EHX - Bass Blogger  [schematic]

All about modern commercial stompbox circuits from Electro Harmonix over MXR, Boss and Ibanez into the nineties.
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Bernardduur
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Post by Bernardduur »

So I got this pedal as I am really a bass player and wanted to see if it would fit my needs.....

it is a weird pedal.......

On drive mode the volume knob does not function.
The unit cannot be daisy chained.
The filter sounds great on bass!!
The fuzz mode is simply wonderfull, like a less compressed muff

The voltages are measured with a CIOKS baby which gives 8.9V DC

Off: V+ = 0.09V; V- = 0.00V
On: V+ = 4.63V; V- = -3.96V
Bass Blogger.JPG
'No more....... loud music.......'
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karul
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Post by karul »

1000 posts Bernardduur !!! :thumbsup

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Bernardduur
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Post by Bernardduur »

:), didn't even seen that :)
'No more....... loud music.......'
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Post by ruggine »

Thank you very much for the circuit. What's the value of the inductance L1?

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Blitz Krieg
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Post by Blitz Krieg »

cannot be daisy chained?

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Bernardduur
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Post by Bernardduur »

Blitz Krieg wrote:cannot be daisy chained?
Nope!
'No more....... loud music.......'
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mictester
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Post by mictester »

Any distortion effect before it is going to be affecting the envelope detection, and the output impedance is a bit high for a modern device... You should be able to put things after it.
"Why is it humming?" "Because it doesn't know the words!"

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mictester
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Post by mictester »

mictester wrote:Any distortion effect before it is going to be affecting the envelope detection, and the output impedance is a bit high for a modern device... You should be able to put things after it.
Having said that.... the output Z is lower that I thought at first glance - why won't it daisy chain?
"Why is it humming?" "Because it doesn't know the words!"

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Dirk_Hendrik
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Post by Dirk_Hendrik »

Am I the only one getting a headache from this circuit and getting more and more suspicions on the (lack of) correctness? Let's take an easy example: The way the parallel darlingtons that seem to drive the red LED do so from the input of an opamp. Someone willing to explain the function?
Sorry. Plain out of planes.

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captaincav
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Post by captaincav »

Dirk_Hendrik wrote:Am I the only one getting a headache from this circuit and getting more and more suspicions on the (lack of) correctness? Let's take an easy example: The way the parallel darlingtons that seem to drive the red LED do so from the input of an opamp. Someone willing to explain the function?
Those Darlingtons are the output buffers built into the LM13700 which are more specifically operational transconductance amplifiers which can kinda be thought of as a pair of CA3080's and the Darlingtion output buffers.

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Bernardduur
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Post by Bernardduur »

Bass Blogger.JPG
I've had some time and checked the schematic

Believe now it is fine!
'No more....... loud music.......'
Follow my love for pedals and amps on https://bernardduur.blogspot.com and https://www.instagram.com/bernardduur1

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