Plan to make LM 317 power amp

Dear Mr. Admin and everybody,
I have a Plan to make LM 317 power amp with AD 712 opamp,
The big question is, how much power i ll got,
since i want to drive my SL 6 Celestion speaker ;-)
 

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Your power is limited by the current sink (about 1.25A) and the supply.

The SL6 is not an easy load (I used to own a pair) and so if we assume a max voltage swing from the -/+12 volt rails of around -/+ 9.5 volts that gives us around 6.7 volts rms into an easy resistive load.

I would guess realistically around 4 to 6 watts rms into the SL6. The level might be even lower at high frequency.
 
Thanks for your explanation Sir,
So, what s the simple diy amp that can drive SL6 Speaker ?

Well your limit here is the very low supply voltage. The SL6 is only 82db/1watt meaning it is very insensitive.

Have a look at post #20 here which deals with the SL100 (I still have those). The SL6 is even worse for efficiency.

How much headroom is needed

So before you can decide what amp to build you need to determine what power you want. If you don't play it loud then a few watts might be enough.
 
You need something much better than a TEA2025 and 24 volts is probably getting a bit high for the LM317. The problem with the LM317 is its limited current ability.

An LM3886 chip amp would be good and with it running on around -/+ 25 volts.

An LM1875 is very easy to use and would be OK (decent levels) running on -/+25 volts. Lots of kits for all these.

Both these would also run very cool when idling.
 
Your follower and the 317 circuit you showed initially operate in class A, which severely limits the output power and causes a huge dissipation: your MoFo will dissipate around 100W, with is difficult to manage.
Some of the 317 circuit examples I proposed operate in class B or in an improved, channel-correlated class A for a reduced dissipation and higher output.
In class B, as a 317 can deliver ~1.7A peak when properly cooled, you could theoretically arrive at 12W sine power; more realistically 10W.

But the best solution is to opt for a dedicated chipamp: this section contains many usable examples, based on good, commonly available ICs
 
I think you need to draw up your own specification for what you want 🙂 Things such as whether you want Class A (hot hot hot), how much power you really want, and having decided that you can then look at what sort of power supply and heatsinks you need.

The follower has a voltage gain of slightly less than 1 so you need a preamp stage. It also has a massive power dissipation of about 160 watts for a two channel stereo set up. Massive heatsinks, massive power supply... that's not my thing at all 😉

So think what you really want first.
 
(I bet you know this but for general entertainment🙂

Your follower and the 317 circuit you showed initially operate in class A, which severely limits the output power...

Worse: good class A (choke-load or push-pull) approaches 50% efficient; this constant current scheme is 25% efficient at best.

In other words, you need twice as much stuff to get a specified output. Transformer. Heatsink.

I've seen it for a headphone amp. (SWTP) And thought it wasteful. Never seen it seriously proposed by an able designer for loudspeaker duty (I'm sure it has been done).
 
It isn't even the worst possible option: a resistor-loaded SE manages to do even worse.
However, this doesn't seem to rebuke members, see one of the well-loved DIYaudio forums....

Let's hope this doesn't give new ideas to the OP.....