So I built the bassballs with the topopiccione layout.
Typical story. No Sweep.
I have two LM1458N 's or so they are called from tayda.
Was going to measure voltages and saw immediately that both Pin1 and Pin8 have 8.9V on it.
These aren't remotely connected on the board Checked for solder bridges yadda yadda.
Swapped with my other LM1458N same issue. So I pulled them and attached an clip to pin8 and ground to pin4 as is typical with Dual OPamps
And pin 1 still measures 8.9 volts I'm pretty sure that isn't supposed to happen. I assume my 1458s are fakes or blown?
If thats the case then I will be kind of happy since I built a DR a few months ago with the same problem.
EDIT: I may be mistaken My 4558s all measure the same when connected with flying leads.
Ill just put up another post with the DEBUG thread info when I get done with the overnight maintenance at work.
Did you do larrys layout?
I still have mine in the experiment box so if needs be I could check my voltages for you.
Here's the thread
http://www.diystompboxes.com/smfforum/index.php?topic=101858.0.l
Just so you know I got my chips from Tayda IIRC
1.What does it do, not do, and sound like?
Passes sound in bypass.
Engaged: mildly effected sound that changes sweep when the trimpots are adjusted.
Sensitivity pot has seemingly no effect on sound.
When the FUZZ switch is engaged I get NO Sound
2.Name of the circuit =
EHX Bass Balls
3.Source of the circuit (URL of schematic or project) =
http://topopiccione.atspace.com/pjimages/EHBassBalls.sch.gif
4.Any modifications to the circuit?
None
5.Any parts substitutions?
N/A
6.Positive ground to negative ground conversion?
Negative Ground
7.Voltage Source Reading? =>
8.95V
Voltage at the circuit board end of the red battery lead =
8.94V
Voltage at the circuit board end of the black battery lead =
0v
Now, using the original schematic as a reference for which part is which (that is, which transistor is Q1, Q2, etc. and which IC is IC1, IC2, C1, and so on) measure and list the voltage on each pin of every transistor and IC. Just keep the black lead on ground, and touch the pointed end of the red probe to each one in turn. Report the voltages as follows:
IC1 (or U1) = LM1458N
P1 = 8.28V
P2 = 7.38V
P3 = 0V
P4 = 0V
P5 = 4.40V
P6 = 4.51V
P7 = 4.51V
P8 = 8.94V
IC1 = 4558
P1 = 4.48V
P2 = 4.48V
P3 = 4.47V
P4 = 0V
P5 = 4.47V
P6 = 4.48V
P7 = 4.44V
P8 = 8.94V
Q1
C = 8.94V
B = 7.83V
E = 7.19
Q2
C= 0V
B= 0.63V
E= 0V
Q3
C= 0V
B= 0.64V
E= 0V
D1
A (anode, the non-band end) = 8.28V
K (cathode, the banded end) = 7.84V
Definitely something wrong around U1! That output (P1) should be nowhere near V+. The link to the schematic doesn't work...can you post it from Photobucket or something? I'm wondering what your VRef voltages are (assuming that you have a bias coming from somewhere). Probably way off.
Can you audio probe this bugger? That may tell you pretty closely where the real trouble is happening. Can't do much more than this with no schema, and didn't find it on my own in the 2 minutes I just searched for it...
You can dispel any concerns about the chips being "fakes". I've bought and used them before, with full success.
You know, there is a reason why criminals don't go around counterfeiting pennies.
+1
I've bought a fair few of those LM1458 from Tayda, and they've all worked well - They sound particularly good in a Timmy.
try some different opamps. it doesn't HAVE to be 1458's in there, they are used cuz they can hit the power rails.
i've had the same damn problem with several attempts at this... i ended up giving up on it.
that said, i've used tayda 1458's, and they work great. BUT they seem to blow up pretty easy if there's an issue with a circuit...
You're half right. Three of the 4opamps can be anything but the 4th the one used for the envelope follower does need to be a 1458 to get proper sweep, and the classic Bass Balls "fuzz".
the classic fuzz is TERRIBLE. :icon_mrgreen:
i was obtuse... i shoulda said to see if it was workin', my bad!!
I've built that one with no issues, so I can confirm the layout, did you check all the usual suspects, solder joints that should and should not be touching?
Quote from: pinkjimiphoton on September 20, 2013, 09:34:09 PM
the classic fuzz is TERRIBLE. :icon_mrgreen:
i was obtuse... i shoulda said to see if it was workin', my bad!!
Oh believe me Sir James, I am definitely on that page with you, but some folks like it, and if they like it they should know what it takes to get it.
