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Brad
24th August 2009, 02:05 PM
Okay, I've been thinking of my next jukebox build and I have some good ideas but one thing thats been an issue is sound output.

I currently use an Altec Lansing Sub with Car Audio speakers and it works really well BUT it's maximum volume is not what it should be. This is more the fault of using pc spec'd sub/amp.

Anyway the other option is to use home audio equipment but most is too damn big for what I want so I did some hunting and cam across this as an example of what I'm looking for:

http://cgi.ebay.com.au/Tripath-Class-T-Amp-Mini-Amplifier-20WX2-Power-supply_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2em14Q QhashZitem1c0beecf70QQitemZ120459284336QQptZAUQ5fE lectronicsQ5fAudioQ5fAmplifiersQQsalenotsupported

My question is, what are the downsides of something like this? Would it do what I was after? What sort of RMS/PMPO should I be looking for? I have no bloody idea :confused:

Brad

AskJacob
24th August 2009, 02:10 PM
Okay, I've been thinking of my next jukebox build and I have some good ideas but one thing thats been an issue is sound output.

I currently use an Altec Lansing Sub with Car Audio speakers and it works really well BUT it's maximum volume is not what it should be. This is more the fault of using pc spec'd sub/amp.

Anyway the other option is to use home audio equipment but most is too damn big for what I want so I did some hunting and cam across this as an example of what I'm looking for:

http://cgi.ebay.com.au/Tripath-Class-T-Amp-Mini-Amplifier-20WX2-Power-supply_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2em14Q QhashZitem1c0beecf70QQitemZ120459284336QQptZAUQ5fE lectronicsQ5fAudioQ5fAmplifiersQQsalenotsupported

My question is, what are the downsides of something like this? Would it do what I was after? What sort of RMS/PMPO should I be looking for? I have no bloody idea :confused:

Brad

I once heard "P.M.P.O." referred to as "Peak Marketing Power Output" as it is a load of codswollop.

Here is the thing: the unit is powered by a 12v 2Amp supply. Therefore if it were 100% efficient (which it won't be) the MAX power this thing can "send" to the speakers is 24 Watts (or 12 Watts per channel).

I think you may be underwhelmed by this amp too - it cannot deliver what it promises... (although it may deliver this bit "It has flash rainbow light in the front panel and very colorful at night" :) )

cheers
Jacob

Brad
24th August 2009, 02:13 PM
I think you may be underwhelmed by this amp too - it cannot deliver what it promises... (although it may deliver this bit "It has flash rainbow light in the front panel and very colorful at night" :) )

cheers
Jacob

LOL thanks for that yes I'm not after the light thats for sure and wasn't necessarily looking at this particular item, just for something similiar that wasn't going to cost me hundreds.

Cheers,
Brad

AskJacob
24th August 2009, 02:17 PM
Honestly, it depends more on how efficient your speakers are. 10W per channel could be all you need.

If you are using car speakers you need to keep in mind they are 4ohm, make sure any amp module you look at can handle that load. The volume problem you have may be that the altec lansing gear is expecting an 8ohm speaker...

There are hundreds of car audio amps out there, and a lot are cheap enough to try. I'd skip that unit you were looking at as it seems more aimed to the "mp3 player booster" crowd.

Cheers
Jacob

Davefjedi
24th August 2009, 02:25 PM
(although it may deliver this bit "It has flash rainbow light in the front panel and very colorful at night" :) )

cheers
Jacob

:lol:lol:lol

Brad
24th August 2009, 02:27 PM
So again maybe not this particular model but something along these lines?

http://cgi.ebay.com.au/500W-Stereo-Power-AMP-RCA-Amplifier-Car-Boat-Motorcycle_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2e m14QQhashZitem1e580be27fQQitemZ130326192767QQptZAU Q5fCarQ5fPartsQ5fAccessoriesQQsalenotsupported

Cheers,
Brad

gints
24th August 2009, 02:57 PM
One thing I learnt when I built the sound system for my first car about 6 years ago was not to skimp on amps. I used some shitty Sony XPlode and some Autobahn brand, they all sounded like shit, didn't last long, just shit. Went and bought some decent amps for my subs and splits and they fired without a hitch for 5 years till I sold it all.

What would the USB Out jack do on that second one...

AskJacob
24th August 2009, 03:10 PM
What would the USB Out jack do on that second one...

give about 5v 1/2A for charging your ipod/mp3 player.

Cheers
jacob

Brad
24th August 2009, 03:10 PM
What would the USB Out jack do on that second one...

Marketed as a USB charger for iPods etc, especially as these units are designed to boost the output of portable media players

Brad

dmworking247
24th August 2009, 03:26 PM
Brad I hope you don't mind if I weigh in on this discussion with similar questions.

I've been contemplating building a dedicated jukebox too, with a touch screen 15" PC on a top unit, that sits on top of an 'audio unit' underneath, which contains a suitable amp, a single 10" or 12" subwoofer, and two speakers. The idea being that you can take the jukebox (PC) on its own and plug it into a bigger stereo, or use it as an all-in-1.

