fjl4215/4315 VS MJL4281/4302

Hi folks , I'm finishing two channels of the apex b500 amplifier.
originally both on this amp and on many others I have used the toshibas 2sa5200/2sc1943 pair but due to a shortage of them in my region now I am faced to use the fairchild's analogs
which are the FLJ 4215/4315, can anyone say their opinion about them , the datasheets are the same , even more the fairchild editions have higher CE voltage and higher amperage.
Will they be just as good ?

Otherwise I have to use the ON semiconductors MJL4281/4302, I have heard that they are good but they also cost bit more than twice the price for the 5200/1943, but will they sound twice as good ? :D:D

In other words I mean is it worth the additional price ?
 
Hi folks , I'm finishing two channels of the apex b500 amplifier.
originally both on this amp and on many others I have used the toshibas 2sa5200/2sc1943 pair but due to a shortage of them in my region now I am faced to use the fairchild's analogs
which are the FLJ 4215/4315, can anyone say their opinion about them , the datasheets are the same , even more the fairchild editions have higher CE voltage and higher amperage.
Will they be just as good ?

Otherwise I have to use the ON semiconductors MJL4281/4302, I have heard that they are good but they also cost bit more than twice the price for the 5200/1943, but will they sound twice as good ? :D:D

In other words I mean is it worth the additional price ?
In general you will find that a 2pair output stage using MJL4281/4302 has a very similar SOAR to 4pair 2sa1943/c5200.
Look up the datasheets and see max Ic @ 50 to 60Vce

The double of device cost is compensated by needing half the number.
 
Fairchild seems to have clones of all the old Toshiba parts, it's great. Perhaps they bought everything from them when they discontinued their entire transistors range.

Are you sure? Although Toshiba has discontinued most of their discreet semiconductors, 2SA1943 & 2SC5200 look to still be in production for the time being. I would be more concerned of the Fairchild parts becoming immediately discontinued if the buy out by ON Semi is completed.
 
so if I would use 4 pairs of the mjl4281/4302 for a total of 8 devices like i have now only with the sa5200/1943 I could theoretically almost double the amp's power output given that the psu can uphold that and the driver stage are also up to the task?

but given that their base drive is probably no more than that of the 5200/1943 i'd say the driver stage wouldn't feel much difference from driving either one or the other ?i guess its pretty much up to he psu then.


as for the semiconductor industry , but why would it be in their interests to kill the diy audio folks chances of transistors? I mean how many people buy from them also how many more blow up thousands of devices while learning and buy thousands more , I'd say that's business , or is there a deeper though under like phasing out the older transistors and making new ones so that one could not repair an older device and would have to buy a new one ?
 
ok but there is a big electronics industry in the world which as one of it's subforms produces all kinds of audio amplifiers and related audio gear so they can't just stop making transistors hat are best suited for such applications as the market is out there with or without the diy folks right ?

so are you saying that they will simply deny the devices to the consumer market but supply them only to big factories etc?
 

wg_ski

Member
2007-10-10 5:21 pm
They won't be unavailable, but the market is consolidating. In a couple years time, there may be only two or three device families available. Perhaps just the C5200 or some derivative like the FJLs and the MJ2119x and not much else. A couple of different packaging options as well, but only a handful of types. Back in the 70's there were dozens of options, most of which are obsolete. In the 80's perhaps even hundreds - everybody and their dog had a dozen different device families, and most are NLA. In most applications you can replace pretty much any older 100 or 150W high fT type with the Toshiba or Fairchild, any MT200's with current production Sankens, and the 4MHz or lower parts with the 2119X's. With the technology fully matured, thee really is no need for more than a handful of parts from as many (or even one) supplier.
 
The worry? whole consumer audio industry is moving to surface mount parts that take 20 year old eyes, ultra steady hands, and a $10000 wave solder machine to process efficiently. Also there is a big movement to class D and T amps, RF devices that howl like dogs in other equipment unless effectively neutered by packaging, another barrier to diy audio. You can't experiment with the enclosure on it.
Another consideration is pricing, When a commodity is only sourced by two factories, the pricing gets very chummy. Hint- buy now, there are 4 ligitimate factories and 10 counterfeiters.
The switching power supply movement is bad enough- those things will burn your hand off or stop your heart if you make one stupid mistake. And how are we supposed to learn without stupid mistakes?
 
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I agree with you on some points and on some I disagree , the tendency for people to become selfish beings both on a individual and also on corporate level is bad but progress and advancing technology in it's self is not a bad thing, I mean changing tubes in a socket is even easier than soldering transistors through hole but does that mean we should have stayed at the tube level till this day ? ofcorse not , and we also must admit that the majority of people don't have absolute hearing (absolute pitch) so I do believe that a well built class D to them would sound much like any other well built topology if it's working correctly with a good enough signal.


as for the smps , i have built some myself , they do offer higher power for less weight and size, yes some drawback as always.

well i got the fairchild transistors , soldered them in le's see how it goes.