Dear sir,
I am planning to build this tone control pcb. I wanted ask you where can i put volume control pot? at the input or at the output of the tone control? and what is the value of the volume control pot ? I would be using the 10k pot version of your pcb given elsewhere in the thread.
regards
prasi
Dear Mile sir,
I attaching your stereo tone control pcb with 10k pots for bass and treble and also including the volume control pot. can you please check it and tell me if there are any errors?
regards
prasi
Attachments
Dear Mile sir,
I made our stereo tone control PCB with volume control also. pl find attached the pic. Can you suggest any corrections?
Attachments
Thanks for your quick reply Mr. Mile. Please find attached herewith revised PCB. I hope I have done this correctly this time.🙂🙂
reg
prasi
Attachments
good
: Bombilla:: Bombilla:: Bombilla:: Bombilla: congratulation: Bombilla:: Bombilla:: Bombilla:: Bombilla:
: Bombilla:: Bombilla:: Bombilla:: Bombilla: congratulation: Bombilla:: Bombilla:: Bombilla:: Bombilla:
Dear Mile sir,
I made tone control PCB as per the design(post no.505, which you okay-ed). when i connected it to power amplifier (APEX LM3886), I hear a lot of distortion, which is very clearly audible at low volumes. If I don't use the tone control and just use a volume pot on amplifier input, the sound is very good.
Can you help identify the problem with your tone control circuit?
reg
prasi
Hi,all circuit of mile sir is ok tested .some novice guy made apex crossover and ml3 and claim that circuit is not working and distortion and hum is very high but when i made ml3 and all crossover and feel that these mile sir design is high quality and best many of comercial costly brand and i giving you all statement this is not diy circuit this is apex audio.
Hi Rohin,
I agree. I must have made some mistake while assembling the componenets on pcb. could you tell me what is the polarity of C9, C10 caps. PCBpost #505.
reg
prasi
I agree. I must have made some mistake while assembling the componenets on pcb. could you tell me what is the polarity of C9, C10 caps. PCBpost #505.
reg
prasi
anyone care to reply?. I have tried all other optons but to no avail. I have replaced caps, I/C, etc still the problem persists. At low volume, the sound distortion is quite audible, at higher volumes, its not apparent.
reg
prasi
reg
prasi
if your tone bass and treble working then it is due to ground .your tone body need ground wire.do the proper earth and try this tone control again .this is common problem if it only hum.it may be due to bad power supply too.i think you should post picture.
hi rohin,
pl find attached the photos of tone control and the amp. PS ground is connected to the tone control ground which in turn is connected to the signal ground through a trace as per the design in post #505. I have checked and rechecked all wiring and it is ok. dont know whats wrong.😕
reg
prasi
Attachments
you have to ground your amp chassis well.i don't think that A10 k good for that. use B10 k there is difference in a and b.lin and log tone are different.some time bad ground design of pcb cause this problem.may you fix it soon.did you check resistance some time they bad too.tone body earth is different from pcb desing you have to earth it with wire.your work is clean and good.
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Hi.
I have already checked the pot. When I just connect the A 10k volume pot on the input, the sound is just fine. When I use tone control circuit the distortion occurs.
Power supply is 12 v ac regulated to 12 v DC by 7812 and 7912 regulators. Should I ground the body of all pots (bass. Treble. Volume) to ground connection?
Another aspect. Should I use 100nF cap in parallel to 10ohm res to connect to the signal input of tone control PCB?
I tried this also today , but no improvement. Distorted sound at low volume and at high volume, its not so apparant. Dont know what to do. Is it due to the fact that I modified the original APEX PCB to include volume pot? dont know. :-(
reg
prasi
Hi all,
Just when i had lost all hope of ever completing my first ever diy integrated amp, Eureka!. Something clicked .
this moment happened when i was pondering the events of building this amp and where i might have done wrong. when i had just used the volume control on the i/p of the amp, sound was very nice. then i etched my tone control pcb with thermal toner transfer method and soldered on all the components. unknown to me, PCB track on the supply input (because the tracks pass so close to each other along the center of TL074) was shorted and when switched on the amp, there was a thump sound (uncharacteristic, because I know this apex gainclone is thump free due to the zener diode on mute pin!). I just ignored this to my peril, and since the pcb was not working, i got it screen printed from someone and went on to build my second tone control pcb. when i assembled everything and switched on, everything was working except that the sound was distorted especially at low volume levels and at higher volumes it was not so apparent.
It must have so happened that the uncharacteristic thump that i heard with my first home etched pcb was actually the woofer being blown / torn and at higher volumes the tweeter took over and overpowered the woofer distortion. swhishhhh!. fortunately the speakers were commercial and not so hi-fi.
when just i had lost all hope of ever completing the project,(believe me i tried everything; changed caps, TL074 i/c's by dozen, grounding schemes, and as rohin suggested, grounding of volume/tone pots and what not!!, i was even planning to import TL074 i/c from RS components UK!), i just tried on with another speaker that i had lying around and voila, the sweet sound started pouring out of it.
thus problem resolved!, even as i am writing this, my favourite song is playing on a wonderful amp built my me and my home made hi-fi speakers.
all credit goes to Mr. Mile Slavkovic, I so fondly call him Mr. Mile Sir of APEX audio .
You sir are truly an invaluable asset of DIY audio world.
Thanks again!! keep up the good work!!
best Regards
Prasi
Hello Mr. Mile sir.... My amplifier based on your lm3886 and stereo tone control is working fine. But I feel that bass is lacking. And sound seems very harsh on ears. I have used all components as per the layout. Should I change any components to make it pleasing to the ears?
Reg
Prasi
Reg
Prasi