Yet another Volume controlers and source selections


Congratulation !
And Pryanick : I like those MLT resistors , give so sweet sound !
I will post some time soft and schematics with one atmega16 with r/2r 6 relay for volume and 7 relay for bass and 7 relay for treble controller (exactly like your but extended for 7 relay each tone control : bass and treble for 0dB in the middle and -5dB, -10dB ,-15dB and +5dB , +10dB , +15dB on both ).
It was made by me in year 2007 but never posted ....
here the schematics :
http://i31.tinypic.com/necfb5.jpg


Hi
This week end I finished passive preamp with tone control.
Original source code by danzup I took here
http://www.diyaudio.com/forums/anal...controlers-source-selections.html#post1907172

Thanks Dan for the original passive preamp schematic


Congratulation !
How do the passive tone controller sound ?
Mine not ready , as I am involved now in another urgent project !
I see you only connected the + dB side ...
I must find time for finishing this project .

got few above posts regarding the tone + volume controls with relay r-2r

Is it supposed to be passive circuit between audio source and main amp or do we need a buffer (fet or opamp) between the tone control and volume control modules..
In one of the above circuits tubes were used between tone and volume control parts and in other they are directly connected without any buffer.

Regarding LDR-LED based could you please suggest a good option.. in the forum there are different circuits given some requiring matching ldrs some dont ... and some places its given that LDRs are non-linear and introduce distortion ... so is it better than relay r-2r based volume-tone controls which only have resistors which are linear

thanks and regards
s sarath
 
Sarath,

I have documented a lot of information in wiki section. Have a look, this may answer many of your questions.
Building Vicol Audio R-2R volume controller - Part 1 - diyAudio

Regards,
Tibi

Hi Tibi,

Thanks for the wiki link.
It has detailed info regarding the volume control part.
I am interested on adding tone controls also, is there any more info regarding similar tone control part also?
Seen few posts in this thread and have some doubts as mentioned couple of posts above (#921).

thanks and regards
S Sarath
 
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China board

If you don't need the R2R I made software to the cheap eBay version
check my blog here : Royalsystems Projects Blog
Hello!
Following your instructions i have repaired china board by atmega with your code. In NEC code very interesting comment: 'asta e cea mai mare smecherie !
what you mean?
i`m beginner in bascom. Can you give me code with no "backlight off"? i using this out for external relay for on\off amplifier.
my email: biturbo420@gmail.com.
thanks.
 
Thanks, i idid translate it. I interested why it present in Bascom code as comment?

Be cause you see the comment like "Asta e cea mai mare șmecherie "
can be from a beta tester "we change the code and it's working"
I have many friends that dont write in english all the time when we debug a code at skype or via my chat site

General Interrupt Flag
Register – GIFR

GIFR=64 = 01000000 the 6 bit is set

• Bit 6 – INT0: External Interrupt Request 0 Enable
When the INT0 bit is set (one) and the I-bit in the Status Register (SREG) is set (one),
the external pin interrupt is enabled. The Interrupt Sense Control0 bits 1/0 (ISC01 and
ISC00) in the MCU General Control Register (MCUCR) define whether the external
interrupt is activated on rising and/or falling edge of the INT0 pin or level sensed. Activity
on the pin will cause an interrupt request even if INT0 is configured as an output. The
corresponding interrupt of External Interrupt Request 0 is executed from the INT0 Interrupt
Vector

more info at atmel datasheet for M8515 http://www.atmel.com/Images/doc2512.pdf
 
Pardon me, if this has been discussed earlier in this topic, but I couldn't find it via search. Is this R-2R attenuator logarithmik? Is it possible to calculate different kinds of input impedances, step sizes, etc. by using this calculator: Logarithmic Attenuator Calculator and changing the resistor values?

If anybody has an extra usbtiny AVR programmer, I would be more than happy to purchase one. The shipping costs to Finland are astronomical from Adafruit webshop...:eek: