Hello to everyone,
I've been reading here and found many threads but I think that my project is a bit different so I would like to have your expert suggestions.
As per the title, this box will serve for a Opera singer for small audiences so it has to be portable, cost effective, and with a reasonable good audio quality.
I got some ideas and I know they might be 100% wrong so please bare with me and guide me to take the right decision.
The box internal sizes, approximately WxDxH 350mm x 200mm x 350mm.
A pair of quality 160mm coaxial car speakers to be installed to the sides of the box.
I don't need a 1,000,000,000..... Watts power speakers but efficient and with good audio quality.
I choose these kind of speakers so to save space and to make the project simple.
The box has to be portable so it needs a battery plus it has to be able to connect to a standard power outlet.
A microphone input is a must or maybe a wireless one, but I worry about quality.
And now the core of the system: the amplifier, power, player and communication system.
I found this Nobsound Mini Bluetooth CSR8630 4.0 Digital Power Amplifier: Amazon.com: Nobsound® TPA3116+LM1036 Bluetooth 4.0 CSR8630 Audio Receiver Hifi Stereo power amplifier board 50W*2 DIY: Electronics
I also found many devices like Lepai which have all I need like power, card reader, bluetooth etc. etc., the problem is that they all came with class D or T amplifiers and I worry that for my project they are not suitable so I'm looking for something in class A/B.
What do you guys think? Please guide me.
I've been reading here and found many threads but I think that my project is a bit different so I would like to have your expert suggestions.
As per the title, this box will serve for a Opera singer for small audiences so it has to be portable, cost effective, and with a reasonable good audio quality.
I got some ideas and I know they might be 100% wrong so please bare with me and guide me to take the right decision.
The box internal sizes, approximately WxDxH 350mm x 200mm x 350mm.
A pair of quality 160mm coaxial car speakers to be installed to the sides of the box.
I don't need a 1,000,000,000..... Watts power speakers but efficient and with good audio quality.
I choose these kind of speakers so to save space and to make the project simple.
The box has to be portable so it needs a battery plus it has to be able to connect to a standard power outlet.
A microphone input is a must or maybe a wireless one, but I worry about quality.
And now the core of the system: the amplifier, power, player and communication system.
I found this Nobsound Mini Bluetooth CSR8630 4.0 Digital Power Amplifier: Amazon.com: Nobsound® TPA3116+LM1036 Bluetooth 4.0 CSR8630 Audio Receiver Hifi Stereo power amplifier board 50W*2 DIY: Electronics
I also found many devices like Lepai which have all I need like power, card reader, bluetooth etc. etc., the problem is that they all came with class D or T amplifiers and I worry that for my project they are not suitable so I'm looking for something in class A/B.
What do you guys think? Please guide me.
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Hi, for cost effective jobs and good quality maybe you're right, class A/B or B amplifiers might be better than D or T class amplifiers.
An old car head unit containing a stereo amplifier might work very well for your purpose. Just pick some Behringer mic-amp which is 12 V runnable.
Or if you're into "old units", pick the part of a pcb from an old combo which has a mic input and the amplifier associated ( pre-amplifier ).
There are also specifical amplifiers for P.A. use that run on 24 V and have mic input; those that I'm referring to are old units and often use autoformers at output to have some headroom.
Nowadays those units are sold in a form of baggage-tray so you just have to buy the wheeled box and plug the mic in !
An old car head unit containing a stereo amplifier might work very well for your purpose. Just pick some Behringer mic-amp which is 12 V runnable.
Or if you're into "old units", pick the part of a pcb from an old combo which has a mic input and the amplifier associated ( pre-amplifier ).
There are also specifical amplifiers for P.A. use that run on 24 V and have mic input; those that I'm referring to are old units and often use autoformers at output to have some headroom.
Nowadays those units are sold in a form of baggage-tray so you just have to buy the wheeled box and plug the mic in !
Where can I find this stuff?
I also have no chances to look at old and second hand stuff because I won't be able to put the things together so I need suggestions regarding where and what to buy.
I'd go to the store and try out a Peavey KB300 with a SM58 mike or headset equivalent. You'll know what to sound to try for that way, before you do all the work. I'm not suggesting a guitar or bass amp because they may not have the frequency response to reproduce your whole voice. The super-cardioid mike is important for not picking up audience noise or feedback from the speaker. That box plus a generic sine inverter might solve the battery problem. It might work on a modified sine inverter, you'd have to experiment.
