eg TPA3116 PBTL. However, this gives no more voltage swing, only current, so it only allows a lower impedance speaker. With the same 8 ohm speaker, it adds no power. So it's somewhat pointless unless designed for it, but will but quickly kill the amp if it's not designed in. So yes, don't tie the outputs together - most class D are running BTL already so it's not possible. It's only if, as in rare cases, a class D amp is running single ended that it can be converted to BTL, but BTL is not parallel - it's two outputs in series running inverted signals - a push pull thing.
To short an RCA input, get an unused RCA plug and short it's connectors, so it just looks like a plug with no cable - tidy. Or failing that, an uglier hack is to cut one off a cheap cable and tie the positive and ground together. To see if you need it, measure the DC and AC on the unused amp channel output while the other is in use. Check temperatures, especially the chip and the output filter inductors. If the readings are low mV, and there's no difference in the temperatures of all the inductors, and the chip isn't burning hot, it's fine. If the unused channel's inductors are hotter then your amp is going funky with no signal/load. I've never had this happen but others have reported it, esp when giving the channel a signal and no load.
It is possible to parallel amp outputs if the chip is designed for it and that configuration is already implemented in the design, eg TPA3116 PBTL. However, this gives no more voltage swing, only current, so it only allows a lower impedance speaker. With the same 8 ohm speaker, it adds no power. So it's somewhat pointless unless designed for it, but will but quickly kill the amp if it's not designed in. So yes, don't tie the outputs together - most class D are running BTL already so it's not possible. It's only if, as in rare cases, a class D amp is running single ended that it can be converted to BTL, but BTL is not parallel - it's two outputs in series running inverted signals - a push pull thing.
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Thanks for the information Nanoloop. If I end up going with the Topping TP-60 or the Emotiva A-100 BasX, I'll definitely do that. I just discovered the BK Pear Drop Stereo Amplifier... seems relatively small, compact and provides the ability the bridge. I'm checking to see if they will ship one to the US... its a bit pricey, but seems worth it since I dont necessarily want to build my own amp. Slightly scared with going with the TP-60 since there seems to be some horror stories.
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