I mounted mine on a wall plate
Now I can put them on almost anything, wood, metal, plastic box. Even wall mount, or I might put then in speaker stands. They will fit a standard electrical wall box or mount with 2 screws onto a chassis.
This looks really cool
I get it. Thanks!
So, I'm not trying so much to be able to recreate the thump from percussive bass guitar or a kick drum. I'm thinking more about nice-sounding sostenuto in the low guitar/cello/baritone voice range and on up. The 2.5" driver I'm looking at has Fs of about 70Hz. In WinISD, it looked like I could get a fairly flat response down to 65-70Hz from this driver in a 45c.i. ported box. (I think... It was a while ago that I did that simulation.) The only issue being that it is not a loud driver at all.
I'm hoping this will make for a pleasant and more natural-sounding (though not loud) portable speaker. I'm not trying to build a "party in my pocket" kind of speaker... If that makes any sense at all. If I'm barking up the wrong tree I'd be happy to hear about it now, before I start buying parts and building. I appreciate the input.
Also, sorry to be going off topic. I've had another thread going in the "construction tips" forum in which I asked for some advice for this build, but posted over here since I had a specific question that pertained directly to the "Sanwu blue" 3118 board.
The CF is just vinyl CF "look" that I wrapped on them. I did some switch plates as well. BTW/ the the plates I used for the amps are from Parts Express. They cost $.29 each and have a pair of very good quality RCA jacks on each plate. I get them for the RCA's This is the first time I have actually used the plates though.
Link:
RCA Wall Plate with F Connector & 2 RCA Jacks
Clengman,
If you are not opposed to a slightly bigger box, try the 0.40x scale Karlsonator with a 3in Faital Pro 3FE25. 91dB and bass down to 70Hz with no baffles step loss. Sounds very good with great mids and highs and just enough bass to satisfy for most music. Make it out of foam core and it weighs nothing and is portable. Stick the 3118 inside and use a resistor network to combine stereo to mono.
Here is the speaker with a TC9FD which also works well but is only 85dB:
More info here:
http://www.diyaudio.com/forums/full-range/239338-mini-karlsonator-0-53x-dual-tc9fds.html
If you are not opposed to a slightly bigger box, try the 0.40x scale Karlsonator with a 3in Faital Pro 3FE25. 91dB and bass down to 70Hz with no baffles step loss. Sounds very good with great mids and highs and just enough bass to satisfy for most music. Make it out of foam core and it weighs nothing and is portable. Stick the 3118 inside and use a resistor network to combine stereo to mono.
Here is the speaker with a TC9FD which also works well but is only 85dB:
More info here:
http://www.diyaudio.com/forums/full-range/239338-mini-karlsonator-0-53x-dual-tc9fds.html
xrk971 - I've been curious about these Karlsonator speakers since I started reading on the forum here. I think I'll definitely try it sometime. What reason is there not to? 
It's not really the form factor I'm going for this time, though. Small size is a major priority for this one. I want to be able to take it in my backpack on weekend camping trips. The speaker enclosure will be around 3"x6"x2.5" with another small compartment on top for battery and amp.
It's not really the form factor I'm going for this time, though. Small size is a major priority for this one. I want to be able to take it in my backpack on weekend camping trips. The speaker enclosure will be around 3"x6"x2.5" with another small compartment on top for battery and amp.
Did anyone ever say what the gain setting for these little tpa3118 amps is? If the gain is set very high and you have very efficient speakers, some hiss might just be inevitable. So if you don't need the max volume these guys are capable of, you could lower the gain to possibly hide the hiss. Although given their size, changing the gain resistors might require some micro-surgery.
The reading I've been doing lately suggests that many hums/hisses are caused by grounding problems. What kind of power supply are you using? And have you tried any others?
Oh, another hack I've seen from time to time: put a resistor between leads on your RCA. Maybe something like 100k ohm between RCA positive and ground.
i don't think it matters but they inverted the input, so it seems. Outputfilter you could measure but might be inductor plus snubber and 1nF, and miss the 680nF, 680nF position looks vacant to me as if forgotten, makes funny filter, like TI filterless FB filter maybe??