Similar to you, my trouble has been with selecting the amplification/audio gear. I'm inclined to go with car audio speakers & sub because they're more affordable at a component level (ie without all the enclosures/etc from home audio)... however I've always gotten stuck with the 12v power supply side.

AJ/others, I figured on getting a 4 chan car amp, bridging two of the channels for the sub (with the right frequency control on the amp I expect), and running the other two to the speakers? More importantly, what are the implications of using a 240v > 12v transformer? Would an arcade PSU do the job, or not enough amps? What are the alternatives?

Brad
24th August 2009, 03:36 PM
Go for it Dale. the more input the better. Funny you should mention your plans. I'd originally planned to do a 2 piece version.

Top half detaches and is self contained with either PC Style 2:1 AND Home audio Output ports.

When combined with bottom half outputs to bottom set of Amp and satelites with home audio equipment.

Then I thought about it and realised that if I was going to make a 2 piece unit, I'd be able to transport it easily anyway so no point in this design. I could however change my mind.

The option I'm looking at now it a single unit with 2 monitors.

I have a 19" touchscreen which would be at the top and be used for the main display.

My other touchscreen is a 15" model and I would use this for software display. Basically track/video selection.

The lower 15" touchscreen is framed and I would have it hinged so it could swing up/down for storage, movement etc but when in use be angled and high enough for easy viewing and use.

The base of this unit would house a sub and 2 speakers.

I'd then finish the unit off with LED lighting driven by the LED Wiz I have.

Brad

spacies
24th August 2009, 04:53 PM
Brad I hope you don't mind if I weigh in on this discussion with similar questions.

I've been contemplating building a dedicated jukebox too, with a touch screen 15" PC on a top unit, that sits on top of an 'audio unit' underneath, which contains a suitable amp, a single 10" or 12" subwoofer, and two speakers. The idea being that you can take the jukebox (PC) on its own and plug it into a bigger stereo, or use it as an all-in-1.

Similar to you, my trouble has been with selecting the amplification/audio gear. I'm inclined to go with car audio speakers & sub because they're more affordable at a component level (ie without all the enclosures/etc from home audio)... however I've always gotten stuck with the 12v power supply side.

AJ/others, I figured on getting a 4 chan car amp, bridging two of the channels for the sub (with the right frequency control on the amp I expect), and running the other two to the speakers? More importantly, what are the implications of using a 240v > 12v transformer? Would an arcade PSU do the job, or not enough amps? What are the alternatives?

Hmmmm, I bought an old pair of Energy 4.1e speakers (Home Audio) for $45. These were around $900 a pair back in the early 90's/ and I am pretty sure these will smoke over cheap car audio. They will be going in to my own jukebox and will just stay in their existing cabinet in a space in the bottom of the juke but behind some grill cloth.

The money you spend on inverter to get a car amp to run on mains power isn't worth it. Just use a home amp.

No an arcade PSU won't have anywhere near enough grunt to power a car amp.

I have said it many times on here but no-one seems to care but I will keep saying it: USE HOME AUDIO GEAR!!!!! Its just a lot easier.

Brad
24th August 2009, 04:55 PM
I have said it many times on here but no-one seems to care but I will keep saying it: USE HOME AUDIO GEAR!!!!! Its just a lot easier.

It's not that we don't believe you, it's just difficult/impossible to find home audio gear that is a) the small b) affordable

=(

Brad

spacies
24th August 2009, 04:58 PM
Brad, what do you mean by small?
How big we talking here? Driver size?

Brad
24th August 2009, 05:01 PM
LOL sorry, more like area of unit.

My current one is a lowboy which I want to restore to a proper arcade cab. My future one whilst taller is much leaner in depth so not a lot of room for home audio gear if at all.

Brad

David_AVD
24th August 2009, 05:02 PM
Bang & Olufsen make some amazing Class-D amplifier modules (http://www.icepower.bang-olufsen.com/). There are 250W modules that need no heatsink and have an on-board switchmode power supply. I've used these and they do kick ass!

acejas
24th August 2009, 05:02 PM
i hear ya spacies

what kind of price david?

spacies
24th August 2009, 05:06 PM
LOL sorry, more like area of unit.

My current one is a lowboy which I want to restore to a proper arcade cab. My future one whilst taller is much leaner in depth so not a lot of room for home audio gear if at all.

Brad

Plenty of room mate.
What sort of price we talking for the speakers and amp?

dmworking247
24th August 2009, 05:08 PM
I have said it many times on here but no-one seems to care but I will keep saying it: USE HOME AUDIO GEAR!!!!! Its just a lot easier.

When have you ever said that man? You're making this up. I suppose you've told us to use automotive lacquer paints on our cabs instead of enamel spray cans too eh? :laugh:

spacies
24th August 2009, 05:35 PM
When have you ever said that man? You're making this up. I suppose you've told us to use automotive lacquer paints on our cabs instead of enamel spray cans too eh? :laugh:

You be quiet.