:icon_mrgreen:
<shudder>
your mod to it is a huge improvement, mark, but still it's like... ya know... just cuz ya CAN do something, doesn't mean ya always should!!
;)
makes me think of the "deluxe" big muff.... what a piece of poo. now they're going for 200+ broken. <shakes head>
When the word "vintage" gets mentioned, sometimes there is no accounting for taste.
hey mark, my name is jimi, and i'm a fuzzaholic... ;)
Quote from: GibsonGM on September 20, 2013, 08:08:34 AM
Definitely something wrong around U1! That output (P1) should be nowhere near V+. The link to the schematic doesn't work...can you post it from Photobucket or something? I'm wondering what your VRef voltages are (assuming that you have a bias coming from somewhere). Probably way off.
Can you audio probe this bugger? That may tell you pretty closely where the real trouble is happening. Can't do much more than this with no schema, and didn't find it on my own in the 2 minutes I just searched for it...
I dont think it's a solder bridge because pulling the IC from the Socket Pin 1 reads 0V
I wouldn't even know where to begin to probe.
I suppose the output for the envelope follower? since with the switch engaged I lose all sound so it stands to reason that its not outputting?
Edit:
I'm getting No output on pin 1 of the 1458, I am getting signal on pin 2.
i used a 358 in my breaded attempt....worked ok IIRC..
take the schematic, and work your way thru with the audio probe from the input of the circuit thru to each node. when suddenly it goes away, that's your problem.
did you use any standing components? if so, please re-flow the board in those areas...i find standing resistors sometimes move if soldering adjacent components and they lose some of their connection ability.
reflowing them while making sure there's a good physical connection sometimes fixes things when everything else fails. you may never know where the problem was if you reflow the whole board, but if it ends up working, who cares?
hang in there, you WILL get it!!
Quote from: pinkjimiphoton on September 22, 2013, 08:40:24 PM
take the schematic, and work your way thru with the audio probe from the input of the circuit thru to each node. when suddenly it goes away, that's your problem.
did you use any standing components? if so, please re-flow the board in those areas...i find standing resistors sometimes move if soldering adjacent components and they lose some of their connection ability.
reflowing them while making sure there's a good physical connection sometimes fixes things when everything else fails. you may never know where the problem was if you reflow the whole board, but if it ends up working, who cares?
hang in there, you WILL get it!!
I probed a bit, Shouldn't I have output on Pin 1 of the 1458? Thats where it connects to the 4148.
I have signal on Pin 2 and subsequently the 220K that goes from pin 2 to pin 1, but there is no signal on pin1/opposite side of 220k.
Thats where the fuzz line connects to the filter section so Im fairly certain I have to have Signal there. I can't figure out why I do not. Its not pulled to ground because I can read dc voltage on it.
I had the genius idea to connect a test probe lead from a broke Multimeter and soldered it to my test box (DPDT switch for bypass with I/O jacks and cut in half aligator clips for board in and board out 9v and gnd. I soldered the probe to the lug of the output alligator clip. So with the output aligator clip disconnected I can probe around with everything plugged in nice an neat.
Quote from: deadastronaut on September 22, 2013, 05:26:16 PM
i used a 358 in my breaded attempt....worked ok IIRC..
Yeah, they'll work, but the sweep on 1458s is better for some reason.
Bumpiddy bump bump bumpiddy bump bump
The first check that one always has to do is verify that there is an AC voltage going into the rectifier op-amp (the pin where R5 and C3 meet) when you strum, and a DC voltage being produced by it at the junction of D1 and R6. You should see something around 50-60mv for the first (depending on pickups), and between 1 and 3V or so for the second.
If you get a thumbs up on the furnishing of a control signal by the rectifier/follower portion of the circuit, then the next thing to do is verify that the filters work. Set the switch to the non-fuzz setting, set the sensitivity to nil, and play with the trimpots to verify that each of the filters respond appropriately.
If the envelope follower portion responds properly, and the filters behave as expected, then that point to one or more of the transistors as possibly being either dead (not likely) or having the wrong pinouts (more likely).
That isd the general strategy to pursue when troubleshooting anything with a sidechain: separate it into the part that detects signal, the part that gets controlled by the sidechain, and the path that directs the control signal to the portion being controlled. Failure in any one segment means no effect, but you need to narow it down to what segment.
Quote from: Mark Hammer on September 23, 2013, 12:20:40 PM
The first check that one always has to do is verify that there is an AC voltage going into the rectifier op-amp (the pin where R5 and C3 meet) when you strum, and a DC voltage being produced by it at the junction of D1 and R6. You should see something around 50-60mv for the first (depending on pickups), and between 1 and 3V or so for the second.
