Hi guys, I just picked the speakers up today... It's a Sony hi-fi set, model HCD-GRX7. It comes with a pair of speakers (model no. SS-J75) impedance 8 ohms. On the back of the stereo it says "AC: 220-240V~50/60Hz 250W." The speakers each have one pretty bassy driver and 3 tweeters.
So what now? Remember this is all going into a recycled speaker box dimensions are 580x410x210. It will play anything with a 3.5mm auxillary jack and preferably have a volt gauge and a volume control, all powered by a 12v battery(or whatever other recommendation you have).
Cheers 😀
Jo
So what now? Remember this is all going into a recycled speaker box dimensions are 580x410x210. It will play anything with a 3.5mm auxillary jack and preferably have a volt gauge and a volume control, all powered by a 12v battery(or whatever other recommendation you have).
Cheers 😀
Jo
nice! you got something to get started. the first thing is to take apart those SS-J75 speakers to figure out how to mount the woofers and tweeters inside your recycled speaker box. pay attention to how all the wires are connected inside and there are probably a few other parts near the tweeter that works as a crossover. you will want to connect the speakers and crossover parts exactly as they were when they came out of the original box. The nice thing about the sony HCD-GRX7 is that I was able to easily find a service manual for it by searching around the web. I recommend that you look for it because it has alot of nice diagrams of all the parts inside. I browsed through the service manual briefly and found that the power amplifier is built onto a seperate circuit board and easily removed. unfortunately that model is not designed to work from a battery but it might work. maybe you will need 2 batteries because the circuit wants to have both a positive and negative voltage. also it looks like you can take out the headphone jack to use as the input to connect your ipod. I assume that you don't care about the CD player, cassette, and radio tuner so just put those aside. the headphone jack and the power amplifier boards will have wires and connectors attached to them, try to save those as you can re-use them when reconnecting the parts in your box. you will still need batteries but then that's enough parts to get going if you give up the battery meter and use the ipod volume control instead of adding a volume knob. you can also add those later once you have the first part going. here's a very simple diagram: (attached) the connectors and pin numbers correspond to what's shown in the service manual. I added the 22k resistor because the amplifier has an enable input that wants to be turned on by a controller on another board, this resistor takes the place of the controller board.
what does everybody think? the power connector on the amp is really meant to connect to a transformer secondary, and the voltage is supposed to be much higher, about +/- 43 volts. it goes right to a bridge rectifier so connecting DC battery to it shouldn't really be a problem. I'm hoping that the lower voltage wont be a big problem, just not as loud.
good luck!
-Joel
what does everybody think? the power connector on the amp is really meant to connect to a transformer secondary, and the voltage is supposed to be much higher, about +/- 43 volts. it goes right to a bridge rectifier so connecting DC battery to it shouldn't really be a problem. I'm hoping that the lower voltage wont be a big problem, just not as loud.
good luck!
-Joel
Attachments
Okay I have already taken the speakers apart, and the stereo unit but I think the reusing of the amp board IS NOT HAPPENING. Hahahah it's way too complicated and I don't know what I'm doing so I will just donate it to the second hand store...
So what amp and batteries would I be looking at getting? I think I want to remove the middle tweeter from each speaker as it is sorta damaged. Will that work? And how am I wiring these things up? I would put some pictures up but I don't know how to make it into a URL.
Jo
So what amp and batteries would I be looking at getting? I think I want to remove the middle tweeter from each speaker as it is sorta damaged. Will that work? And how am I wiring these things up? I would put some pictures up but I don't know how to make it into a URL.
Jo
amplifier
what about using something like this to keep things simple. it even has a diagram of where to connect the wires, you would need 2 one to drive the left channel and theother to drive the right channel.
18W Universal Amplifier Module : Audio Modules : Maplin
also it will use any dc voltage from 6v-20v.
hope that helps
cheers
what about using something like this to keep things simple. it even has a diagram of where to connect the wires, you would need 2 one to drive the left channel and theother to drive the right channel.
18W Universal Amplifier Module : Audio Modules : Maplin
also it will use any dc voltage from 6v-20v.
hope that helps
cheers
Hi Jo-Ann, welcome to the forums.
