Monday, 24 June 2013

EHX Bassballs

Little something more for the bassists.. Should work nicely on guitar too.



61 comments:

  1. Spent ages trying to get the "topopiccione" vero layout working to no avail, so hoping this gets verified. Once it is I'll probably add a blend pot (5k) where the two 2.7k are, make the trims external, and add a decay switch fast/slow on the 330k (can't remember the value, lower is faster decay anyway, maybe 50k-100k?

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    1. This is from Topopiccione schematic... Haven't read about possible mods, so i couldn't say for sure at the moment.
      +m

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  2. Overall volume and distortion only would be cool additions as well. I had this and I remember it being crazy loud...

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    1. Install an easy volume pot :) Take the output to 100K log pot's lug 3, lug 1 to ground and lug is the new output. I would also snip the 47K resistor from the input.
      +m

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    2. Which resistor are you referring to? I'm not seeing one directly off the input.

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    3. My bad.. From the output, of course.
      +m

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  3. I assume both ICs are the same? Only IC1 is listed in the footnotes.

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    1. I'll fix the notes once i'm back home. I assume they are the same dual opamp. Schematic doesn't have any info on them.
      +m

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    2. The Topopiccione schematic says that the IC1 is a 1458 and IC2 is a 4558.

      I know various folks have had issues building these over the years, so I'd love to hear if someone successfully builds this one.

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    3. Nope. Schematic doesn't say that.
      http://topopiccione.atspace.com/pjimages/EHBassBalls.sch.gif
      BOM on the other hand does.
      http://topopiccione.atspace.com/pjimages/EHBassBalls.lst.txt
      And yes. I think that makes sense.

      Fixing the labels right now.. Fixed.
      +m

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    4. Yes, I meant the BOM for the project at Topopiccione... sorry for the misnomer.

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    5. Yes, in all this kind of envelope filters, the 1458 as IC1 seems mandatory (Dr Q, Meatbal, and so on).

      BR

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    6. No problem. Thanks, actually. I rarely look for the BOM, like in this case. Made an assumption that wasn't exactly correct. Both are dual chips..
      +m

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  4. Forgive my being a pedant, but you've labelled IC1 as 1548 not 1458!

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    1. Fixed it slightly too fast. :) Fixed.
      +m

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  5. Damn you! I just did this on perfboard.

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  6. Hey all! Long time lurker, first time caller here:

    I'm curious as to what metal (copper?) wire y'all are using for the jumping between rows on the vero board. Could someone please share a link with me to the product on the tayda or mammoth electronic sites? I have found plastic wrapped wire on those sites, but it looks like bare metal being used for the jumpers in between rows here.

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    1. I personally use 0R resistors for open links that span over more than one row. For smaller ones and the ones under ICs i just use leg trimmings from caps.
      +m

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    2. Since my 'proper' wire from the electrical component store ran out I've been using wire I had left over from wiring some lights at my house. It's the white 3 core stuff (black, red, yellow/green) stuff that has multiple solid strands inside. It works fine and is cheap.

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  7. Just use the leads from your trimmed components or the wire you use for pots.

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  8. Oh, tag it now!!!! Sounds great, both in clean and dist modes. Trims are very sensitive and you can get lots of tones.

    Real good envelope filter, one more fot the collection. Hope to add the Mutron Micro V soon :P

    BR

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    1. BY the way: MC1458 works great. LM1458 should work too, will try later a NE5532, but MC uses to be my choice in this kind of effect.

      BR

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    2. Thanks man! I'll tag it right away!
      +m

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    3. And boxed :)

      Guts:

      https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-prn1/1010901_10200625946083622_1369985052_n.jpg

      Front:

      https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-prn2/968779_502339366504583_2042185024_n.jpg

      BR

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    4. Javicap

      Just tuning the trims by ear or aiming for a certain voltage?

      Thanks

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    5. Just by ear. I'll use this effect with humbucker's guitar mainly, so better trust your ear than a fixed voltage :) Take the trims to the middle point and from here, just listen and tweak.

      BR

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    6. Cool. Thanks. Nice build pics btw...

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  10. 2 issues:

    1. No fuzz
    2. Response control does nothing

    Voltages: ( no input)
    1458
    1. 4.6
    2. 4.6
    3. 4.58
    4. 0
    5. 0
    6. 7.5
    7. 8.4
    8. 9.07

    4558
    1. 4.58
    2. 4.58
    3. 4.58
    4. 0
    5. 4.58
    6. 4.58
    7. 4.58
    8. 9.08

    Q1
    C 9.08
    B 7.95
    E 7.3

    Any suggestions?

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    1. If you have 0 volts on the 1458 pin 5, I think that's clear where's the problem.

      BR

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    2. Forget about it, it has to be grounded too. Do you have the other transistor's voltages? BR

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    3. Well, after taking a deeper look at the schematics:

      If you get sound but no fuzz, and the pot doesn't work, you have to check the components from pot lug 2 to the diode (4,7 k resistor, 470nf cap, 2,2m resistor to ground, 220k resistor, bridge from IC 1 Pinn 7 to the diode.

      It seems that you signal is going for just one way, instead of two that join on the diode, and when you use the switch, you cut that way (as intended) but havin a problem in the other way, you'll always get a cleanish sound and the pot won't do anything.

      Hope it helps

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  11. Thanks for the help!

    Here they are:

    Q2
    C 0
    B 0.64
    E 0

    Q3
    C 0
    B 0.64
    E 0


    The filters both seems to be working, as the tone changes dramatically when they are adjusted.

    Just no sound in the fuzz position and the Response pot doesn't seem to be doing anything in the clean position.

    I've measured all the resistors and caps between SW1 and Sw3 and input. All correct values and good solder connections.