What about THIS (http://cgi.ebay.com.au/Technics-stereo-components-speakers_W0QQitemZ250485053541QQcmdZViewItemQQptZA U_hifi_system?hash=item3a52129865&_trksid=p3286.c0.m14)


OR THIS (http://cgi.ebay.com.au/PIONEER-HOME-STEREO-UNIT_W0QQitemZ280387106257QQcmdZViewItemQQptZAU_hi fi_system?hash=item41485fb5d1&_trksid=p3286.c0.m14) (sell of components not used.

Crafty
24th August 2009, 08:41 PM
I have to agree with Spacies. troll evil pay and a decent Amp and speakers will pop up.

Car Audio whilst small in size ends up in my opinion small in sound..

dmworking247
24th August 2009, 09:44 PM
In my case, I'm hoping to make the audio enclosure (seperate from the PC/touchscreen enclosure) in something the size of a large speaker, or a dual car subwoofer box.

If I went for home audio gear, are you suggesting I'd de-case an old technics amp and put it inside the box? What about considerations of heat, and magnetism from a subwoofer etc?

The advantage of a car amp (as I saw it) was pure amp, set volume... everything else was done at the 'head deck' (or in this case, the pc). Using a home amp leaves a lot of controls on the amp itself.

Claude
24th August 2009, 10:29 PM
I have just what you guys are looking for;

http://www.earthquakesound.com/cng_7.htm

That is a US$ price but I'm sure I can work out an AA special price for those interested. ;)

I have one sitting in my lounge right next to my NOS cocktail :laugh:

Some specs;

- 300w RMS (real watts) per channel @ 8-Ohm x or 600w @ 4-Ohms (x7 channels)
- requires a (pretty much dedicated) 20A 240V power circuit (20A breaker on back of amp)
- 55kgs

I've run 2 channels at almost full power and measured around 4A of current with a clamp metre at my switch board. So running 7 channels should suck around 15-20A. Rediculous!

I've had to custom build a dolly for it just so I can move it to the lounge for when I need to demo it.

Now seriously, listen to what Spacies has to say and get yourself a decent cheap home audio amp off ebay or at a thrift store with some decent speakers. There's some great bargains to be had for 'old' stereo amps that would be ideal for your juke.

To expect to get half decent sound from a new ~$20 amp off ebay is stretching it a bit.

spacies
25th August 2009, 04:35 AM
In my case, I'm hoping to make the audio enclosure (seperate from the PC/touchscreen enclosure) in something the size of a large speaker, or a dual car subwoofer box.

If I went for home audio gear, are you suggesting I'd de-case an old technics amp and put it inside the box? What about considerations of heat, and magnetism from a subwoofer etc?

The advantage of a car amp (as I saw it) was pure amp, set volume... everything else was done at the 'head deck' (or in this case, the pc). Using a home amp leaves a lot of controls on the amp itself.

Perfect! Remove the drivers from the cabs and put them in your new speaker 'area'. Make sure you use all the internal lining from the old cabs and add more if you want. You could get fancy and mount the tweeters at ear level which is what I plan to do. You also have the crossover sorted as well which will eliminate the 'shoutiness' from something that doesn't.

You would only have to remove the top part of the amp case and weren't you going to add a fan anyway :p A car amp would need the same thing. If you want to spend $50+ on an inverter and use a car amp then go for it but that $50 would probably buy you a good amp and you are set. I don't know about you but I would prefer an actual dial to adjust the volume rather than doing it on screen. So removal and mounting of the volume pot to the cab may be a good idea.


I have just what you guys are looking for;

http://www.earthquakesound.com/cng_7.htm

That is a US$ price but I'm sure I can work out an AA special price for those interested. ;)

I have one sitting in my lounge right next to my NOS cocktail :laugh:

Some specs;

- 300w RMS (real watts) per channel @ 8-Ohm x or 600w @ 4-Ohms (x7 channels)
- requires a (pretty much dedicated) 20A 240V power circuit (20A breaker on back of amp)
- 55kgs

I've run 2 channels at almost full power and measured around 4A of current with a clamp metre at my switch board. So running 7 channels should suck around 15-20A. Rediculous!

I've had to custom build a dolly for it just so I can move it to the lounge for when I need to demo it.

Now seriously, listen to what Spacies has to say and get yourself a decent cheap home audio amp off ebay or at a thrift store with some decent speakers. There's some great bargains to be had for 'old' stereo amps that would be ideal for your juke.

To expect to get half decent sound from a new ~$20 amp off ebay is stretching it a bit.

That thing is a beast! Awesome.

Glad you jumped in mate. Claude knows home audio :D
I honestly don't know why people insist on car audio when the real bargains are in a proven system.

I would like to remind you all that the primary function of a juke is to play music and play it well. Nobody would want to listen to it if it sounds like shit no matter how good looking it is.

WOKA
25th August 2009, 11:45 AM
I was really happy with my two hour jobbie in the Kiosk.. Used a spare Sony HT amp and floor standing speakers.. Sounds great. Just need to integrate the speakers into the kiosk and its all go..