If you can get hold of some 24v batteries, consider something like this:
2*100w TK2050 TP2050 Tripath Class-D Audio Amplifier | eBay
You connect up the power supply, speakers and iPod and it'll make music.
Could you post a picture of the speakers you have? I can't find any reliable images on Google of what they may be.
Cheers,
Chris
If you can get hold of some 24v batteries, consider something like this:
2*100w TK2050 TP2050 Tripath Class-D Audio Amplifier | eBay
You connect up the power supply, speakers and iPod and it'll make music.
Could you post a picture of the speakers you have? I can't find any reliable images on Google of what they may be.
Cheers,
Chris
Parts Express has a video how to on hooking up the Sure amp boards. I think you will find it encouraging. Good luck
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Hello everyone,
Attached are the pictures of the speakers. The middle tweeter is sorta damaged on this one, but on the other one the paper cone(oh forgive me for not using the correct terms!) has a hole in it. I'm thinking of just removing both middle tweeters from the system but I'm not sure if it will work because it has a capacitor looking thing on it. If it won't work, could you please advice on how I should wire these up so it works?
Chris, what's the difference between 12V batteries and 24V? What's the difference between AC and DC? For this setup should I be looking at AC or DC?
So basically now all I need is just an amplifier and a battery? What main points should I be looking out for when choosing an amp and the batteries to give me the most efficient system possible? Bear in mind I plan to remove the middle tweeter from the speakers.
This is fantastic. We are getting somewhere - I never thought I could! Haha. I'd love to see the end result, I'm excited! 😀
Attached are the pictures of the speakers. The middle tweeter is sorta damaged on this one, but on the other one the paper cone(oh forgive me for not using the correct terms!) has a hole in it. I'm thinking of just removing both middle tweeters from the system but I'm not sure if it will work because it has a capacitor looking thing on it. If it won't work, could you please advice on how I should wire these up so it works?
Chris, what's the difference between 12V batteries and 24V? What's the difference between AC and DC? For this setup should I be looking at AC or DC?
So basically now all I need is just an amplifier and a battery? What main points should I be looking out for when choosing an amp and the batteries to give me the most efficient system possible? Bear in mind I plan to remove the middle tweeter from the speakers.
This is fantastic. We are getting somewhere - I never thought I could! Haha. I'd love to see the end result, I'm excited! 😀
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.
I don't know if the image links are working so here they are:
IMG_2400 | Flickr - Photo Sharing!
IMG_2403 | Flickr - Photo Sharing!
IMG_2400 | Flickr - Photo Sharing!
IMG_2403 | Flickr - Photo Sharing!
I did'nt look at entire thread, so apologies if someone already suggested this, but here's some good info for beginners, about half-way down the page.
DIY Audio Articles
Mike
DIY Audio Articles
Mike
Depending on how it's wired, you could probably just disconnect the middle one if you're unhappy using it in its damaged state. It will probably work okay.
My initial ideas for a boombox layout would be (from the inside outwards per side) Woofer, super tweeter (the little round one nearest the top), then a vertical line of the 3 midranges.
Make it symmetrical across the front and you're good to go.
I suppose you could put one of the mids on the top/side/back to widen dispersion...
Chris
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Jo-Ann, I haven't really followed this thread but I have built boomboxes (ghetto-blasters) recently. Does yours have to be battery operated or could it be just a portable that uses the mains?
Hi Cal, it has to be battery powered.
If anyone could show me a diagram of how to wire this up, it would be fantastic! :>
If anyone could show me a diagram of how to wire this up, it would be fantastic! :>
Jo in post#22 Joel gave you a diagram how to hook up the sony. If this wont work for you Chris in post #25 recomended an amp that is very easy to hook up. I followed up in post #26 these boards are made for beginners, they are plug and play, no soldering. Watch the video. Mike in post #29 recomended a good site for you to understand how this works. Follow up and let us know how we can help. Best Wishes.
Howie
Howie
Ok, I think I will go with the TK2050 amp. So all I need after getting this amp is a 24V SLA DC battery and I'm good to go?