Input wires are not really twisted and crossing powerwires and gainsetting, is it 36dB standard? I think the 3116 version is 36dB ? I can blow up, zoom board but resolution photo is a little too small to see gainresistor values That would be main reason for hiss I guess, although I don't know if filter helps
edit: shoot forgot to write first thought: jumper gnd to positive input if there isn't a jumper already, the input not used now, has same effect as dugs/marsh amps without gnd, one input must be grounded and it isn't, pcb is both for differential inputs and single ended.
Input wires are not really twisted and crossing powerwires and gainsetting, is it 36dB standard? I think the 3116 version is 36dB ? I can blow up, zoom board but resolution photo is a little too small to see gainresistor values
That would be main reason for hiss I guess, although I don't know if filter helpsedit: shoot forgot to write first thought: jumper gnd to positive input if there isn't a jumper already, the input not used now, has same effect as dugs/marsh amps without gnd, one input must be grounded and it isn't, pcb is both for differential inputs and single ended.
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Thanks for you answers.
I will take a sharper photo of the board. I have tried them with a 12/12V meanwell smps and a 19V laptop brick and with 2 different pair of speakers one being incomplete TB W3 TABQ.
I don’t hear any hiss while playing music from normal sitting distance across the room but within a meter or so at low volume it is quite noticeable.
I will take a sharper photo of the board. I have tried them with a 12/12V meanwell smps and a 19V laptop brick and with 2 different pair of speakers one being incomplete TB W3 TABQ.
I don’t hear any hiss while playing music from normal sitting distance across the room but within a meter or so at low volume it is quite noticeable.
That's a good question. I'm planning to get one of these and I was assuming it is single ended, but now that you mention it, I don't know.
If it's differential and I'm using sources that are single ended, does it matter?
pin4 RINP goes to c12 and then to connector far right, silkscreen label -
pin5 RINN goes to c13 and then to connector where you connected centerpin cinch and further to connector far right, silkscreen label +
The unused input needs to be connected to gnd.
Sanwu is single ended, capacitor on negative input is grounded.
RightINPositive goes to silklabel -, RightINNegative goes to silklabel +, that is what I meant when writing inverted.
pin5 RINN goes to c13 and then to connector where you connected centerpin cinch and further to connector far right, silkscreen label +
The unused input needs to be connected to gnd.
Sanwu is single ended, capacitor on negative input is grounded.
RightINPositive goes to silklabel -, RightINNegative goes to silklabel +, that is what I meant when writing inverted.
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I have two Sanwu postage stamp amps, blue PCBs
Both are 32dB [39k & 100k resistors]
Haven't put my ears against speakers to listen for hiss; will do so later in the week. From 5m away, don't hear any
j.R.c
Thanks Nisbeth!
Hi, Thanks. I was gathering that BTL equals stereo and PBTL equals monoblock configuration.
Mark
Hi, Thanks. I was gathering that BTL equals stereo and PBTL equals monoblock configuration.
Mark
Thank you for the replies!
Looking at the TI schematic on the 2.1 amp and focusing on the PBTL ( "0.1" side ) set up, the input is basically the INPR and INNR (the differential input for the right channel when operate in stereo mode) and the left channel inputs INPL and INNL are shorted to GND.
For single end connection, the INNR (-ve link) is going to GND (probably connected on the PCB), I presume. Am I reading the schematic correctly?
If that's the case, there is no point in using a differential input unless disconnecting the "-ve" input connection from GND.
Regards,
Looking at the TI schematic on the 2.1 amp and focusing on the PBTL ( "0.1" side ) set up, the input is basically the INPR and INNR (the differential input for the right channel when operate in stereo mode) and the left channel inputs INPL and INNL are shorted to GND.
For single end connection, the INNR (-ve link) is going to GND (probably connected on the PCB), I presume. Am I reading the schematic correctly?
If that's the case, there is no point in using a differential input unless disconnecting the "-ve" input connection from GND.
Regards,