As far as Behringer, they copyright their schematic diagrams and sue people that distribute them. So they make their money off the "authorized" repair shop. Peavey will support the do it yourselfer with schematics.
I find the best way to get speakers and amps is used bar band equipment. Usually there are issues like blown input resistors and overage power supply electrolytic caps , gappy pots and things. Else that I can get new Peavey or JBL speakers from tubesandmore.com in AZ. There are a million sources of poor Quality controlled import **** speakers, google will send you to a hundred retailers if you search for speakers. One pile of **** is as bad as another IMHO. I get good quality resistors, caps, transistors from farnell.com, which operates in Sydney.
The boom box craze is so old, the only sources I'm finding of them is the curb on garbage day. They have the two 6" speakers and the DC power supply, some have a line input already. You'd need to fit in a mike preamp board probably to make a dynamic mike work. One op amp, usually, and some power supply modification parts.
If you decide to straight build, an op amp plus a LM3886 or other IC amp might be more reliable than some class D or T module. Less likely to howl ultrasonically into the mike circuit, too. That nobsound thing seriously needs a grounded steel box, with ferrite chokes on the inputs and outputs, to keep all the RF inside the box. Only 1/3 the engineering has been done on that; packaging is key with RF generating parts. See the IC amp forum under amps.
A guitar amp box makes a nice starting point for do it yourself, but guitar amps need a tweeter added to the main driver, usually 8" to 12" for voice. Guitars don't have frequencies above 4000 hz much, voice does. You need a crossover to split the frequencies between the two speakers, also a farnell or parts express part. Guitar amp circuits are suspect- frequency limited, and frequently have a particular "sound" which modifies the input to give it "character". For voice you probably don't want that signature branded sound.
As far as Behringer, they copyright their schematic diagrams and sue people that distribute them. So they make their money off the "authorized" repair shop. Peavey will support the do it yourselfer with schematics.
I find the best way to get speakers and amps is used bar band equipment. Usually there are issues like blown input resistors and overage power supply electrolytic caps , gappy pots and things. Else that I can get new Peavey or JBL speakers from tubesandmore.com in AZ. There are a million sources of poor Quality controlled import **** speakers, google will send you to a hundred retailers if you search for speakers. One pile of **** is as bad as another IMHO. I get good quality resistors, caps, transistors from farnell.com, which operates in Sydney.
The boom box craze is so old, the only sources I'm finding of them is the curb on garbage day. They have the two 6" speakers and the DC power supply, some have a line input already. You'd need to fit in a mike preamp board probably to make a dynamic mike work. One op amp, usually, and some power supply modification parts.
If you decide to straight build, an op amp plus a LM3886 or other IC amp might be more reliable than some class D or T module. Less likely to howl ultrasonically into the mike circuit, too. That nobsound thing seriously needs a grounded steel box, with ferrite chokes on the inputs and outputs, to keep all the RF inside the box. Only 1/3 the engineering has been done on that; packaging is key with RF generating parts. See the IC amp forum under amps.
A guitar amp box makes a nice starting point for do it yourself, but guitar amps need a tweeter added to the main driver, usually 8" to 12" for voice. Guitars don't have frequencies above 4000 hz much, voice does. You need a crossover to split the frequencies between the two speakers, also a farnell or parts express part. Guitar amp circuits are suspect- frequency limited, and frequently have a particular "sound" which modifies the input to give it "character". For voice you probably don't want that signature branded sound.
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Because the project you're proposing will probably be 10dB (or more) short on what your voice can do. Seriously.
I'd recommend an 8-10" PA speaker (read: around 95dB @1w) and get at least 50w into it, with a compressor-limiter on the mic input to stop loud peaks from putting the amp into hard clipping. That should give you more volume than your voice alone has, but probably not by much.
Chris
I'd recommend an 8-10" PA speaker (read: around 95dB @1w) and get at least 50w into it, with a compressor-limiter on the mic input to stop loud peaks from putting the amp into hard clipping. That should give you more volume than your voice alone has, but probably not by much.
Chris
Any bias against class D can only come from inexperience. Certainly for portable installations, class D is to be preferred.
