Amps

Say, I thought I'd ask seeing as I got a little extra money to burn from christmas, anyone got any old/unused car amps they might want to sell to moi? My current sub amp is ever increasingly scaring me and my sub sound's like it's blown a voice coil or something (although I know if it were blown it wouldn't be working as good as it is). What do you got to say Nachomama?

Topic by Punkguyta   |  last reply


Amp to sub amp?

I wanna amp a sub but the only amp I have is a standerd amp how can I make this so audio out of the amp is really bassy part of the music  and with the plugs there 3 wire yellow white and just in there  mid the loos one ground yellow right and white left

Question by R.A.T.M   |  last reply


Electromagnet Amp

I need to build an amp circuit for an electromagnetic signal, but I don't know much about amp cicuitry. I am goin to amplify a 7800 Hz siganl from an mp3 player through a coil. I'm making one of those cart locker things. Any ideas?

Topic by gimmelotsarobots   |  last reply


Suggestions for amp? Answered

Hello all, As my question shows, I am looking for suggestions of amps I should use to drIve my speakers. There are 2 speakers RMS rated at 3.7W and 4ohm. Any suggestion is appreciated. Many thanks in advance EDIT: it would be best for the amp to use less than 9v so that it is still portable.  Please suggest 

Question by michalk1   |  last reply


problem with amp....? Answered

There is power but no sound output,there are relays in side that click on iv have a prob and there is power to about half the board just not out put stage and i know that there is a speaker protection that is probable not letting power through for some unknown reason\r\nsansui au-x410r rated at 180 w   240v does any1 have a surgestions on problem or how to get hold of a service manuel

Question by andybuda   |  last reply


how do i lower the milliamps in my adjustable adaptor?

Hi it seems i need to lower the milliamps, currently at 1500, in my adjustable adaptor in order to run a small dc motor that usually runs with a rechargeable 2.6v battery. i think the ohm rating was 006.5 but im not sure. im trying to test these motors without having to bother to charge up loads of batteries all the bloody time. but i cant test them accurately as the motors run alot faster when plugged into the mains using the adaptor. what do you think is the best solution?

Question by jbasham1   |  last reply



Ruby amp 9v DIY guitar amp

The Ruby amp (by Runoffgroove.com) is quite simply the best 9v guitar amp on the planet. Ruby has many shades of sparkly clean all the way up to a great, natural overdrive. Because of its small size and low power consumption its perfect for building your own cigar box amp or mounting into a guitar pedal enclosure. If you have never done a diy electronics project then this is a great way to get started.  The kit comes all the parts you need  - pcb, resistors, caps, jacks, led, 9v battery snap and instruction sheet. Also I have added a couple of parts that you never seem to get included in commercial kits - a toggle switch and a dc jack (so you can run off a wallwart). Its fun, educational and at the end of the buid you have a real great sounding amp that can be used for busking, practicing in the park or for homerecording with a microphone. There are plenty of small output LM386 kits out there - only the Ruby is a real guitar amp as it has a jfet input buffer and a real gain control - oh and thers mods that can be done :) check it out at www.rubyamp.com - heaps of videos and sound samples cheers

Topic by dogbox2012   |  last reply


How to increase amps?

I heard ampere could be increased by capacitor. If true then how to do it???

Question by simba1   |  last reply


Do Amps matter?!?

Ok, I need a charger for my motorolla two way radios. I have the dock, only need a DC power supply. on one of them it states "18Volts DC +/- 20%, 15.3 watts" .Lets say I get 18VDC 1amp power supply, that's 18W,it means it's an overkill? or 15V 2Amps? As I understand, usually amps don't matter, as the item draws as much as it needs, but since it is a charger.. Cheers for the teh help!

Question by zhgutas   |  last reply


Power Amp Build?

I was wondering if there is anyway to turn a set of old computer speakers (the amp inside the computer speakers more particularly) into a power amp? I know it would be a pretty pathetic power amp but I was wondering how I could do it.

Topic by batboy61490   |  last reply


Which is the better amp? Answered

Hey Guys, I have attached two schematics of two different amps. Can you tell me which is better like  better quality, louder etc,

Question by SA-DIY   |  last reply


10W audio amp?

