Sparkleboost/Blue Magic build report

[Bagge]

I finally finished my Sparkleboost/Blue Magic build. I've had some noise issues with this thing, but it's at an acceptable level by now. At first I had constructed both circuits + Millenium bypass on one veroboard, but there was a lot of noise on the BlueMagic part. So I cut it off and redid it on a new veroboard, and changed caps to ceramic. That did the trick, but I recommend to be careful, when boxing two effects in one. It can easily generate noise. I do like both effects very much, but I'm gonna work a little bit on Blue Magic, as it is too bright for my taste. (I put a 4,7uF instead of 6,8uF). The toggle switch is for the open sound between 10K and 22K. There is not much difference by now, though, so I'll have to try different values there.
During the process I managed to burn 3 BS170, they seem extremely sensitive?



I can certainly recommend both builds; they are very nice sounding boost/overdrive circuits.

[Paul Marossy]

I like the Blue Magic, but my only complaint about is that it can tend to sound kind of muddy with my setup...

[Karmasound]

I built the BM too

But I put R11  on a 20k pot. But with it all the way down it sounds really open and bitey it's not muddy at all compared to when I turn it up.

[hilbi]

Reduce the 6,8 cap to remove some mud without losing the smoothness of the BM.

In my opinion the open control sounds fine on low drive settings but not on higher drive levels. So the open mod is not really a solution to get away from mudiness.

[Coriolis]

Hey nice build!   Do you have the boost after the Blue Magic, or vice versa?
Did you try both?

C

[Bagge]

Thanks

The boost is in front of BM. I have not tried it the other way round. Maybe I'll try it sometime. I really like this boost. Thanks to Dragonfly for this circuit. There has been some talk about the effect of gain knob. Although I use SS amp, I definitely find gain knob useful. It can add some nice bite to your sound.

There is still some tweaking to be done on BM. But I certainly hear its potential.

[Paul Marossy]

Thanks for the tips on reducing the muddiness in the Blue Magic.  

EDIT: Uhh... reducing the 6.8uF cap? Do you mean the paralleled 3.3uF caps?

[Bagge]

Holy... I just discovered why my BM was so brittle. I tried increasing C2 (6,8uF) for more bass. Not even 10uF made any noticeable difference. Then I went through all caps, and it turned out, I had put in 22pF instead of 22nF at C7. Now it has much more bass. Tone control also works much better. It is however more muddy, and that led me to think, that you can clear up the tone by decreasing C7. It does also decrease overdrive level.

Anyway, thanks to J. Nagy for this circuit and thanks to everybody who has helped out.

[Paul Marossy]

Ah, I see what must be going on here. The latest GGG layout has a C2a and a C2b cap, both 3.3uF and apparently, C7 is the 0.022uF cap that isn't labeled. Now I'm tracking...  

[hilbi]

I use a 3,3uF and a switchable 2.2uF paralel cap for C2.

That way and with the mid boost you can create a ts bass cut/mid boost, but it is both switchable and very versatile.

[Paul Marossy]

hilbi-

Interesting. Thanks for sharing that!