D*A*M - Sonic Titan ( DAM )  [traced]

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davec69
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Post by davec69 »

I just finished this build using the McElroy layout, above. I went with the 2N3819@4.6v / LM386 version, everything else is the same as on the layout.

I seem to be having the opposite problem of some of the earlier posts. My build sounds great. Gain-wise, its perfect, but, it's a little too bright. When I turn the tone pot fully counter-clockwise, I'm just about to hit the sweet spot when I reach the end of the pot travel. As I bring up the tone pot, it just gets brighter.

What adjustments can I make to add more low end to round out the sound?

An example would be if you had a stereo, with only a treble knob, and no bass knob. No matter how much you raise or lower the treble knob, I doesn't put in the missing bottom. I need to somehow add the bottom.

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davec69
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Post by davec69 »

Anyone with ideas on getting more more bottom from this build?
davec69 wrote:I just finished this build using the McElroy layout, above. I went with the 2N3819@4.6v / LM386 version, everything else is the same as on the layout.

I seem to be having the opposite problem of some of the earlier posts. My build sounds great. Gain-wise, its perfect, but, it's a little too bright. When I turn the tone pot fully counter-clockwise, I'm just about to hit the sweet spot when I reach the end of the pot travel. As I bring up the tone pot, it just gets brighter.

What adjustments can I make to add more low end to round out the sound?

An example would be if you had a stereo, with only a treble knob, and no bass knob. No matter how much you raise or lower the treble knob, I doesn't put in the missing bottom. I need to somehow add the bottom.

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roseblood11
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Post by roseblood11 »

A mod for more bass is explained somewhere at the beginning of this thread. I used a three-position switch for different cap values. But even with the stock value, there´s quite a lot of bass. I guess you made a mistale somewhere.

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Renegadrian
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Post by Renegadrian »

I just built the circuit, took mcelroy's vero and shrinked it. it works very well and it's one of my fav circuits ever.
it has a good amount of gain, still is so silent. didn't put the 47µ to filter the voltage (and omit the diode too) but it works so fine on battery. I'd put a filter cap only with the wall wart, then I'd put it on the power jack as I always do. The circuit has a really useful TONE control, and I like its sound on every position! I have to say that the 386 choice is critical, I found the best result with a JRC386D, tried a LM-1 and a LM-4, they are good but also a little fizziness on sustain. so JRC stays. get some different types if you intend to build it too!!!
tranny is the regular 3819.

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Post by Cannibal »

I've bdrawn a perf layout for the titan. I have made two mods to it: a switch for normal/more bass as described earlier in the thread and a switch from the standard input jfet booster to a jfet mu-amp. The layout is not verified, and i'm not sure that the Mu-amp stage is really necessary. However, here it is:
sonic tyrant.gif
Seiche wrote:there's a difference between being drugged (I don't think it was only booze) and retarded.

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Post by gilmour_pugliese »

ShortScaleMike wrote:Thanks for the corrections marauder, with these changes the vero is now verified.

Image
Hi guys! I've built the ST with this layout (thanks Mike!) and I've used these mods:
-C3 from 4.7n to 10n (more bassy response... I'll try 22n or 33n)
-100kA pot for Volume instead of 10k

Now the pedal is perfect for me (no boost effect when you turn the Tone pot) but I wanna know if I must lower the value of C6 from 10uF to 0.1/0.22uF. In fact here (referred to Boss SD1):
viewtopic.php?f=10&t=12582

I've read:
JakeAC5253 wrote:6. It looks like the schematic shows a 10k pot for the volume, would it be alright to use a 100k instead? Why or why not?
A 100k volume pot will work fine, and you can then reduce the value of C7 (OUT cap) to 0.1 or 0.22.[/quote]

Now the pedal sounds really good, but it picks some radio interferences at high gain settings... I've solved placing a 100pF cap between Drain and Gate of the FET (I've used the BF244)... It's a right solution?

thanks to all :thumbsup
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gilmour_pugliese
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Post by gilmour_pugliese »

UP... :horsey:

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kinski
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Post by kinski »

are the pots linear or audio? thanks!

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Cesfa
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Post by Cesfa »

i create this great pedal but i have a little problem.
This is the link of semple: <img src=http://www.filedropper.com/download_button.png width=127 height=145 border=0/>
At the 30 second you can hear buzz when you hold a long note.
What is the problem?

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Cesfa
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Post by Cesfa »

sorry for link: yhis is the right.

http://www.filedropper.com/problematitan

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kinski
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Post by kinski »

Just built this last night using McElroy0717's layout. All stock, except the 100kA Volume pot. This thing sounds great! I will say, the tone control is not that effective, but gets the job done I guess.

Thanks to everybody who worked on this, and McElroy0717 for the layout!

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Post by kinski »

Okay, so I am also getting some unnatural decay with my build. I tried a few different chips and adjusting the trimmer, and nothing improved it. Its subtle, but now that I hear it, its really annoying me. Its a shame, because if this issue was not happening, it would be my favorite dist/OD at the moment.

I know a bunch of others here have had this problem. Has anyone found any solutions?

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Post by stevo83 »

Had the same problem mate. Spluttery Decay.

Think it might be something to do with the Transistor stage slamming the input of the LM386 chip to hard or something. Who knows. :scratch:

I built a Big B*stard instead. Search for the thread on DIY Stompboxes and you should find it.

The circuit sounds similar and did not splutter for me.

Alternatively you could buy a bunch of different LM386 chips and go through them to see if some do not splutter.

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kinski
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Post by kinski »

I'll look more into the Big B*astard.

However, I'd love to get the Sonic Titan to work better. I LOVE everything about this circuit, except that annoying decay. With chords on lower gain setting, the distortion fades very unnaturally, and if let you certain single notes sustain, the distortion will just cut off abruptly, leaving just a clean tone. Its quite strange. Other than that...it sounds fantastic.

Anyone have any ideas? Different JFET, perhaps? I tried a JRC 386 and found no difference. :scratch:

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Post by gilmour_pugliese »

I've built 3 ST with no problems... My ICs are LM386 and the FETs are BF244A and the pedals have a good decay! Have you set the trimpot at approx. 4,5/5vdc?

Little OT: someone has picked radio interferences with the gain maxed? I've solved with a 100p cap between D and G of the FET... It's a good solution? :horsey:

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Post by kinski »

Hmm...maybe I'll try the BF244A, but I'll have to track them down first.

I've been biasing by ear. I've set the trimpot for min and max gain, and everything in between, and they all sputter. The trimpots highest gain is midway. Anything before or after midway is a reduction in gain. Its supposed to be like that, right?

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Post by kinski »

Radioshack is the only local non-internet place I could find a JFET. They only seem to carry the MPF102. Is this worth a try? I don't know much about specs of JFETs.

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Post by kinski »

Well, as I guessed, the MPF102 did not work. There was sound, but it was muffled and barely distorted. I'll have to wait till my next parts order to get some other FETs to try. Any other ideas to help the decay issue? Nobody had a bad decay in there build and then fixed it?

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Post by kinski »

Okay, I just realized, the decay on this circuit is PERFECT if I use DC power. Nice! I just seems to hate battery power, and its a pretty fresh one too. Thats fine with me, as I always gig using DC power. I just use batteries around my apartment if I'm to lazy to set up the pedal power. Glad to have found a solution!

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Post by stevo83 »

Glad you found a solution mate!

Out of curiosity; what 386 chip and jfet are you using?

Did you alter any components or add any other mods in comparison to the original schematic?

Would like to get mine working without the horrible decay as it is a cool sound circuit for sure!

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