Ok, so i want to get this one audio amp to work, but i can't seem to figure out how to wire it! the first picture is a schematic, and i have NO idea what the connections are, 1, 2, and 3 the second is a picture of the amplifier chip

Topic by Sandisk1duo   |  last reply



Tube headphone amp

I want to build a tube headphone amp. Is it possible to make a smps (switch mode power suply) to power it? It would be like a mix between old and new technology!

Topic by dwj300   |  last reply


sony xplode amp

I have an car audio amp that i need the schematics for, the model is: XM-SD22X. was wondering if anyone can help. have been able to find owners manual and such. but not much help.

Topic by waybrane 


millamps vs amps? Answered

I have a mp3 player which uses a 1.5 volt/15 amp AA battery. I would like to use rechargeable battery, but find most are 1.2 volt and 2000 millamps. Would this damage my mp3 p

Question by waynf   |  last reply


Specialized lm386 amp? Answered

I want to make a amplifier like this https://www.instructables.com/id/LM386-Audio-Amplifier/ but i was wondering if i can make it without the 10k pot as i dont have one.

Question by Kante Tech   |  last reply


Fisher amp problem?

I just got a fisher amp for my stereo system. I was playing music fairly loud when i saw a spark and the music stopped playing. I thought i blew my amp but it acts as if nothing happens. the lights light up with the song and all the buttons do what there supposed to but music wont play through any of the speakers. What happened and is there any way to fix this? p.s. i have a fisher integrated stereo amplifier if that helps.

Question by Thelonelysandwitch   |  last reply


LM386 amp buzz? Answered

Should be an easy question :-) I built my first 386 based amp, and it works great, except for input volume control. Almost every schematic has 10K pot at input (connected to pin 3 on 386). Problem is when I turn pot all the way down I hear buzzing noise, especially if source is off. Also it doesn't cut source volume noticeably so I tried using 10M Pot, and it works except buzz is now super loud. So how would I control volume? 

Question by bratan   |  last reply


Guitar Amp Static

Following up on my other thread with soldering, I managed to get my circuit for a distortion pedal all wired up.  I've got the clean end working, and nothing at all on the distorted end, but I'm not concerned about that just yet.  On the clean end, I get a really annoying buzzing sound, like when you turn the amp on with a cable plugged in with no guitar on the other end.  What would be cause of this?  Possibly outside interference since I haven't actually put this into an enclosure yet?  This is the schematic I followed.. https://www.instructables.com/id/Simple-overdrive-effect-pedal/step2/The-schematic/ and the sound from my amp is similar to this.. http://www.youtube.com/watch?v=ZUeRLC4z8f4 No, it's not the amp that's the problem because it works fine without the circuit.

Topic by MGZero   |  last reply


OP-Amp Troubles

Hey everyone I was hoping someone here could help me with a problem in having. I've been tinkering with some op-amp circuits with the LM386N-1 namely the one I have pictured. I first assemble them on my prototyping station and they work well using the signal generator but when I connect them to a audio line from my computer nothing comes out the speaker I have tested the cable and speaker and they both work so I am at a loss as to what's not working. I would appreciate any help you guys can give me thanks

Topic by juggalo_assassin183   |  last reply


Op-Amp Help

Hi- So, I made the circuit below to make sound-reactive blinky LEDs for a halloween costume (the round thing on the left is a condenser mic). I think I just got lucky that it worked, because I'm no genius when it comes to op-amp usage or design. Now I want to adapt it to control something else that needs a slightly higher voltage than the LEDs. Basically, I'd like the output to swing as high as V+ when the mic input is "loud" (a relative and possibly adjustable level). I've messed around with various resistor values as well as adding or removing resistors in places it seemed like it would help (according to the LM741 datasheet). All to no avail. Anyone out there who might know what to do? Again, I want the mic input to cause the output to go as hight as V+ (9V in this case) when it's loud, and be more or less at 0V when it's "quiet." Thanks in advance, _mykle

Topic by deadbilly   |  last reply


What amp to use???

