alan monro

Fantastic Amps Dirt Cheap

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I have been searching for good high quality high power ,ultra reliable ,low cost amp for a long long time .I had nearly given up trying to find such an animal.

I have finally found them after searching and asking around ..

I was looking at the !00w ic TBA7293 ,half a dozen extra caps and resistors and that is it .

Just look up the ic and you will find cheap (in price) amps already constructed .eg 250w amp

$20 postage free ,  555w for $50+$10 postage , all you add is the power supply and away you go.

It would be so easy and cheap to add extra channels to HT.

The Tube mob also like them as they say the amps are warm and detailed also distortion free.

I will let you know how i go .

Now i can those dam subs up and running again .!!!!........................Alan. :dancing:

 

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Alan,

I have always wondered about trying out chip amplifiers, but just one of many projects I have wanted to try. They are super simple to build and from what I have read, sound pretty good. Did you research any other chip amps? IIRC gainclone was what I was searching for when I was looking into the idea. What size power supply are you planning on Using? Don't forget about god heat sinking. Those little chips dissipate a good amount of heat IIRC.

Go big or go home right?

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Gooday Todd,

Have been watching the incredably freezing weather you are suffering with. I can not beleive people traveling to work in it .

On tv it showed cars sliding all over the place compleatly out of control.

It is nearly Spring over there now so the weather should start picking up.

The amps , Just call them a blessing that not many people have gotten on to .

I researched many other ics for a long time and found these to be the pick of the bunch .

I would say ......Gone are the days that people construct thier own amps ,............. it is finnished.

I wouldnt make that statement unless i meant it. They have finally put a fantastic amp on a chip .

With these amps the more ics to share the load (one master and slaves) the cooler they run .
The 3 ics amp just needs 1/2 Ib -1lb of heat sink .

Did you read that they are protected against o/p  shorting ..

I will use the triple ic board 250w   ($20) The power tranny 200w , amd about 40,000uf of caps.

The idea a sub amp doesnt depend on rms power during music due to the intermitant nature of base or in HT mode , explosions or rumbles . The sub must have a high peak output that doesnt overload ,that is why 40, 000 uf  or higher caps...........................Alan

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The weather has been nice the last couple of days, but they are saying 6-12 inches of snow tonight and tomorrow(15-30 cm to all the folks using metric out there(the measurement system that makes sense)).  Spring will be here soon enough though.  

 

Sounds like a plan Alan.  You will have to get some pictures for us.  We are void of projects on the forum currently!

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Right you are Todd,

As soon as the amps arrive from China I will take photos and describe how to replace a dud sub amp with a new type of amp .

The only trouble will be trying to work out how to put the images onto the net.  By the way, I will be using the original terminal block and the sub amp .

I am particually interested in replacing the badly designed amp in my Klipsch sub .but , i will do the other sub first ....

Getting too hot at the moment , better jump in the pool to cool off .( don't you hate me ????) :pukedesk: .....Alan

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I can't say that I hate you, but I am jealous!  This is what yesterday looked like for me.  Plus lots of wind and tall snow drifts.

 

147317C6-7622-46AA-976A-6715992AEE24_zps 

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LOL :madrofl: Todd , I liked  the new name of where you live !!!!

What stops the cars from just sliding off the snow into the sideing ??. The picture you sent looks very cold and grimm . Seeing that I have never been amongst snow I dont fully understand  what it would be like driving in it , I looks bloody freezing ! I think that it would take a lot of skill to stay on the road. ...................Alan.

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I was a passenger at that point, but it's not terribly bad once you get used to driving in it.  Just have to drive a little slower and brake a little sooner.  All wheel drive or 4 wheel drive helps too.  That was a pretty fresh snow though.  The state and county plows to a pretty good job at keeping the roads cleared of snow, but when we get dumped on, it isn't always in a timely manner.

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This is one of the amps I purchased 35v-35v power supply 250Wrms 4ohm

I have to work out how to attach a led on to clipping  pin 5 of the ic ,  .There are 3 ics with pin 5  ???? Nothing is easy nowa days!!!.

Also how the configure the standby and have a visual indicator of such .Looks like sby pin 9 low sby on and pin 9 high sbyoff.

I will work that out as I am constructing the animal .

Ordering my 300va 25v-o-25v Toroide now $70. the cheapest I could find . there is some a bit cheaper but i dont trust the sites.

Just have to wait for the slow boat from China now.

Working out if i will make the amps for the subs external , ie, to sit on the top of the box . better cooling more reliable over the years , thermostatic fan cooling ?????????????????.

I need 30 cups of coffee at the moment !!!!!!........Alan

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This is the power supply 35v caps 6400mf 105*temp 35 amp bridge.

I will drag up the tranny when I have time.......................Alan

Working out the heat sink , the ics thermal isolater . mica, silicon etc ,

and the enclosure that sits on the  box .(everythings runs cooler)

I think I will put in a watt meter to go with the clipping circuit ????Maybe a remote vollume control???...........................Alan

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Can a larger power supply be used with those ICs?  When I was looking at this idea years ago, I thought you could run higher voltages for more power.

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Todd , No , 30-37 per side is max while using master and slaves .
need more power ,use more chips .Such as the 7ic 550W $45 + $12 shipping
$57 for over 1/2 KW . That is not bad. have a look at this beast  !!!! This is my next project to replace my badly designed and built ,shitty  , Klipsch bash amp..................... Alan .            ps fan forced cooling a must$(KGrHqQOKkQE3uc,s0ELBOEonefZNw~~_3.JPG

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Still flat out designing , and checking parts and translating Chinese parts manuals. and drinking coffee  Will have pics and details soon , i hope ..........................Alan

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Good to hear Alan.  How are you doing the Translation?  Google Translate?  Sounds like too much fun for me!  Very interested in hearing your opinions on how these sound.