Otherwise, agree with those who warned you that an opera singer by itself is already much louder than the boom box you are considering.
Class D has not only light weight for portability, but also high efficiency for battery life.
However, others have mentioned this already: have you heard the person sing in your presence? Opera is a powerful voice projection, it is not crooning ballads. My niece is an opera singer, she is currently studying the craft in France and Germany, but when she was last in the states, we went to a recital she put on in a small venue. I sure could not imagine her needing a microphone, it was plenty loud. Such a petite girl, and so much sound comes out of her.
have you discussed this with the singer, and he/she feels the need for amplification? And by small groups, that implies fairly intimate surroundings. No one will strain to hear the natural voice if they are only 20-30 feet away. Opera singers in general are filling the house with their voice from the stage.
Richard Wagner didn't have any PA systems.
Your car speakers may be fine, but in my personal opinion, I don't think to car speakers when I think quality of sound. Especially when they are just little 6 inch speakers. I would be concerned that two small car speakers blowing out either side of a small box wouldn't be projecting to the audience anyway.
However, others have mentioned this already: have you heard the person sing in your presence? Opera is a powerful voice projection, it is not crooning ballads. My niece is an opera singer, she is currently studying the craft in France and Germany, but when she was last in the states, we went to a recital she put on in a small venue. I sure could not imagine her needing a microphone, it was plenty loud. Such a petite girl, and so much sound comes out of her.
have you discussed this with the singer, and he/she feels the need for amplification? And by small groups, that implies fairly intimate surroundings. No one will strain to hear the natural voice if they are only 20-30 feet away. Opera singers in general are filling the house with their voice from the stage.
Richard Wagner didn't have any PA systems.
Your car speakers may be fine, but in my personal opinion, I don't think to car speakers when I think quality of sound. Especially when they are just little 6 inch speakers. I would be concerned that two small car speakers blowing out either side of a small box wouldn't be projecting to the audience anyway.
I've read on these forums there are some very good knowledged people who understand how to deal with amplificators and speakers.
Now what is wrong here, people telling me their personal experience with family members and friends and trying to discourage me from making this stuff, really guys you are not encouraging!
Just forget the Opera thing, I gave some input in the first post, an example of an all in one board, speakers and what I need.
For all who want to share their life experience, I advise to go here: The Lounge - diyAudio
Now what is wrong here, people telling me their personal experience with family members and friends and trying to discourage me from making this stuff, really guys you are not encouraging!
Just forget the Opera thing, I gave some input in the first post, an example of an all in one board, speakers and what I need.
For all who want to share their life experience, I advise to go here: The Lounge - diyAudio
Everyone who was in a opera ones in his lifetime will tell you exactly the same - opera singer don't need amplification and loudspeaker, especially in front of a small audience.
For other singers, get quality microphone and active 10" loudspeaker, for example:
K10 Active Loudspeaker ? QSC
For other singers, get quality microphone and active 10" loudspeaker, for example:
K10 Active Loudspeaker ? QSC
Yeah, the constant harping on your huge volume is annoying. If I sang opera, (I have the pitch and diction), I couldn't be heard across the room with a one person crowd. I have very low volume. My voice can't be heard over my acoustic piano. I've done Gilbert & Sullivan chorus, where my ability to dance with a broom in a sailor suit was more appreciated than any sound I added to the ensemble. I'm more into R&R and standards, though. I'd need a headset mike and some PA equipment too to sing with my piano or organ (see my signature, I've bought it all but the mike).
If you buy an 8" or 10" speaker only, your esses and tees will sound like a transistor radio. No high frequencies. Try it with a guitar amp in a pawn shop, see what I mean.
Those consonants have high frequencies. There are whizzer cone speaker that can do most frequencies with one driver, but the box is a special design. See under speaker construction, some kind of a one driver box. An LM3886 IC amp stuffed in that box would do the job. A digital amp would too, but you need to supress the RF howl with internal steel boxes and chokes etc like I said - leaving one of those out in the open just pollutes the whole world. You don't need more than about 50-70 watts though
Since you live in Oz, not going to quote vendors to you, except parts from farnell. Trans pacific shipping is outrageous. Farnell does have "sample" kit boards, including the TI demonstrator board that nobby amp was copied from. Your best board sources are probably going to be HK/Guangjou, but I don't read the language to sort out the alibaba links.