If you get a thumbs up on the furnishing of a control signal by the rectifier/follower portion of the circuit, then the next thing to do is verify that the filters work. Set the switch to the non-fuzz setting, set the sensitivity to nil, and play with the trimpots to verify that each of the filters respond appropriately.
If the envelope follower portion responds properly, and the filters behave as expected, then that point to one or more of the transistors as possibly being either dead (not likely) or having the wrong pinouts (more likely).
That isd the general strategy to pursue when troubleshooting anything with a sidechain: separate it into the part that detects signal, the part that gets controlled by the sidechain, and the path that directs the control signal to the portion being controlled. Failure in any one segment means no effect, but you need to narow it down to what segment.
I am getting AC signal that spikes when strumming at the junctiong of C3 and R5- granted its around 100mV but it "idles" at 50ish mV which could just be my crappy DMM.
I am getting 7 volts DC at the junction of R6 and D1.
This goes back to me getting over 8Vs on pin1 of the 1458 I stated earlier. THere is no solder bridge because pulling the 1458 and measuring the pin sockets reads 0V
Assume a bad 1458?
Appears I have bad luck all 4 of my 1458s from tayda are bad. reading the same 8v on pin one
Tried a 5532 and Im getting sweep now so thats great. the distortion is ridiculously gated. though when enabled.
Mark is that a function of a 5532 or is there something else to look at?
Here is a sound cloud clip. I recorded through the iPhone jam up app since I don't have my recording equipment at the house.
https://soundcloud.com/nicholas-schaffrin/bass-balls-test
Quote from: Mark Hammer on September 20, 2013, 08:52:47 AM
You can dispel any concerns about the chips being "fakes". I've bought and used them before, with full success.
You know, there is a reason why criminals don't go around counterfeiting pennies.
4x tayda 1458s do not envelope in a meatball build of mine... go figure!
Quote from: LaceSensor on September 28, 2013, 03:04:53 PM
Quote from: Mark Hammer on September 20, 2013, 08:52:47 AM
You can dispel any concerns about the chips being "fakes". I've bought and used them before, with full success.
You know, there is a reason why criminals don't go around counterfeiting pennies.
4x tayda 1458s do not envelope in a meatball build of mine... go figure!
Did you have the LM1458Ns too? They also have LM1458 or the HA17458? Mine were the N ones
1458 is a 1458
Is kinda like tl072p or cp or whatever.
The codes are relating to characteristics that don't matter to pedal builds.
Quote from: LaceSensor on September 29, 2013, 04:58:32 AM
1458 is a 1458
Is kinda like tl072p or cp or whatever.
The codes are relating to characteristics that don't matter to pedal builds.
Not if the 1458Ns are from a different manufacturer and/or factory seconds.
Not saying that's the case here. Im just curious if the 1458Ns have worked for people from tayda
Bump
Thanks to the info from Mark I saw that I was not getting any change in DC voltage after D1. Since I was out of 1458's I tried the 5532 as per the above post.
I now get sweep that sounds alright. Already ordered 4 more 1458's from tayda (fingers crossed that they work)
The Fuzz is kind of gated though. I'm a very heavy handed bassist (grew up playing rush tunes) and I have to really push myself to get my jazz bass to get any "reasonable fuzz"
Here is a soundcloud clip with guitar. Which actually works the fuzz better than my Jazz Bass does.
https://soundcloud.com/nicholas-schaffrin/bass-balls-test
Mark H. the 5532 shouldn't be the cause of the lack of fuzz should it?
In fact, the "fuzz" in the Bassballs is just the sound a 1458 makes when pushed a little too hard. Since it HAS to be pushed in order to get enough gain for the envelope follower, it was a freebie just waiting to be exploited, so that's what EHX did.
Quote from: Mark Hammer on September 30, 2013, 07:29:38 PM
In fact, the "fuzz" in the Bassballs is just the sound a 1458 makes when pushed a little too hard. Since it HAS to be pushed in order to get enough gain for the envelope follower, it was a freebie just waiting to be exploited, so that's what EHX did.
But what about the gating I'm experiencing?
That I can't help you with.
Quote from: Mark Hammer on September 30, 2013, 09:06:19 PM
That I can't help you with.
Ahh righto
Thanks for the help thus far.
I'll see what happens when the new 1458s come in
Bought 4 more 1458N s from tayda. They are also bad. Switching between the 5532 continues to sweep so I can firmly say stay away from the 1458n from tayda. Haven't tried their 1458 non-N yet but the N ones appear to be duds. I bought the original ones over a year ago and these ones last week