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After class I'll find the right ones for you, I forgot I got them elsewhere because PE was overpriced for those buttkicker branded ones.
So I got myself an amplifier today from a flea market. I want to replace my current broken hifi system with this, but the problem is it has no aux on it and I want to connect it to my PC. It looks like this (from the back): [IMG]http://i.imgur.com/EhFNf6M.jpg[/IMG] I can't even find a manual for it, only the service manual which only has electronic circuits in it and I don't know that much about electronics. Thought maybe I could hook it up from phono with RCA to 3.5mm jack but I'm not sure if that's a good idea.
[QUOTE=Martti010;39506447]So I got myself an amplifier today from a flea market. I want to replace my current broken hifi system with this, but the problem is it has no aux on it and I want to connect it to my PC. It looks like this (from the back): [IMG]http://i.imgur.com/EhFNf6M.jpg[/IMG] I can't even find a manual for it, only the service manual which only has electronic circuits in it and I don't know that much about electronics. Thought maybe I could hook it up from phono with RCA to 3.5mm jack but I'm not sure if that's a good idea.[/QUOTE] Any of the line ins will work.
[QUOTE=Shadaez;39506453]Any of the line ins will work.[/QUOTE] Oh I thought I would need to fill that RC-BUS for Tape to work, so I could hook RCA cables to Tape Line In and 3.5mm jack to line out?
Yeah. Just don't plug it into the phono jack :v:
Thanks guys. But darn, I noticed a problem, my speakers' impendance are 6 ohms each and the amplifier allows for 8 ohms, and I just read on the net that it can damage the amp. I did try them before I saw that, it worked but there was this really nasty crumbling going on. Bet this was because of different impendances. Is there something that I could do about it? I need new speakers anyway though, current ones are a bit broken.
There's not really anything you can do. I actually run my system with a 4 ohm sub and 6 ohm bookshelf speakers on a 8-16 ohm amp :v I think it's fine as I don't let it play so loud the security relays cut it off, though. I hope, heh.
hmm the crumbling sound was really weird though, could it also be caused because of the speaker wires not inserted into amp correctly? They were as in as I could get them. It first didn't want to play (probably badly hooked speakers), then suddenly both speakers started playing. It played fine until the sub bass part came in, then the crumbling started throughout the song. The amp could be damaged though, I still bought it in a flea market (for 30€) although they said that it's working fine and it was tested there.
Could be a bad connection, yeah. Could you maybe make a recording of the sound it makes?
[QUOTE=Warship;39509249]Could you maybe make a recording of the sound it makes?[/QUOTE] Sure, I'll probably do it tomorrow, it's pretty late here.
Anybody who wants a tiny amp should check [URL="http://www.amazon.com/gp/product/B003P534SW/ref=s9_simh_gw_p23_d2_i1?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-4&pf_rd_r=061NHQ370SZYZVGRCQ1H&pf_rd_t=101&pf_rd_p=470939031&pf_rd_i=507846"]this[/URL] out.
[QUOTE=loophole;39509411]Anybody who wants a tiny amp should check [URL="http://www.amazon.com/gp/product/B003P534SW/ref=s9_simh_gw_p23_d2_i1?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-4&pf_rd_r=061NHQ370SZYZVGRCQ1H&pf_rd_t=101&pf_rd_p=470939031&pf_rd_i=507846"]this[/URL] out.[/QUOTE] [video=youtube;1nNK8Nc73i4]http://www.youtube.com/watch?v=1nNK8Nc73i4[/video]
what are those 2 nobs next to the volume?
Bass and Treble. Lepai amps are REALLY poorly made. You get what you pay for. [img]http://i760.photobucket.com/albums/xx249/nettofoto/2009-07-21-lepai-ta2020-amplifier-0.jpg[/img]
[QUOTE=MIPS;39511577]Bass and Treble. Lepai amps are REALLY poorly made. They burn out if used long term with anything big. [img]http://i760.photobucket.com/albums/xx249/nettofoto/2009-07-21-lepai-ta2020-amplifier-0.jpg[/img][/QUOTE] Honestly what do you expect for $20? It was the best reviewed and cheapest small amp I could find on Amazon.
