Lectric Dandy Horse - dark sound SOLVED

[magicman]

Greetings, I have a Lectric Dandy Horse I have been trying to tune and I get significant treble roll off when the effect is on. The chorus flanger and echo sounds are still great, but it sounds like someone threw a blanket over my amp when it's on. I have a 2005 reissue Polychorus (different circuit-I know) and it sounds signifigantly brighter of a chorus sound. I just wanted to verify if this is how the original unit is supposed to sound.

Thanks everyone in advance.

 

[DGWVI]

It's a more neutral circuit- shouldn't be too bright or dark. It's possible you put a higher value cap somewhere in one of the filters

Got some pics of your build?

 

[magicman]

It's a more neutral circuit- shouldn't be too bright or dark. It's possible you put a higher value cap somewhere in one of the filters

Got some pics of your build?

Thanks for the reply! That's what I have read about it, that it is very neutral sounding, it really surprised me how dark it was. I was meiticulous, but there are so many caps in this thing...its possible I made a mistake, maybe got I a multiplier wrong somewhere in the filter.

That's where my brain went, I will get some photos and a sound sample up here a little later.

 

[juice886]

Input impedance in this circuit is less than 100k. That can cause some audible loss of high frequencies if you are using 'true bypass' all the way. Try to connect some pedal with an active buffer before your Dandy Horse in your signal chain and check if that helps.

 

[magicman]

Input impedance in this circuit is less than 100k. That can cause some audible loss of high frequencies if you are using 'true bypass' all the way. Try to connect some pedal with an active buffer before your Dandy Horse in your signal chain and check if that helps.

Thanks! That is a good thought too, I have tested it a bunch by itself. Right now it is in the middle of my chain, which is mostly true bypass but has a Boss TU-2 towards the front.

I am familiar with the issue with my Boss CE-1 clone, which is true bypass and has a drastic roll of of treble when it is used by itself. That is also on my board, about 5 or 6 pedals after the Dandy and it does not experience the treble loss with the Boss TU-2 in front of it. Even 15 or so pedals away and the buffer still works.

I will give it a shot though! Maybe it just doesn't like being in this spot in the chain or by itself...

 

[juice886]

Okay, then that is not what is causing an issue in this case.

 

[eh là bas ma]

I tried my Dandy Horse build with various instruments, like synthetizers, guitars, bass, and never noticed any treble loss, even by itself.

 

[magicman]

Okay, then that is not what is causing an issue in this case.

I'll play around with some placement, I'm not totally ruling out that it isn't influencing it as I did opt for the true bypass scheme. Thanks for the idea!

 

[magicman]

I tried my Dandy Horse build with various instruments, like synthetizers, guitars, bass, and never noticed any treble loss, even by itself.

Thanks for the feedback, I appreciate it. It is very helpful to hear how other people's units sound. There is a noticeable treble roll of on mine with any instrument. I've mostly been playing it with guitar.

 

[eh là bas ma]

it's a very long shot but i'd suggest to carefully check all capacitors values, maybe you misread a value on a part somewhere.

Could easily also be a bad soldering joint that looks perfect.

In that case, i guess you'll need to audioprobe the signal path and see where the treble loss happens.

 

[magicman]

it's a very long shot but i'd suggest to carefully check all capacitors values, maybe you misread a value on a part somewhere.

Could easily also be a bad soldering joint that looks perfect.

In that case, i guess you'll need to audioprobe the signal path and see where the treble loss happens.

Thanks for the reply. I just check all of my cap values, they are all correct. Busting out the audio probe next.

 

[magicman]

Gutshot

 

[magicman]

UPDATE SOLVED. I installed the incorrect resistor in position R39. This took me a while to find the time to fix, but I finally got around to it this time..

My next move was to go through and check every component. I checked every capatior, and they were all correct. Next I moved onto the resistors, by value. 100k was all correct, and then I got to 100r and discovered this maroon 100k resistor I installed by mistake! Only 1000 times what it was supposed to be...

What I think happened is I was out of stock of 100r, checked my partner's parts bin and found this in a drawer labeled 100r. I had been checking values 4 times before I commited to solder for the rest of the build but it is possible I slipped up in a rush to hear it....Many, many componenets in this build.

Once the offending resistor was replaced, the dullness went away, it now has a beautiful glassy top end like it should. The Level tim pot, which I previously had cranked all the way, had to be turned down quite a bit as it was now giving it a huge boost.


I am still having a bit of difficulty tuning the gain 2 trim pot, but I think I am at a happy medium between the modes at the moment. I might replace it with a multi-turn trimmer in the future, and am going to continue to double check my components to make sure I did not make any other mistakes.

Thank you all for the help and for the ideas. Anyone building one of these, don't be too discouraged if you have issues. Just slow down, take your time and check everything at least 4 times before soldering! I have built dozens of pedals, and many BBD circuits before this one and still had a few boofs along the way.