OT Pictures!

[nexekho]

[nexekho]

Now all it needs is... well, frankly, the CPU that actually does anything.

[Nikolay]

Hi, guys. I finish my new simple custom looper
Here is a shot:



Niki

[tasos]

Hi, guys. I finish my new simple custom looper
Here is a shot:

Niki

Great!
So how do you make sure all the labeling is in place(not in axis)

[deadastronaut]

@james: come on...give us a clue you teaser..

[nexekho]

@james: come on...give us a clue you teaser..

Ha!   

It's just a microcontroller board; a little 5532 preamp to the ADC, ATMega328P, two 8-bit PWM ports with a resistor divider to get a rough 16 bits, a 5532 buffer, a Chebyshef lowpass to filter the PWM to something audible, a 5532 post amp, then output!  One op amp is spare and might be used for buffering a CV or expression jack further down the road.  Other than that, a 4017 hooked up to a 7-segment display and two LEDs sinking current into one of the microcontroller pins and some buttons for input.  Just was a bit inconventient to need both an input and output buffer to use the Arduino.

[deadastronaut]

  you liost me on the first sentence....lol....i knew i shouldn't of asked. 

[artifus]

... I've found myself paying attention to what the stage feels like, especially when I wear shoes with thinner soles.

i've noticed a few barefoot bassists, particularly in the jazz world.

[a soBer Newt]

My first baked PCB, came out way better then I thought it was going to, rather proud of my self. Less than six months ago did not know how to do SMT and now look at me!

[tasos]

What are you making?

[a soBer Newt]

What are you making?

Its a mic pre that AEA makes, the RPQ 500, I am there intern so I am learning about small run SMT prototyping.

[Earthscum]

This made me laugh...
_{(Don't really do this)}

[tubelectron]

This made me laugh...
_{(Don't really do this)}

DO NOT DO THIS - the battery has all the chances to explode !!!

A+!

[tubelectron]

... And, oh, I was heavily into restoring vintage tube VTVMs these short and recent times :




OK - Big contrast : that's not SS, SMD nor microcontroller device, but somewhere musical-maintenance-tubes related...

A+!

[Seljer]

I want to share this somewhere. I made a phono preamp and bipolar power supply. The rotary switch gives you three different gain settings (+30,+40,+50dB), I still need to find a knob somewhere.
This finally enables me to listen to all my dad's cheesy records 



And the turntable I'm using it with, a lovely 1970s Technics. Had to spray a little bit of contact cleaner into the speed adjustment potentiometers and it now spins without any trouble.

[tasos]

Hey could you tell us more about the phono preamp?

[Seljer]

Hey could you tell us more about the phono preamp?

No problem! I followed the schematic from dano's site http://beavishifi.com/articles/phono-preamps/ . The RJM Audio one to be specific, I used the 'more accurate' component values for RIAA eq curve in the feedback loop as listed on the original page (http://phonoclone.com/diy-pho5.html). No audiophile parts, an NE5532 opamp, just regular film caps all round (paralllel with a bipolar electrolytic on the output) and whatever resistors I got in the right values. Sounds fine, no clipping with the +-9V power supply (I probably could have done+-12V with the transformer putting out way more at so little load but I purchased 9v linear regulators so I'm stuck with that for now), very little noise from the preamp itself. If I dime everything you I get some some 50hz hum but I think thats coming from the actual turntable...and then theres the continous battle with dust and such on the actual records.

I have an eagle layout if anyone wants to try making it (I built it on perfboard but I used the program to get the basic layout done).

[tasos]

Hmmm thanks...
I am interested because i am making a bass head and when i connect my bass directly to the power amp it is very quiet(the power amp is 200watt)
However when i connect my bass in any of my mixers(i have two) and then to the power amp the sound from the speakers is LOUD!

Do you think a phono preamp would do the job?
My power amp is http://sites.google.com/site/quasisdiyaudiosite/nmos-series/nmos200-1 to220 version...
Any help would be really appreciated

[Seljer]

Hmmm thanks...
I am interested because i am making a bass head and when i connect my bass directly to the power amp it is very quiet(the power amp is 200watt)
However when i connect my bass in any of my mixers(i have two) and then to the power amp the sound from the speakers is LOUD!

Do you think a phono preamp would do the job?
My power amp is http://sites.google.com/site/quasisdiyaudiosite/nmos-series/nmos200-1 to220 version...
Any help would be really appreciated

The phono preamp's purpose is other than boosting the millivolt signal from the record player is to apply a special EQ curve (records are manufactured with a treble boost which is then removed when you play them and in doing so, you avoid high frequency noise http://en.wikipedia.org/wiki/RIAA_EQ). So...it's a one trick pony for this specific purpose (hooking up the turntable to the computer to digitize some records).

But a simple opamp gain stage would work fine for what you need to do (go find the schematic for the MXR Microamp or just read up on operational amplifiers ) ...there are a couple of designs for dedicated bass preamps out there too (with extra tone controls and such).

[egasimus]

Tasos, check out some JFET bass preams, e.g. Albert Kreuzer's.
http://www.albertkreuzer.com/preamp_onboard.htm