[QUOTE=loophole;39511608]Honestly what do you expect for $20? [/QUOTE] Point taken. :v:
Here's the video (more like audio) of the noise distortion (skip to around 0:56): [video=youtube;WcU0lJwWwv0]http://www.youtube.com/watch?v=WcU0lJwWwv0[/video] Notice how it sounds clean before the sub bass kicks in and right speaker starts stuttering on/off. Can it be a broken amplifier? [B]Edit: [/B] It must be the amp.. While the right speaker wasn't working, I turned up the bass knob, right speaker started working, I turned it to default again, right speaker faded away with crumbling. Guess that's wasted 30 euros.. :/ Is there any (European) alternatives to the mini-amp discussed above? It seems pretty sweet but it isn't sold here in Finland :/ [B]Edit again: [/B] I think I figured out I might have too weak speaker-to-amp wires, the right speaker is especially badly working and probably because it has a really thin wire. I could take a pic tomorrow if wanted.
it's not your wires, it sounds like it's clipping or something [editline]9th February 2013[/editline] and by your description something sounds very wrong with your amp
I think you've fried the voice coil in the speaker. If you lightly push the cone (Use all your fingers to press down evenly round the thing, don't push one side), does it move freely or does it make a scraping noise?
[QUOTE=Tezzanator92;39526621]If you lightly push the cone (Use all your fingers to press down evenly round the thing, don't push one side), does it move freely or does it make a scraping noise?[/QUOTE] it doesn't make any sound, it moves fine, both of them. My dad told me that it's over-amplifying the speakers (since the speakers' impendance are 6ohms and amp's impendance is 8ohms) so it might as well be clipping. I hope to buy new speakers in near future (with 8 ohms or maybe slightly higher) so I will test if it works without that nasty noise. Hmm, I could do a clipping test on different frequencies, like starting with low volume and cranking it up a bit.
I wouldn't push the amp too much if you are driving 6 ohm speakers. Could damage the amp.
[QUOTE='[EG] Pepper;39528836']I wouldn't push the amp too much if you are driving 6 ohm speakers. Could damage the amp.[/QUOTE] I'm aware of it, I played it at very low volume.
Any in-depth information on power ratings? I've come to understand many receivers perform vastly under their power ratings, true? I was wondering how some modern and relatively cheap 5.1 receiver with 100WPC at 8ohms would compare to an integrated amplifier that has 50WPC at 8 ohms. receiver in question is this, [url]http://www.amazon.com/Yamaha-R-S300BL-Stereo-Theater-Receiver/dp/B0044779H2[/url]
Question here: I've got Turtle Beach X12 and when I plug it into the USB port, static noise from other USB devices comes out- the mouse hums, the keyboard hisses, external HDD makes a revving noise. Is there a way to cancel this noise out?
[QUOTE=Lamar;39533957]Any in-depth information on power ratings? I've come to understand many receivers perform vastly under their power ratings, true? I was wondering how some modern and relatively cheap 5.1 receiver with 100WPC at 8ohms would compare to an integrated amplifier that has 50WPC at 8 ohms. receiver in question is this, [url]http://www.amazon.com/Yamaha-R-S300BL-Stereo-Theater-Receiver/dp/B0044779H2[/url][/QUOTE] they will all perform under their ratings as long as the volume isn't maxed out. when you see "50wpc" or "100wpc" it means that it is capable of handling up to that much, but it isn't a good idea to max the volume especially when using a digital source, as it can easily clip. A 100wpc amp turned up to 50% will sound basically as loud as a 50wpc amp turned all the way up (assuming of course that the 50w amp isn't clipping)
[QUOTE=Lamar;39533957]Any in-depth information on power ratings? I've come to understand many receivers perform vastly under their power ratings, true? I was wondering how some modern and relatively cheap 5.1 receiver with 100WPC at 8ohms would compare to an integrated amplifier that has 50WPC at 8 ohms. receiver in question is this, [url]http://www.amazon.com/Yamaha-R-S300BL-Stereo-Theater-Receiver/dp/B0044779H2[/url][/QUOTE] I love the power ratings on that product. "Dynamic power per channel". I'm a Yamaha fan but that's just bollocks. From reading the manual at anyone time 100W of power can be delivered to all channels with up to a maximum of 50W on a channel. This will be down to the power supply they are using, hence why the power rating is spread over the channels. [b]Power ratings[/b] Power ratings are a tricky beast because there's no rating really that will tell you what anything that pertains to [u]your[/u] listening habits, there are a couple of things to look out for. The power ratings you want to be looking at are RMS and Music power. Peak power is not useful and neither are manufacturer specific terminologies such as "Dynamic power", They don't tell you anything and you don't know what their testing methodology is or under what circumstances those numbers were reached. Seen those tiny desktop PC speakers with "1000W P.M.P.O (Peak Music Power output)", Laughable. RMS will give you a power rating that