    I have not checked from SW 2 onwards as it seems with no output from the fuzz, the problem should be before Sw2.

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    1. Can't find the fault, ordered 2 more opamps, this time LM358s and going to start a new vero.

      Was probably going to build 2 anyway.

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    2. After checking everything over again (and again) I can't find any faults in component values or connections.

      So I swapped out the 1458 with a 5532 and the sweeping came alive!

      I even got some output from the fuzz if I cranked the response and strummed hard. Not really usable with the 5532, but I think it tells me the 1458 is the problem!!!

      I then popped in a TL072 and no sweeping and no fuzz, so now I'm not sure if the 1458 is bad since the symptoms are the same with the TL072.

      Does this make any sense?

      I do have a couple of LM358s on order so I'll probably answer my own question in a week or so when they show up.

      Very frustrating

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    3. Hi Mike,

      Yes, the 1458 may be the problem, as let's say, in this kind of effect (filters) is mandatory.

      In this one and the Doctor Q I used MC1458s and where the ones that made these effects come to life. The LM1458 should work fine too, so I bet yours is defective.

      Luckily, MC1458-LM1458 is pretty cheap, so, my advice is that you get a 50 pieces lot and forget about to problems related to this IC

      http://www.ebay.es/itm/50PCS-LM1458N-IC-OP-AMP-DUAL-8-DIP-NEW-GOOD-QUALITY-D6-/300917434272?pt=LH_DefaultDomain_0&hash=item461013a7a0

      BR

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  13. Looks like a discrepancy between the schematic and the layout.

    C12 & C13 are both 4n7 on the Topopiccione schematic and BOM.

    http://topopiccione.atspace.com/pjimages/EHBassBalls.sch.gif
    http://topopiccione.atspace.com/pjimages/EHBassBalls.lst.txt

    The vero layout has them as 47n. They are pictured just above the right 10k trimmer.

    Which is correct?

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    1. You would need to ask Topopiccione guys, but as Javi built this succesfully, i believe the schematic is correct.

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    2. Yes, they should be 4n7, the vero layout here has them as 47n.

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    3. what would be the difference in sound? I have already installed 47n

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    4. I'm having the same problem as Mike Oriente had - no response control with the pot, and one switch position (top row on) no sound. I've also been over all the components several times but no dice. Tried swapping ICs, too. I also swapped the 47n caps for 4n7, and they made no audible difference. If anyone has a lead on this info would be much appreciated. Mike - any word on how you got it working?

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  14. You can count me in as a second verification of this. I built this for a friend who liked his Bassballs, but wanted the distortion footswitchable and the trims mounted as external pots. Works great!

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  15. Anyone else build this end up with footswitch pop that won't go away by any of the standard methods? I even switched over to a DPDT with millenium bypass to see if the footswitch itself was the issue. On millenium bypass, the LED stays lit, so either I've messed something else up (possible, but I've built this bypass a number of times before) or it's pointing to a peculiarity with the circuit that might also be causing a pop on switch-over.

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    1. False alarm. I connected my output two rows too high, thus skipping the output cap and sending 4.5v dc straight up my output along with the signal. It's always the stupid mistakes that get you...

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  16. would it be possible to mount the volume pot only for the overdrive signal?

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  17. Just to be clear, since you've only mentioned the numbers. Would an LM1458, and an NJM4558 be correct for the ICs?

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  18. a 1458 is a 1458. same with a 4558. differences are pretty marginal.

    i've built a few of these now, i call 'em corpulent cojones. a couple "tricks" as it were.
    if it seems like it doesn't work at first, try turning the range of the filters down some... this seems to apply to alot of these kind of pedals.

    also, tune the filters however you like, but not to the same sweep... i like one up high and one down lower.

    these work KILLER with guitars. i like 1n34 or 1n60 diode clippers after the output cap, but hey, i'm a weirdo. ;)

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  19. Hey, I know this may seem like a silly question, but I was wondering what exactly the pots are that I am supposed to use in this? Can anyone link me to a sight where I could acquire them?

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    1. looks like there is just one. A 10k linear. Any electronics shop. http://www.taydaelectronics.com/10k-ohm-linear-taper-potentiometer-with-solder-lugs.html

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  21. I built a version with a footswitch for distortion, mounted the trimmers externally and added a volume control as well, it is amazing!
    Here's a pic
    https://plus.google.com/photos/108669795125442168197/albums/6108625318465963473/6108625322965172610?pid=6108625322965172610&oid=108669795125442168197

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    1. Would someone clarify the link/cuts for me. When a link goes across a cut, does the link stop there and then continue after.
      Thank you

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    2. No the link always goes from the top to the bottom of the line shown, unless you see a blue dot in it, then it daisy chains at that point.

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    3. Hi Lennart H, how did you wire the Distortion switch with led? Thanks

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  22. I just finished my build, it turned out nice. i still have a little tweaking to do, would someone help me out with what exactly the trimmer pots control. I tweaked them by ear and thought I liked the sound but after I put it together, I'm not so sure I like it. If I knew what they control, I think that would help.
    Thank You

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  23. I built a second one but having trouble with it... Q1 always keeps heating up, I replaced it but the new one does the same. (and I'm getting sound but no effect if i plug in my bass)
    the voltages are
    Q1:
    C: 9.0
    B:1,52
    E: 0

    I just checked those again and the transistor suddenly stopped heating up. the effect actually worked for about a minute. but after replugging the power supply the issue was back. sounds like a loose connection or something but how could I figure out where or what to search for exactly?

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  24. im just getting a constant drone that changes pitch as i adjust the trim pots. No signal, only when bypassed. :'(

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  25. Up and running, thanks for the info!!

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