BA6110 Vs BA662

[sir_dss]

Hi...

Building my first x0xb0x and wondering about the advantages of the BA662.

Thanks,

David Scott Stone

[phono]

none at all, do a search on the forum for subatomics tests

[hamburgers]

Hi...

Building my first x0xb0x and wondering about the advantages of the BA662.

Thanks,

David Scott Stone

you get to pay more for it

[Luap]

Being the curious sort, I decided to try a BA662 for myself.. Not that I doubted what anyone here said. But sometimes I just gotta prove it to myself you know!
I installed it in one of my x0xb0x's.. And sure enough, it made no discernible difference what-so-ever! Maybe there is a bit less gain? Which ties with what I have read elsewhere, although I didn't measure it.
The lads here were indeed quite right. The BA662 does not appear to contribute in any way to the 303 sound, so is not worth bothering with in my opinion.

Incidentally, it is a special colour dot selected variant of the BA662. But to my knowledge there is no difference, besides tighter tolerances and a yellow splodge on it.
It was "New old stock" from vintageplanet, for anyone interested. But cost roughly 30 times what you might pay for a relatively common BA6110..

[e:pp:ik]

Those dotted versions are selected chips because when you need to combine multiples in a bigger synth like, say, a Jupiter, you want to have closer calibrated ICs. In that case it does make a difference. In the context of the x0x though, there only one of these ICs so going 662A and/or dotted is simply a luxury addition to the synth.

I've run both on mine too and prefer the 662 simply to keep the synth period-correct. Like other have said, it's only an audible factor in terms of (an insignificant amount of) gain.

[Luap]

Yes, I figured the colour dot versions were about calibration and consistency of performance when used alongside other 662's. Or something along those lines!
They were all that was available. Plus they were unused parts, instead of pulled parts. So looked to be worth a go..

When I posted that comment in this thread a couple of days ago, I had only used it with the BA662 for a short while. Now that i've had a little more time with it though.. Perhaps I am noticing something after all. But it is not a difference of the general tone of the x0xb0x (which is what most tests understandably focus on). I am quite convinced the tone is unchanged by the 662. If there is a difference, then it is only slight, but the dynamics of the x0xb0x seem a bit less peaky (even after compensating for the slight gain loss). A lot of x0xb0x's I hear (including one of mine) are a little snappy on the attack of the note compared to most real 303's, particularly so with accented notes. And this exaggerates some of those note on pops or clicks that can be present. I've a feeling the BA662 helps some in that department.

But again, any differences are so slight that we're really splitting hairs at this point, and im probably well into placebo territory too!?
It's not a "must have" part by any means.. There are bigger differences to be had from a little experimentation with the key transistors. Like the Q11 mod/tweak for example.