According to the eBay page, yes: a single 24V battery will be fine.
Just remember that, at full output (which will be loud), the amplifier will be taking about 10A. This is a lot: a 5Ah battery will run the amplifier at full power for 30mins.
Go for the biggest capacity you can, but make sure you're still okay to carry it around - no point in making something that'll play all day and all night if you can't actually lift it. Compromises, compromises.
Follow the video through and you'll be good to go.
Good luck!
Chris
Oops, I couldn't find any 24V SLA batteries on Buy online and sell with NZ's #1 auction & classifieds site | Trade Me
I could, however, find 12V SLA batteries. Chris could you do me a favour and have a look on that trademe site to see which battery is suitable please? Will this one (7.2 Amp Hour 12V SLA Battery (Ideal for Alarms etc | Trade Me) do?
Cheers!
Jo
I could, however, find 12V SLA batteries. Chris could you do me a favour and have a look on that trademe site to see which battery is suitable please? Will this one (7.2 Amp Hour 12V SLA Battery (Ideal for Alarms etc | Trade Me) do?
Cheers!
Jo
Hi Jo-ann,
You'd need two of the 12v batteries to make up the right voltage. When you connect them in series (ie, in a chain), their voltages add up. I can't seem to find any 24v batteries on that particular site.
The reason I'd recommend 24v use is that the amplifier will just about work at 12v, but if the voltage goes lower (ie, the battery starts to lose charge), the amplifier won't have enough volts to work. With a 24v system, you can lose a fair few before the amplifier shuts down.
Hope this helps,
Chris
You'd need two of the 12v batteries to make up the right voltage. When you connect them in series (ie, in a chain), their voltages add up. I can't seem to find any 24v batteries on that particular site.
The reason I'd recommend 24v use is that the amplifier will just about work at 12v, but if the voltage goes lower (ie, the battery starts to lose charge), the amplifier won't have enough volts to work. With a 24v system, you can lose a fair few before the amplifier shuts down.
Hope this helps,
Chris
Oh I see, well looks like I'd have to source for some 24V batteries then because it's not practical for me to use two 12V batteries in this setup. Are there amps that work on 12V batteries or will it not work with the speakers that I'm using? I'm sure on my friend's boombox he only uses one 12V battery. I could be wrong though...
Sorry for the load of questions, I just want to make sure I'm getting the right things because I can't find any place that sells amplifier boards in New Zealand and I'll have to buy them online = lots of hassle for me. Cheers ^.^
Sorry for the load of questions, I just want to make sure I'm getting the right things because I can't find any place that sells amplifier boards in New Zealand and I'll have to buy them online = lots of hassle for me. Cheers ^.^
For battery powered equipment, efficiency is generally the over-riding factor.
That requires high efficiency speaker and high efficiency amplifier and high efficiency PSU.
Even monitoring LEDs will reduce the life from a single charge.
That requires high efficiency speaker and high efficiency amplifier and high efficiency PSU.
Even monitoring LEDs will reduce the life from a single charge.
You could get yourself a 12v battery and use an amplifier intended for car use.
However, it's difficult to cut through all the crap on eBay to find the one or two actually worth having. A lot of the stuff will never give out the power that's claimed and survive. The board I linked has been used on this forum before, so it's known to work and give a decent power output.
(having read it again)
The board I linked to will work down to 10v, so you have some lee-way before it shuts down because the battery is flat. You won't get the full power output from the reduced supply voltage, but I'd expect the sound to be much better than some of the cheap car amplifiers available.
So, a single 12v battery will work okay, but doubling them up (as a potential upgrade) will give you more volume.
Chris
However, it's difficult to cut through all the crap on eBay to find the one or two actually worth having. A lot of the stuff will never give out the power that's claimed and survive. The board I linked has been used on this forum before, so it's known to work and give a decent power output.
(having read it again)
The board I linked to will work down to 10v, so you have some lee-way before it shuts down because the battery is flat. You won't get the full power output from the reduced supply voltage, but I'd expect the sound to be much better than some of the cheap car amplifiers available.
So, a single 12v battery will work okay, but doubling them up (as a potential upgrade) will give you more volume.
Chris
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