Author Topic: Current Lover 2015 Clock Range Frequencies  (Read 255 times)

Mcentee2

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Current Lover 2015 Clock Range Frequencies
« on: May 30, 2018, 08:42:13 AM »
Hi all,

I have a new Madbean Current Lover 2015 and the sweep didn't sound very "sweepy", so have got my multimeter out that is capable of frequency measurement and have the following at the *lowest* point of the Clock trim, ms times are worked out using "ms=stages/(freq in khz * 2)"

High: 620 khz = 0.82ms
Low:  170 khz = 3.01ms

These numbers go through the LM 311 Pin 7 and into the MN3007 Pins 2 and 6, and the low side freq of 170 khz seems a bit high, leading to a very narrow sweep of 0.82 - 3.01 ms.

With Filter matrix on I get even worse on the low end, but I know that the circuit LFO and "Filter/Matrix" are different :)

Range Fully CCW: 600 khz = 0.85 ms
Range Fully CW:   266 khz = 1.92 ms

I was expecting something more .8ms  - 7ms or so, freqs 70khz - 600khz for a MN3007 1024 stage bbd

I also have a Boss HF-2 as well and that seems to operate "by the book", with sweeps from 40 - 500 khz so I know my multimeter is ok.

Voltages measured today with a 9.2v Battery, pdf figure is first, my figure is second. I have put a * next to the ones I think are "dodgy":

IC1   4558   
1   4.59   4.46
2   4.59   4.47
3   4.18   4.05
4   0   0
5   4.51   4.38
6   4.55   0
7   4.53   4.42
8   9.13   8.87

IC2   MN3007   
1   9.13          8.86
2   ~4.45   4.27
3   ~4.85   4.75
4   41mV   380mv *********
5   0   
6   ~4.45   4.37
7   ~4.2          4.87
8   ~4.2          4.9

IC3   CD4049   
1   9   8.8
2   4.5   4.38
3   4.5   4.38
4   4.5   4.38
5   4.53   4.38
6   4.5   4.35
7   4.5   4.36
8   0   0
9   4.5   4.36
10   4.5   4.36
11   4.5   4.36
12   4.5   4.36
13   ignore   
14   4.5   4.28
15   4.5   4.33
16   ignore   

IC4   CD4013   
1   4.53        4.34
2   4.53        4.34
3   varies   4.7-5.3
4   0   
5   4.5        4.35
6   0   
7   0   
8   0   
9   0   
10   0   
11   0   
12   9        0  ****** are these two a typo ?
13   0        8.75  ***** are these two a typo ?
14   9        8.75

IC5   LM324   
1   varies   7.46
2   ~4.2   4.07
3   varies   4
4   9   8.69
5   0   
6   0   
7   7.8           0   **********   Looks very odd!
8   varies   2
9   varies   2
10   varies   2
11   0   
12   ~4.2       3.9
13   ~4.2           3.9
14   varies   4

IC6   LM311   
1   0   0
2   varies   
3   varies   
4   0   0
5   9.14   8.69
6   9.14   8.69
7   varies   
8   9.14   8.69

IC7   4558   
1   4.55   4.36
2   4.55   4.36
3   4.55   4.36
4   0   
5   4.51   4.3
6   4.55   4.3
7   4.55   4.3
8   9.14   8.67


I have checked some components around those areas but all seem ok, I will continue to check values, but any guidance would be appreciated.

Thankyou

Mcentee2

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Re: Current Lover 2015 Clock Range Frequencies
« Reply #1 on: May 31, 2018, 04:53:08 AM »
Solved :)

Another symptom of what turned out to be the problem was the Control Voltage coming off Pin 2 of the LM311 only varied between 1.0v - 2.2v (9v supply) or 1.3v - 3.1v on a 12v supply), giving very little sweep.

After reading various threads on the EM3207 etc on DIYSB forum from the brilliants guys there, I tracked it down to the builder using a 10k Lin pot for the Range control instead of a 100k Lin pot !!!!

Swapped it out now, and the LM311 Pin 2 CV now reads 1.1v - 8.8v  (on a 12v supply) during flanger sweep (not static matrix mode)

After Clock trim adjustment I can get the lowest 4013 Pin 1 clock rate at 70khz on the knuckle , high is about 1000 khz (yes 1 Mhz!!)* with no chirping or drop outs, giving a delay range of 0.51 - 7.31ms, perfectly in Electric Mistress territory.

Whether or not the MN3001 can provide a signal at that speed re gain and fidelity is another matter, but I am impressed the signal doesn't "click" out and back in at the top at that speed  :)

The one thing left I can't yet investigate without a scope would be to look at the clock rate (Or better "delay time") sweep in terms of VCO / MN3007 in terms of shape. I know the EM LFO is triangular, and I know the EM "perfect" shape for the resulting delay time perception is "hyper triangular" (sharp at the top, rounded at the bottom).

Does anyone already know what the Current Lover and/or EM3207 sweep shape is vs the Electric Mistress ?

Listening to this now really shows the greatness of the whole circuit, with the added volume stage tacked on the end and, to my ears more crucially, the retention of the high end of the signal through the pedal, stunning!



Mcentee2

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Re: Current Lover 2015 Clock Range Frequencies
« Reply #2 on: June 06, 2018, 03:33:41 AM »
I know the vol stage Opamp is an internal set and forget, but I would like to have some form of control over the CL high end output as it is very trebly on my set up (yes, I know this is like the EM it is moddelled afeter :)  )

Can anyone offer any guidance as to the best place/type of treble cut control to the 2015 circuit ?

The output stage is a simple opamp buffer/gain set up, so am not sure whether to put another simple low pass pot/cap filter before that or after it (like a rat) ?

I was thinking about that 100pF feedback cap and trying to figure out if that could be made variable ?

« Last Edit: June 06, 2018, 03:38:03 AM by Mcentee2 »