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Hi guys, long time to post here.
My good old friend Ettore_M gave me as a present his amazing engraved Engineer's thumb compressor, check this marvelous build.
He did an outstanding job.

http://www.madbeanpedals.com/forum/index.php?topic=11664.msg105300#msg105300

So I was thinking adding a blend knob to this great compressor, so I took JMK panner and put it with the compressor.
http://jmkpcbs.com/wp-content/uploads/2014/03/Panner.pdf
Of course it didn't work as expected... so I started reading posts in the forum.
Everyone said that compressor has phase inversion and obviously we can't mix-blend different phase signals.
The result was volume drop and tone sucking.
After that I put an inverting amplifier before the volume control of the compressor so I can flip the phase 180 degrees.
The result was the same as before, in the middle position where is 50% wet 50% dry I had again volume drop and tone sucking.
Since now the phase is the same I am thinking there is probably an impedance issue.

Do I have to omit the inverting op-amp and put an emitter follower buffer after the compressor volume control? Any thoughts on that?

I am gonna visit messe frankfurt this year.
Any others who are gonna go?
Maybe grab a beer together and talk nerdy pedal stuff...

I am visiting Berlin next week and I was hoping some points regarding guitar gear shops or anything related to music like
nice places with live rock-blues-jazz bands.
I believe Thomas and Tremster are from Berlin, so guys any help will be appreciated.
I only find two guitar stores, checkpoint guitars and Berlin guitars.
Now as far live band pubs I don't know anything.

Cheers,
Panos.

Currently I am designing a bbd analog delay based on dm-2 and I was thinking adding a tone control.
My thought is that probably the best position to put the high pass filter is after the signal expansion, but I am not 100% sure where should I put it,before or after the mixing stage?
In which place will be more audible differences?
I think there is a high pass filter after the mixing stage with 3.4 Hz cuttoff.
Do you think should I change those values?

Finally I ve got after a lot of time and search my new analog delay,
Its a maxon Ad-900 with 4 mn3008 delay in perfect condition.

Also a friend of mine gave me his old analog scope.
Its a dual channel Hameg 150MHz BW scope.

Really excited for both of them,
don't know really with which one should I spend more time.

Finally they make it....
I was trying to find an old silver jubilee of the back days without any luck.
The only downside is the price, obviously....
and that there is only the 100/50 watt head.
If they make the 50/25 watt head I will definitely buy one.

http://www.premierguitar.com/articles/21873-marshall-amps-reissues-the-silver-jubilee-2555-stack

So this is my story :
I found a deal on a FB group UK guitar/Amp/Gear Exchange, nothing mojo or very expensive.
It was a dunlop uni-vibe stereo chorus, seller asking for 50 pounds and I kindly ask him if he sells outside UK.
He answered me of course and that the shipping cost is on me.
So we agreed on 60 pounds, I ve send the money to him via Paypal and everything was ok.
By the time I made him friend on FB so he can send me the tracking number and talk if anything goes bad.
Day1 passes nothing, I said ok its holiday so I think let the man have fun.
Day2 passes and I send him kindly if he can send me the tracking number, after a couple hours answers saying that he didnt make to the post office and he will send it tomorrow.
Day3 gonne and nothing.
Day4 I send him again kindly what is going on, nothing....from our conversation I can see that he read my messages but still nothing....
After 5 hours he answers me that this is my tracking number and that I need extra 5 pounds for the shipping cost.
I said my shelf ok everything went well and the guy didnt rip me off so I thanked him and I kindly ask him why did you take so long to send me a tracking number or answer my messages.
And then he said me very rude that "mate, I am working and I dont have time to answer your messages. Your pedal has been sent you have received the tracking number that is all, I am not your friend I am selling you an item that is all. I have unfriended you on Facebook, please The stop messaging me. And send the extra 5 pounds postage ASAP. "

After that I answered him " ok thank you and I will send you the extra 5 pounds"
End of story.

So now I am thinking I wont pay right now his extra 5 pounds but after a couple of days for being a prick, but on the other hand I am thinking why should I do that and becoming like him.

What do you think?

Cheers,
Panos.

Finally I am able  to buy a new digital oscilloscope.
After looking on the net I found that Rigol DS1074Z-S is probably the best way to go.