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Gooday Todd ,

Google translate is very good .Its a shame that google grammer isnt avaible. I scratch my head trying to work our what they are saying . I get the general drift of it after a few hours .

Just purchased  a electroletic capacitor tester from China . Trying to translate the manual .

YZ bench type and about 7lb . tested it and found it Quite accurate .It will test to 2KV or down to 2V. The clever thing also will test the voltage rating of a electrolytic without damaging it .I am not to sure how it does that but it worked . It also tests voltage regulators , diodes and transistors .
The wiring is a bit rats-nest, No earth on the high voltage and mains transformer , 2,000V passing through ordinary hook up wire!!! , It is not double- insulated . It needs a bit of TLC , about a day of enjoyable work . It gets a bit hot so i will vent the case and add a fan to it . IT has a very good safety feature The tested cap is discharged through a series of relays and large power resistors after testing . I will take pics as i go and put them here .
The thing is it works perfectly the way it is. It has a 2year warranty .
I will have to locate a chart to tell me the acceptable leakages of all the different electrolytics.............................Alan
user_online.gifreport.gif quote.gif

 

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You would not believe it ............................My new computer and monitor got zapped by a lightning spike and is now down the tip . I am using my betterhalfs laptop at the moment untill she springs me . she doesn't like me using it because said i am too dam unlucky.

2  lightning zapped computers in 1 year doesn't really mean that I am unlucky ..................................does it?

I am going to make 240v mains cleaners that should protect my computer .

I pick up the new computer and monitor next Thursday.

I am going  to start to put together the HT sub amp project and post photos

Better go as I can see lightning flashers in the distance now. ....................................................ALan

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I was just going to say that I thought you just had that happen. I wouldn't call it bad luck as much as unfortunate coincidence.  Looking forward to some photos Alan.

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Todd ,I have not left the country.  :Jim:  I have spent months getting the best and cheapest parts that i could find, Have had 40,000 cups of coffee trying to work out broken Chineese instructions .i have layed the parts out and tested my ideas and modified where the manufactures have made errors , in many cases there just wasnt any info at all from the manufacturer or net .I photograthed all the parts from the start of the universal Sub Bass Amps project ,( I am making 2  identical amps)  .Still have to work out how to put the photos here . The forum keeps saying the files are too big .I was trying to download 1.2M

Anyway ,The aims achieved so far------------ 250 Watts continuous RMS(Very large Heatsink  and power ics very efficently coupled )

                                                            350 Watts Peak  overlarge Toroidal Transformer and 40,000 uf caps 

                                                            Active clipping protection for amp and speaker, front panel indicator

                                                            Remote control off- on and vollume control  , at night time when people are asleep you will not have the the sub automaticty turning on .

                                                            Vollume level window display.

                                                            Adjustable low frequency cut off filter  20-140 (i think)

                                                            Very easy and cheap to make ,readily avaiable parts

                                                            Looks and sound fantastic

                                                            Easy to construct. As small as possable.

                                                           No real need for a letterd front Panel (but for the hell of it I made one}

                                                           AUTOMATICLY AND WITH NO STRESS WILL WORK DOWN TO 1 OHM SPEAKER

                                                          

                                                          Extreamly stable with long leads to speaker , or speakers (2 ,8 or 2 ,4 ohm )

                                                           I fashoned the amps in the form of a 6"black cube because............................................... I like black 6"cubes.................More to come ..........................Alan

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Looking at it ,I am afraid that I am making this a little complicated for a lot of potential constructors , so I am dropping the remote on off , remote vollume control and display  (dont realy need them), this saves approx $40 , ( 12v s'by transformer motor remote vollume  , regulator and filter circuit and 12v-230 mains rated relay) and makes it so much easyier as it was too jam packed , I will also change and,simplify all the connectors .I will make a new front panel to suit .metal work is now simple , no square hole to make,  I hate making square holes in metal or perplex  Yes , the front panel is 3mm  0r 1/8 "perplex  . I will describe the  front panel that any one with a lazer printer and *FRONTDESIGNER* SOFTWARE can make  later on ----Easy is the word :Jim:!!!!!!!!! .............................................................Alan

 

The unit has clipping protection with manual reset .

 

The idea was to make them bullet proof .

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I have been busy , the camera has died and that has delayed me , ordered another , Panasonic fx200 . or Leica V-Lux4 same thing different badge and they are made in the same factory.

Neally finished all the amps , designed and building a easy to make ,crash hot circuit board holder at very low cost, will give details for any body that wants to copy . also , gathering infomation on making a studio quality recording microphone dirt cheap . any body interested i will give all details . and photoes of the condenser mike. must go ,late at night ............................Alan

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You have the worst luck imaginable with electronics!  Two things die in one thread!  Still interested to see these amps.  I really want to do something like this, but I just have too many excuses :P  I really should after spending time in school for electronics. Refresh my brain!

 

Any details on the DIY condenser mic sounds awesome.  That'd be a fun one to try out!  Do you construct everything, or is it more of a kit?  

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Gooday Todd. :gayhaaay1:

I am not doing a kit  , so far   The mike is going to be a condensor type , I have found a Panasonic WM-61 miniture insert , iTjust needs a amp and battery real response 2cps to 30, 000  very low distortion and fairly low noise. Sent away for some ,  about fifty cents each , yes it compares to $1000, commercal mikes . As a mater of fact it can be used as a flat refferance mike .I kid you not , have to research this more ..................Alan

Pics shortly

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