At 22 watts its pretty loud

[donald stringer]

I "ve been doing a hack on my project chip amp KA6210ah [ALTEC LANSING multimedia subwoofer] and after getting the useless parts out of the way and going into my cab, 22watts per channel is freaking loud. I mean at bedroom level its obnoxious. I cant wait to tame it with a simple pre-amp. For solid state  such as it is its got pretty good tone.

[donald stringer]

I need to do a mini build report on this. You can find these things for cheap every where and  not much actual building to be done.

[JKowalski]

I googled the chip name and didn't find anything? What exactly is this?

[StephenGiles]

I "ve been doing a hack on my project chip amp KA6210ah [ALTEC LANSING multimedia subwoofer] and after getting the useless parts out of the way and going into my cab, 22watts per channel is freaking loud. I mean at bedroom level its obnoxious. I cant wait to tame it with a simple pre-amp. For solid state  such as it is its got pretty good tone.

My first amp in 1963 or thereabouts was a mighty 10 watt Watkins Westminster. Driven by a Strat through a tape echo box (not mine - that came 15 years on!) that was loud too. I suspect that it had a very efficient speaker which is half the trick.

[drk]

an efficient speaker makes all the difference! i play in my bedroom with a lm386 amp(i think it has half a watt or something) connected to a good speaker, and it's really loud!

[Mark Hammer]

When I used to read the audio mags religiously (taking out my prayer mat and bowing to Len Feldman and Julian Hirsh 5 times daily), 4 watts was considered to be a sufficient amount of power for "room-filling sound".  Of course, what fills a room with realistic levels of listening music when it's carpeted and no major construction is taken place beside your home is different than what appears to fill a room when there is an ambitious drummer right behind you.

Still, when the speakers and accompanying cabinet permit the full pertinent bandwidth to be reproduced efficiently, a "mere" 10-15 watts can be surprisingly loud.  Or, more to the point, make 50-60 watts seem surprisingly unnecessary.  This is precisely why so many consider the old Deluxe Reverb (22W from a pair of 6V6s) and the Marshall 18W to be their "desert island" amps (assuming one has a power generator on said island!).  Low enough power to be easily overdriven at tolerable volumes, yet loud enough to handle club gigs.

It is also worth noting that the power rating of solid-state chip-based amps is often misleading.  Not in the sense of those $10 computer speakers that have "360W PMP".  Rather, the stated power rating is often one based on the properties of the chip with a given load, given power supply voltage, and given PS current capacity.  Whether those "peak achievement" properties are adhered to can be quite another thing.  You'll find a spate of so-called "practice" amps that use the TDA2030 or 2040 chip with ratings anywhere between 10W and 35W.  Moreover, the assumed output power is a function of power with a given amplitude of signal to the power section, and front ends vary with respect to what that final signal level to the power chip will be.

[donald stringer]

Here it is http://www.alldatasheet.com/datasheet-pdf/pdf/69376/KEC/KIA6210AH.html  According to the spec it was desighned to be used in car stereos which shows the the gears of inventive minds works at altec lansing. They probably could have used any one of a hundred different types to do what they did. Whats more interesting is they  used a compandor [572 ] andone quad lm324 to do the low pass filter nec. for the subwoofer. I just followed the pin out of the chip/ isolated the inputs/ and alligator clip my guitar to the input/ and cut the speaker wires and twisted both pos and neg. together and plugged it in to my cab. It exploded with sound.

[donald stringer]

I have two more projects one is a an old cd player with its own power amp. I have to gut the cd turntable isolate the input points etc.Theres one more project thats going to be a bit more involved. Its a your typical stereo cdplayer/radio/etc/ but it has an module that you can connect and preset upto 5 graphic E Q positions. This module has an input and its where I plug my guitar into therby accessing the power amp and EQ. I am going to try and take everything out of the signal path that would effect the signal. By the way you can almost plug your guitar into any input point and get sound/just at different levels

[donald stringer]

While I"m on the subject of this altec lansing proj. heres an older altec lansing tube powered comp. amplifierhttp://www.schematicheaven.com/effects/altec_436c_compressor.pdf

[mac]

I'm developing my own SS amp, I do not know how much power it has, there are 7 watts across a TIP41C in class A mode, but it has enough volume to wake up my whole building!

The 5 watts of my VJ are to loud for a small bedroom without acoustic isolation/anti-reflex.

mac

[R.G.]

As in all things electronic, first read the spec sheets.

In this case, the speaker spec sheets. All modern speakers have power efficiency numbers in their spec sheets. This number is always given as sound pressure level (SPL) for one watt of drive into the speaker.

It is common for this number to be 90 to 110 db SPL. So even ONE watt delivered to these speakers is as loud as an air powered jackhammer and many machine guns.

This is another consequence of the human ear's log response to sound pressure. The low pressure, quiet sounds are heard clearly. A 1W amp is only 1/4 as loud as a 100W amp for equal situations otherwise.