Really, go to the store (if in Sydney or Melborne) and hear yourself on a KB300, then don't settle for less accurate sound. Sounding like a transistor radio annoys me everywhere, especially at church where the whole visual/audio committee has no taste. Their piano and organ PA sounds like ****.
If you buy an 8" or 10" speaker only, your esses and tees will sound like a transistor radio. No high frequencies. Try it with a guitar amp in a pawn shop, see what I mean.
Those consonants have high frequencies. There are whizzer cone speaker that can do most frequencies with one driver, but the box is a special design. See under speaker construction, some kind of a one driver box. An LM3886 IC amp stuffed in that box would do the job. A digital amp would too, but you need to supress the RF howl with internal steel boxes and chokes etc like I said - leaving one of those out in the open just pollutes the whole world. You don't need more than about 50-70 watts though
Since you live in Oz, not going to quote vendors to you, except parts from farnell. Trans pacific shipping is outrageous. Farnell does have "sample" kit boards, including the TI demonstrator board that nobby amp was copied from. Your best board sources are probably going to be HK/Guangjou, but I don't read the language to sort out the alibaba links.
Really, go to the store (if in Sydney or Melborne) and hear yourself on a KB300, then don't settle for less accurate sound. Sounding like a transistor radio annoys me everywhere, especially at church where the whole visual/audio committee has no taste. Their piano and organ PA sounds like ****.
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There's nothing wrong about it. The thing you proposed simply isn't fit for purpose, and neither is anything similar. We're trying to ensure you don't waste your time and money. Its as simple as that.
If you want to DIY this, grab a 2-channel bridgable car amplifier, and a mixing desk that has a compressor built-in. You'll need 12v batteries and a low-power inverter to power the mixing desk.
I've no idea which PA speakers are available to you, or what your budget is. I do know that some people near you are using B&C speakers, which are a good brand. I'd probably just get a 10" coaxial and call it good - that'll probably come with a crossover design already done, saving you from doing your own. Passive crossover design isn't easy.
Mic goes into desk with compression set appropriately, then desk to amp that's bridged into the speaker on a high-up stand for maximum projection. Tune the cabinet in accordance with the Boominator thread for maximum apparent LF output.
Chris
Coaxial speaker is a modern name for the whizzer cone speaker I mentioned above. A second cone for higher frequency response.
AC inverter just for the mixer seems a waste. The op amps can get by using +-5 v on a dynamic mike input. Farnell consumer division sells velleman op amp kits here, maybe the main office in Sydney does it. Not very good kits, but okay to start with. Actually the dip project boards mcm sells (farnell consumer) a dip socket and one 4558 or 4580 IC should do it, plus a couple of caps and some resistors. Two zeners to estabilish the +-5 off the 12 v rail, some resistors to keep the zeners from blowing up, a pot - about $5 in parts.
I've blown off the whole compressor thing, but I don't like compressors. Not using one, you have to make sure the mike stays a constant distance from your mouth to get constant volume. The headset mike makes it easy, but millions have succeeded doing that using an SM58 dynamic mike.
BTW the KB300 has a mixer and frequency control built in, if you're going to be buying an inverter.
Best of luck.
No, he means built in coaxially mounted compression driver for the highs. If you buy the unit you don't have to build a crossover - there are combos avaialble that come with one specifically designed for those drivers. Of course you can just build a 10"/1" 2 way but you have to know what you're doing.
And no, 50 watts or less isn't going to be enough. Yes, it can be heard, but you'll end up driving it into heavy compression and/or heavy clipping to do so. If you're an auctioneer or rodeo announcer that's fine. If you want quality it's not. 500 watts is about right - like that QSC that was suggested. It's a really nice speaker. Can you build one as good? Yes and no. Certainly not with one of those little class D amp kits - none of them put out anywhere near advertised power. Can you build one? Yes, if you have knowledge and lots of accumulated parts inventory. You go to price everything out and you may as well just order the QSC.
No, coaxial speaker is actually two (or three) speakers in one. Coaxial tweeter is mounted in the center (on axis), in front of or behind the midbass cone. Both centers (of the midbass and tweeter) are laying in the same axis - co-axial.
Range of single full-range loudspeakers called dual cone have a small whizzer cone.
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