I recently made an amplifier based on a TDA2004 chip i salvaged from a car radio but i wanted to get more power and so i planned on making a 20w or more version. Problem is, i don't know what chip to use. Can you guys help me? Criteria: 20w or more (just give me the max wattage the chip can carry) non-SMD chip, preferably on those chips that are on a multiwatt-like package min voltage lower than 6v (around 5v or less) and higher than 6v (obviously) load the chip can carry must be 4-8 ohms About the wattage, just give me the max wattage. I've been running the tda2004 for  some time now on 6v only and it's pretty loud, just not loud enough on open areas (rave party, anyone?) Anyways, just tell me the power amps you know of that'll satisfy the criteria or at least close to it. I need answers in 4 days or so, so please tell me ASAP. Thanks in advance!

Topic by beehard44 


Help with OP amps Answered

I'm making an instructable about this circuit, it's a heartbeat detector, it's supposed to beep when a heartbeat is detected. Something weird is going on with the comparator, first of all, the input signal to the comparator seems to get "stuck" at the level of the comparator, like it is an invisible barrier that doesn't allows the signal to cross it easily, this seems to happen with and without the buzzer. Secondly, the comparator "rings", it doesn't displays a clean square signal when the threshold is reached, instead, at the end of the square pulse "ringing" appears. Removing the buzzer or speaker solves the ringing problem.  I tried replacing the buzzer by a 8 ohm speaker, but the problem persists. Then I tried changing the 1k resistor of the transistor by a 10k, but the problem is still the same. I don't know what could be causing this, bad design? A faulty chip? In the second picture it can be seen how the signal "bumps" an invisible barrier when reaches the comparator level, in the third the "ringing" can be seen, the fourth and last picture is how the (previous) comparator signal looks when the load is removed, the problem disappears. Thanks in advance,

Question by Victor805   |  last reply


can stepper motors be combined to double the amps?

I have four stepper motors connected in series to get 12v and more . Can I connect them differently for getting higher amps I think they currently put out like 30 ma each is there a way to increase this amp? thanks for sharing Al

Question by celalboz   |  last reply



How many Ah are car batteries?

I want to know how many Amp hours a car battery has? I need to know how long I can use them for particular things. Also how many Amps will you be able to draw from a moderate sized one? I need to know how much I can squeeze out of them before I start experimenting with them.

Question by The MadScientist   |  last reply


12v DC battery amp measurement? Answered

HI, I have a 12v dc battery and I wanted to measure the amps. Can anyone show me how to hook up the multimeter? Thanks

Question by amantux   |  last reply


Not getting an amp reading from panel?

I am a newbie, I built a panel and I am able to get the voltage but I am not able to get a reading for amps.  Any help will be greatly appreciated. Natalie

Question by Kumachun   |  last reply


Do you add amps together? Answered

I guess I don't understand how amp ratings work. I want to use a 12v 5a power supply for a peltier plate. I am using a 2" cpu heatsink with a small fan attached to cool it properly. I tried it with a 9v battery and it worked but I want to use an AC to DC wall psu. The fan is 12v 0.12a. Do you add the amps together (5.12a) for the total? If so, does that mean a 5a psu is not enough? I don't want it to be too low and draw too many amps and damage something.

Question by Arya42   |  last reply


My Amps! My Amps! *Screams an old crazy man in the deli section*

Yes yes, shhh I want to ask a serious question today. I traded one of my kenwood amps for my parents as their sony surround unit is really shitting out and the sound sounds terrible and the entire control panel on the front is messed up. I just want to know a couple things about the sony to see if I can fix something. The panel, well that's quite interesting to explain and if I posted a video of it you guys would probably think I edited it or something. So imagine this, the bass + and - buttons are beside the treble + and -, two sets of buttons. If you push one of the bass adjustment buttons, it glitches and turns the treble for example, up or down randomly and doesn't do what I wanted it to do. It's like this with all of the buttons and seemed to have happened after we moved here. And I know it didn't get banged around because it was transported in the back seat of a car on blankets to the new house and carefully carried in by me. If I say try to use one of the surround sound adjustment buttons it glitches out and acts like I hit another one that's beside it in any direction. Hard to explain but I'm just damn confused as to why it suddenly happend (dry solder connections?). Damn this post is long and it's only half done...lol. Bad sound, I will not tolerate it under my household, but on the other hand it was a $400 unit back 5 or so years ago and I KNOW it used to sound good, with a such a profound richness of bass that just punched right through you. Now it sounds like shit, the sound is garbled, distorted when turned up, it's not really noticeable until you turn it up fairly loud. I have/had my technics tower speakers hooked up to it and they sounded like shit when I turned them up, yet on my kenwood they sing like the wedding singer days. Any ideas nachomoma? I'll add another note that for most of it's life it's been hooked up to a pair of 250 watt (peak) optimus floor speakers and whenever we played it, it got HORRIBLY hot and warped the top a bit when it was on, enough to push it in and make it spring back up again with quite a force. I liked this receiver a lot and would like to use it again, but I don't know where all these "degradations" came from and despite my useless amount of amp questions/bickering's about I would really appreciate any ideas from you guys. Thanks.. -Punk