you can use to compare amplifiers, it is also recognised as the standard for measuring power output. This measurement is not without its flaws due to varying testing methodology but it's the best you're going to get on consumer gear (until they start using AES standards such as band-limited pink noise)! Music power is a strange one because there are no "rules" for measuring it, it does have SOME use though when it comes to speakers, not amplifiers. When you run a speaker as high volumes the voice coil inside will heat up, but if you are playing something with a high crest factor, such as most music, then there are periods when the power given to the speakers is well below it's thermal limits. Crest factor is the difference in dB between the average and peak levels in your content.Your average compressed rock song has a crest factor of around 6dB. This will allow you to push your speakers a bit further than the "RMS" specification for certain content. This is the reason in my live sound systems my amplifier's RMS ratings are about 80% more than the RMS ratings of the speakers (Or roughly equal to the speakers "music" or "programme" rating). Because I know that given the crest factor of live content I have a lot of headroom to spare. Running amps to their limits sounds awful. If you know what you are doing you will never break a speaker with an oversized amplifier. I've not tested it myself but many believe the clipping from an underpowered amplifier is worse than the clean power from an oversized amplifier, it certainly sounds worse either way. [b]Impedance - Ω[/b] Impedance (in Ohms Ω) is the measure of the load presented to your amplifier by a certain speaker. Because speakers and audio equipment use an alternating current we call it Impedance, NOT resistance. Generally You'll find speakers with an impedance of 16Ω, 8Ω, 6Ω, 4Ω or 2Ω. But why does it matter? It matters because amplifier's power ratings are given at a specific load, for example, let's use these specifications of a fictional amplifier: [code] Power output: 2 x 200W RMS @ 4Ω 2 x 225W EIA 1Khz/1%THD @ 4Ω 2 x 420W Music power @ 4Ω [/code] So this amplifier gives you a fairly comprehensive range of power outputs, but only into a 4Ω load! For a solid state amplifier you tend to get around double the wattage for half the impedance, this is ONLY a rule of thumb and doesn't apply in all cases, the newer Class D amplifiers are making this a bit more complicated. Generally, if they don't publish full specs at varying impedances, I don't want to know. When you put speakers in parallel, the power the amplifier gives out it split between the speakers, two 8Ω Speakers (4Ω) on an amplifier giving out 400 watts will see 200 watts each. This distribution is proportional to each speaker's impedance, it's split equally here because both speakers have the same impedance. [u]Combining speakers[/u] When you put two speakers on a single amplifier channel, you have two choices on how to wire it, Series and parallel: [img]https://dl.dropbox.com/u/286964/fpdrop/user42347_pic133877_1249369080.gif[/img] When you put two speakers in series you add the impedance together, two 8Ω speakers will present a 16Ω load to the amplifier. Usually though, you'll be wiring them in parallel, and the math is a little more complicated. There is a shortcut though, if the two speakers are of the same impedance then you just divide by 2. Two 8Ω speakers in parallel would present a 4Ω load to the amplifier. [u]Minimum Impedance[/u] All amplifiers have a minimum impedance they can handle, the most common for consumer gear is 4Ω minimum. This means you could put: [code] 2 x 8Ω Speakers in parallel = 4Ω 4 x 16Ω Speakers in parallel = 4Ω 1 x 6Ω Speaker = 6Ω [/code] And so on. If you go below this minimum then depending on the amplifier a couple of things could happen: It could run fine but get hot and cut off. It may have a cut out if it senses a short across the terminals, this may trip. It may run fine then suddenly give out DC to your speakers causing your speakers to glow red hot and burst into flames (Some old Chinese cloned Lab Gruppen amplifiers were notorious for this!) [b]Do watts matter?[/b] Well, Not really. There's other measurements to take into account if you have them, such as Total harmonic distortion (%THD) which generally goes up as you reach an amplifiers limits. Then there's the sensitivity of your speakers, You could be pushing 1000W watts but if your speakers are hilariously inefficient then they could be putting out less actual sound than 300W into high efficiency speakers. And on top of that, it takes ten times the power to double the apparent volume. [code] 1W -> 10W = Double Volume 10W -> 100W = Double Volume 100W -> 150W = About 1.8db change for an average sensitivity (85db 1W/1M) speaker. [/code] Where watts matter is choosing an amplifier with suitable headroom and getting a clean sound, get big amps and don't push them too hard and they'll reward you with clean amplification! My rule of thumb is, if the manufacturer can't provide concrete comprehensive specifications and uses silly things like "Dynamic power", I won't buy. Note: I have not proof read this post yet, I will later on.
