volume control with treble and bass - Page 1
Forum section: electronics / projects

author: electronics technician
author_rank: Regular Contributor
timestamp: March 04, 2014, 04:25:11 am
content: this is the circuit i need advice onhttp://www.eeweb.com/blog/extreme_circuits/low-cost-bass-treble-controller-using-op-amp-741i need to know if it has any problems asapi used a replacement transistor for the bc148 which is 2n3904 with pin out EBC with the flat spot facing youi need to know if you can just connect a speaker to it with a signal input and see if it works or do i have to run it through an amplifier firsti would appreciate all the help thanks

author: Tube_Dude
author_rank: Regular Contributor
timestamp: March 04, 2014, 04:54:48 am
content: Quote from: electronics technician on March 04, 2014, 04:25:11 amYou have to run it through an amplifier. The 741 op-amp can't provide enough current to properly drive a speaker.

author: peter.mitchell
author_rank: Super Contributor
timestamp: March 04, 2014, 05:57:42 am
content: you may be able to check it with some small earbuds though.

author: madsci
author_rank: Regular Contributor
timestamp: March 04, 2014, 07:21:51 am
content: Might I suggest, once you get this one working, modifying the unit with a more modern, lower noise op-amp. The 741 isn't considered hi-fi by any stretch these days.

author: w2aew
author_rank: Super Contributor
timestamp: March 04, 2014, 01:23:24 pm
content: Quote from: electronics technician on March 04, 2014, 04:25:11 amOh, I really hate schematics drawn that way!Anyway, the basic circuit is similar to something I used years ago to give me a simple bass/treble equalizer preamp for a microphone I use on ham radio. Of course, I did a video on it. The video shows the design, as well as it's performance.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 05, 2014, 12:03:41 am
content: Quote from: madsci on March 04, 2014, 07:21:51 amthanks for the suggestion i will try it when i get the circuit running i was going to buy the 071 op-amp but didnt know if it would workwould it? idki will try the amplifier part also thanks for the suggestion

author: rdl
author_rank: Super Contributor
timestamp: March 05, 2014, 12:12:15 am
content: QuoteYeah, that's pretty bad.

author: electronics technician
author_rank: Regular Contributor
timestamp: March 07, 2014, 01:47:55 am
content: im having trouble wiring the pots for the treble bass and volume can anyone help me pleasethey are 6 pin dual gang inline pots the two on the right looks the exact same as mine so forget about the rest

author: peter.mitchell
author_rank: Super Contributor
timestamp: March 08, 2014, 06:11:35 pm
content: Quote from: electronics technician on March 07, 2014, 01:47:55 amThe middle pins are the wipers, and the pins to the left and right of the wipers are the complementary resistors.A picture is worth a thousand words;

author: diyaudio
author_rank: Frequent Contributor
timestamp: March 08, 2014, 06:36:02 pm
content: Quote from: electronics technician on March 04, 2014, 04:25:11 amusing a 741 is not recommend at all for an application like this, its a bad choice for a tone control and shouldn't even be considered for new designs for anything unless your doing textbook examples or side by comparisons against a newer op amp.Consider using a NE5532, LM833N or something with a high open loop fast slew rate.Please visit this website if you need to educate yourself on this matter it has everything you need to know. (I know it helped me alot when I was building amplifiers in my youth days off vero board)http://sound.westhost.com/project02.htm

author: electronics technician
author_rank: Regular Contributor
timestamp: March 12, 2014, 12:20:50 am
content: i also need help with wiring the pots for the volume treble and bassThe volume pot is a 6 pin dual gang pot and the other 2 is the same 6 pin dual gang but inlinei found this wiring diagram but i dont know if its correct so i need advice on how to wire them up

author: electronics technician
author_rank: Regular Contributor
timestamp: March 12, 2014, 12:23:55 am
content: Quote from: peter.mitchell on March 08, 2014, 06:11:35 pmthe pots i have are 2- 6 pin dual gang inline and one is normal dual gang 6 pin

author: electronics technician
author_rank: Regular Contributor
timestamp: March 12, 2014, 12:40:57 am
content: will this quad op-amp work az324p-e1 i have this on hand so i dont have to buy it but i dont know if it will work thanks for the reply

author: Hideki
author_rank: Frequent Contributor
timestamp: March 12, 2014, 10:31:04 pm
content: AZ324 looks like a copy of the old LM324, so while it will probably work, it's not something I would want to run my audio through.But... for learning, anything goes. Go ahead and use it!

author: electronics technician
author_rank: Regular Contributor
timestamp: March 13, 2014, 08:17:29 pm
content: lol i will try it and say how it went thanks

author: electronics technician
author_rank: Regular Contributor
timestamp: March 17, 2014, 10:25:59 pm
content: Here is the layout of the potentiometer. The one on the left 1s a 10k and the right is 100ki need help to wire them up as per the schematic