Topic by Punkguyta   |  last reply


Can anyone tell me step by step instruction on how to convert an old phonograph tube amp to a guitar amp.

Can anyone tell me step by step instruction on how to convert an old phonograph tube amp to a guitar amp. It has a 6bq5 power tube 6X4 rectifier tube, and a 12aX7 pre tube. Can anybody please tell me how to do this. You would be so appreciated. I have soldering skills, but not too much electrical knowledge. I know what resisters are, I know what transformers are, I know what capacitors are, and I know the very basics of their functions, but I can't understand how to tear it down and make it a good guitar amp. I want to remove the feedback circuit so that it will distort naturally. I would also like to modify the equalization and tone to better suit guitar amp. Please help. You would make me so happy. I cant afford to buy a good tube amp, and this is my only hope of making a great sounding amp. Thanks so much. Please be as detailed as posible in these step by step directions. You are awesome if you can help me.? Thanks The amp is from a 1959 Newcomb model R124V phonograph with an inboard 6"X9" speaker. It works perfectly with no crackling knobs or nothing like that. The amp is super clean and well cared for The tubes inside are 6BQ5 FROM AMPEREX BUGLE BOY. The rectifier tube is 6X4 from sylvania, made in USA. The 12AX7 is made in Britain, but I can't see a name on it. I have many spare 12ax7's lying around though. Thanks so much in advance.

Question by meman-mark   |  last reply


how much current needed for a bilc pump to operate, will it operate with say 2 amps 12v PSU? Answered

How much current needed for a bilc pump to operate, will it operate with say 2 amps 12v PSU? I have this pump, i can barely spin it by hand and it is not working by poering by a 1 amp psu, perhaps I demaged it while testing with 24v Ac . thanks

Question by celalboz   |  last reply


URGENT! Question about in-line audio control between amp and speakers? Answered

I have a unique project that I am almost finished with, but need to make one last adjustment to. I am running a 3.7W Class D Audio Amplifier. The amp has two outputs. I need one to run as designed (controlled by my iphone before the signal gets to the amp which will be set to almost max volume). I need to then control the other output channel to reduce the volume. Any suggestions? It seems like I might be able to just get an inline control out of an old set of earphones, but I am not entirely sure. I always assumed (and pardon my ignorance if this was a foolish assumption) that the buttons in my iphone earbuds actually signal the phone to change the volume, and isn't really "in-line". So, I don't think those would work. Would an old set from Goodwill work for this? I have seen posts where others are asking similar questions and the answer seems to be a 1K Ohm Pot (which are apparently really tough to find). Since I have a 3.7W amp, perhaps a 10K Ohm Pot will work (people have said this doesn't work well for their headphones).  To summarize: 1) Will adjusting one output channel on a two-channel amp work? (or will the increased resistance simply close off the channel and pump all the signal to the other channel?) 2) If this will work, can I use a 10K Pot? 3) If not, will an old-school in-line volume control from some headphones work? Sorry for all the info...trying to be thorough! Thanks a ton for any advice!

Question by WhiteTyrone   |  last reply


boost volts deflate amps? Answered

I recently came to know about a "mintyboost" from "steveastrouk"( a very helpful and trusted member of instructables).It boosts up volts while bringing down amps very much like a step up transformer.Well I've got 2 AA rechargeable batteries rated 1.2 volts and 1900mAh.So here's my first question-I connect these batteries in parallel and they give out a total of 2.4 volts okay fine....but what about the amps?will they get added up like volts and produce 3800mAh current?The latter part-I need to boost this 2.4 volts to 5 volts by bringing down the amps(any value is fine as long as its above 0.7 Amps).Could you please give me a specificated instruction on how to do this?If to use a "mintyboost"what software should I use to calculate the required values and......... the rest...... Pls don't think I'm lazy.I really want to do this so badly...