this is a bit of a stretch.. but can anybody recommend me a pair of decent sounding studio speakers for under $250? I'd need an amp and/or receiver as well correct? Sorry i'm pretty clueless when it comes to audio
[QUOTE=Akito8;39543459]this is a bit of a stretch.. but can anybody recommend me a pair of decent sounding studio speakers for under $250? I'd need an amp and/or receiver as well correct? Sorry i'm pretty clueless when it comes to audio[/QUOTE] some have built in amps, so you don't necessarily need a receiver. [b]below are self-powered speakers that have their own amp and power cord[/b] [thumb]http://ecx.images-amazon.com/images/I/81wvgS1jrBL._AA1500_.jpg[/thumb] Although most speakers are passive and require an external power source such as an amp or receiver, and only have the below for inputs [img]http://ecx.images-amazon.com/images/I/31OQ0%2BdM6eL._SL500_AA300_.jpg[/img] [editline]10th February 2013[/editline] As for recommendations, with your budget you can get some very good self-powered speakers such as the [url=http://www.amazon.com/Avid-9900-65174-09-M-Audio-BX5-D2/dp/B005F3H6Q8/ref=sr_1_7?s=musical-instruments&ie=UTF8&qid=1360539832&sr=1-7&keywords=speakers]M-Audio BX5 D2[/url] if you're hooking up the BX5D2 to your computer, make sure to get [url=http://www.amazon.com/Hosa-Cable-CMS105-inch-Adapter/dp/B000068O35/ref=pd_sim_MI_8] a proper adapter[/url]
[QUOTE=Barbarian887;39543657]some have built in amps, so you don't necessarily need a receiver. [b]below are self-powered speakers that have their own amp and power cord[/b] [thumb]http://ecx.images-amazon.com/images/I/81wvgS1jrBL._AA1500_.jpg[/thumb] Although most speakers are passive and require an external power source such as an amp or receiver, and only have the below for inputs [img]http://ecx.images-amazon.com/images/I/31OQ0%2BdM6eL._SL500_AA300_.jpg[/img] [editline]10th February 2013[/editline] As for recommendations, with your budget you can get some very good self-powered speakers such as the [url=http://www.amazon.com/Avid-9900-65174-09-M-Audio-BX5-D2/dp/B005F3H6Q8/ref=sr_1_7?s=musical-instruments&ie=UTF8&qid=1360539832&sr=1-7&keywords=speakers]M-Audio BX5 D2[/url] if you're hooking up the BX5D2 to your computer, make sure to get [url=http://www.amazon.com/HOSA-CMP-110-Mono-Interconnect-3-5mm/dp/B000068O3D/ref=sr_1_10?s=musical-instruments&ie=UTF8&qid=1360540201&sr=1-10&keywords=3.5mm+to+1%2F4+adapter]a proper adapter[/url][/QUOTE] erm you mean [url]http://www.amazon.com/Hosa-CMP159-Stereo-Breakout-10-Feet/dp/B005HGM1D6/ref=pd_bxgy_MI_img_z[/url]
[QUOTE=Shadaez;39544296]erm you mean [url]http://www.amazon.com/Hosa-CMP159-Stereo-Breakout-10-Feet/dp/B005HGM1D6/ref=pd_bxgy_MI_img_z[/url][/QUOTE] no... [thumb]http://ecx.images-amazon.com/images/I/81Qam8wF1FL._AA1500_.jpg[/thumb]
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