70 MHz bandwidth, 4 channels, 1G samples/s and built in 25 MHz waveform generator.
Its a bit pricy but I believe worth the extra money.

Do you reccomend something else?

Cheers,
Panos.

What are the benefits if we increase the power supply in a opamp?
Feeding an opamp with bipolar 15v dc comparing to standar 9v dc.
Increasing power supply I think will affect headroom but is there any audible difference?

Can someone explain the purpose of virtual ground using opamp?
For example I see Brian use it on the Stage Fright project.

I am a bit confused about choosing solder from mouser.
The only thing that I am sure is that I used alloy 63/37 and 0.031inch diameter.
I dont know the differences between the active rosin, water soluble and no clean wire solder.
I believe and I am not sure the difference between them is the after solder residue.
I am between those solders

http://gr.mouser.com/Kester/Tools-Supplies/Soldering/Solder/_/N-b11qqZscv7?P=1yzxt4nZ1yzxbyqZ1z0zl9lZ1z0vtnfZ1yzt5jh

Which one should I choose?

I just saw a thread on FBS regarding ROHS compliance.
I believe it is an issue which I'd never think about it.
For start the builder must change to leed free soldering and must find a rohs compliant pcb manufacture or make ENIG finish PCB's, correct?
Also from my point of view this is a limitation to someone who want to use  panasonic MNxxxx BBD chips or germanium transistors.
On BBD chips there is the option of using Rohs comliant cool audio chips but what about germanium transistors?
What do you think about it, are any other options?

I just order an retrograde and I was thinking using PNP instead NPN transistors just like the original.
I will reverse all the caps and feed the board with -9v probably wont face any issues.
Should I make any other changes?
Also regarding the audio transofrmer If I use different ratio turns will be noticeable audio difference?

Cheers,
Panos.

I currently have on my hands a Shin Ei Univibe,
I ve managed to trace the entire pedal but my transformer knowledge is a bit low.
So I don't know which PT should I choose.
The original one has one primary 110V and to secondaries with 14v and 6.3v.
The 6.3v secondary is only for the lamp nothing special.
I would like to find one which has the same specs but with 220-230v primary.
Any suggestions would appreciate.

Cheers,
Panos.

Does anyone have any issues with volume whine when you engage both channels and have maximum gain pots?
It only happens when both volume pots are 12 o clock and when both gain pots are on maximum,
when I roll down a little bit any gain pot or volume pot it disappears.
I have added the High gain mod, just put a 250k gain pot on one side of the effect everything else is stock.
Is that normal for this effect?

This month I am thinking of design a delay with 550ms using 4 mn3008,
all four BBD chips will be on the pcb from the start.
The idea is not to use any daughter boards and not any modulation.
Probably it would be like cloning the m@xon AD 900.
So here is my schematic of the BBD.
I don't believe there is a mistake somewhere but it is always good to check another pair of eyes.

For a misterious reason I don't like daughter boards,
I don't know why, despite that they will make my pcb design easier and could give me the oportunity to change the BBD chips from mn3008 to mn3005.

Any recommendations or changes are welcome.

I just saw today this analog delay,
they advertise that they are using BBD chip with 600ms delay time.
Street price is 150$ 
How is that possible?
Does anyone know what they are using?
Is it like maxon AD series delay?

Panos.

I am just messing around reading some schematics on the net.
I am thinking making a BBD analog delay using 4x mn3008, ( I know there is an already thread about it and also a double delay pcb on shared projects).
My main question is when we want to use 4 bbd chips should we have to use two clocks (mn3101) or only one?
I saw today the schematic of M@xon Ad900 and they used two clocks.

Probably Scruffie will have a answer for that.....

I just finished yesterday building pork barrel,
today i made an A/B test with the original Boss CE-2 and on PB the chorus effect was a little bit different, it was more...
The chorus depth effect was a little too much, I used 22k in the LFO indicator.
Should I decrease the 22k resistor for more normal chorus effect?

This is my first built report with Brian's pork Barrel using mn3007 and 3PRR,
usually I design my own pcbs and send them to OSH park but this time I wanted to get in the world of modulation  without spending 2 or 3 hours on eagle.
I must say that I am used to my designs and this one was a bit tricky for me, but I a must say that worth the extra effort.