Question by Adarsh_tronix   |  last reply


Whats Better Volts or Amps? Answered

I know the two are completely different, just so you guys don't leave any I'm an idiot comments.  I was wondering if anyone knew what makes a better electromagnet for my coil gun.  Should I look for higher amps or just as many volts as I can find

Question by jj.inc   |  last reply


Power supply volt/amp question?

Hi, My power supply is ac 110v to dc14V 700ma and I want to connect in parallel 2 strips of 4 led (350ma - 3.2v each)  Total voltage per strip 12.8v with 350ma each. I would like to power these leds at 2.5v each (total 10v)  and at around 250ma each. I installed a buck converter at the output of the power supply to reduce voltage at 10v. Will the amps also drop as voltage is reduced or will it stay at 350ma on each strip?  If it does not drop, how could I reduce amps to about 250-275ma? Thanks

Topic by Lion_Heart   |  last reply


Sending more than rated amps through a switch?

I know that if you use a switch or a relay and send more amps through it than rated, it can cause the contacts in the switch to melt. My question is what if you only open and close the switch when the amps being sent is less than the rated max and then send more than the rated amps but don't touch the switch? Will this still cause the contacts to melt/explode the switch? I'm asking because I currently have a circuit that works as described above and the switch still works even after many uses. Is this because I only operate the switch when the amps are less than the rated max for the switch or is the switch going to die soon?  Thanks in advance :)

Question by WilfredS3   |  last reply


d2822 headphone amp build

I have a d2822 op amp and i want to make a headphone pocket amp out of it but i dont know how to wire it. can anyone help?

Topic by heyytraviss   |  last reply


Equalizer for phono input to amp

Circuit for converting an MP3 player output to input for a phono input on an amp.

Topic by knorrisster   |  last reply


help with lm386 OP amp?

I'm running my guitar's output signal into an Lm386 op amp to light up some LED's, but the amp puts out a constant signal instead of just when I play. What can I do?

Question by spinynormann   |  last reply


Making a temporary amp with mosfet?

I don't know how to make a amp for my 4ohm 125watt subwoofer? I got heatsink and some Toshiba mosfets.

Question by ShaneR66 



50W amp 60W speakers? Answered

Ive got a 50w dual output Bluetooth only amp, I've also got Two 60w speakers would putting the max volume into the speakers damage them if played for a while. The speakers are 4" and slightly distort at max , could be from slight under power , the amp is rated at 8v to 24v and I am using a 19 v 3.16 amp laptop power supply Speakers 8ohm 60w  Amp dual output Bluetooth only 50w x2 Amp power 8v to 24v

Question by bonze77   |  last reply


Power supply amp measurement?

My power supply says it can supply 12 Volts @ 10 amps.  It used to power 2 linear actuators drawing max 4.6 amps each, but no longer does. It still supplies 12V measured by multimeter. Is there an easy way to figure out how many amps it now supplies?

Question by thisisted   |  last reply


Need Help With Amp Instilation

I recently aquired a Infinity 311a Amp and am wanting to install it on a 1994 Chevy Silverado 2500. i can get any wiring i will need i just dont know what to start with  

Topic by torquerat   |  last reply


Power amp clipping problem?

I recently bought a Pyramid PTA150 1500 watt power amp, and its clipping led's always seem to be lit when my mixer is set to half volume or higher, even when the amp is unplugged. Could they be powered from the input voltage when it is high enough? Is it bad to push my amp when they are lit? and it has a high volume cooling fan so I dont think it will overheat when pushed.?

Question by macwhiz   |  last reply


How Op Amps work? Answered

I was wondering if anyone could explain how an op amp like the LM741 works. I don't mean I want to know what's going on inside it, but more along the lines of "how can it be wired up?" and "what could it be used for?"

Question by tylervitale   |  last reply


Question about speakers and amps? Answered

Okay, so I want to build a set of two-way speakers. BUT, I'm still confused on this one part. Do I need an amp, or some kind of receiver for them to work? Or can I plug them straight into the device? Thanks for your help, sorry if this is a dumb question.

Question by Zem   |  last reply