@wg_ski
I am nearly at the end of building baxandall tone control and I have a hard time finding out what type of wiring would be the best for potentiometers.
In last tone control you recommended me using pots in 2wire configuration, twisted pair and noise indeed was zero.
Here I must use pots in 3wire mode.
Should I still use twisted pair and 1 wire along? What two wires should be twisten? or should I do something else?
I am nearly at the end of building baxandall tone control and I have a hard time finding out what type of wiring would be the best for potentiometers.
In last tone control you recommended me using pots in 2wire configuration, twisted pair and noise indeed was zero.
Here I must use pots in 3wire mode.
Should I still use twisted pair and 1 wire along? What two wires should be twisten? or should I do something else?
Twist all 3. Or better yet use PCB mount pots. Even solder-eye types can be mounted to a perf board. This one was used with solder types - I just mounted little solid wire pigtails to each lug, then mounted to the board.
When doing a tube amp with PTP, I build the whole RC network up on a terminal strip right under the pots. Then twist the center and feedback legs going to the grid and plate coupling cap. The input side then comes from another tube socket. In your case it all goes back to a common circuit board.
When doing a tube amp with PTP, I build the whole RC network up on a terminal strip right under the pots. Then twist the center and feedback legs going to the grid and plate coupling cap. The input side then comes from another tube socket. In your case it all goes back to a common circuit board.
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Ok, thank you for clatification.
I would mount pots to board, but space is a big issue. It could be done with some fiddling tho... If noise will be generated, I will go for it.
I would mount pots to board, but space is a big issue. It could be done with some fiddling tho... If noise will be generated, I will go for it.
Ok.
I did the tone control, but no mather how I tuned it, it changed my eq curve too much, sound was not close at all. Noise was not present with extended wiring for pots.
Now I implemented tone controls in 4th stage of my "fixed eq curve preamp" and it is good.
I noticed that vocals are too silent on some music, especialy female vocals. So I will probably loose that 1khz dip, because I think that this is the cause.
In the end what will remain, will probably be just baffle step compensation (as you suggested at first) plus a little rolloff at highs.
What I did is probably correct, but then there comes the trade offs...
I did the tone control, but no mather how I tuned it, it changed my eq curve too much, sound was not close at all. Noise was not present with extended wiring for pots.
Now I implemented tone controls in 4th stage of my "fixed eq curve preamp" and it is good.
I noticed that vocals are too silent on some music, especialy female vocals. So I will probably loose that 1khz dip, because I think that this is the cause.
In the end what will remain, will probably be just baffle step compensation (as you suggested at first) plus a little rolloff at highs.
What I did is probably correct, but then there comes the trade offs...
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Update:
After much testing & listening, best result is given by keeping the the 1khz dip, just making it smaller.
Now I have new problem, that I didn't care to bother with until now -group delay... lpfs are just making too much of delay... will see what I can do.
After much testing & listening, best result is given by keeping the the 1khz dip, just making it smaller.
Now I have new problem, that I didn't care to bother with until now -group delay... lpfs are just making too much of delay... will see what I can do.
When you give a speaker the “thump test”, you just want to hear a single low frequency damped tone. If it sounds echoey or boxy, that indicates exciting multiple higher order modes. You want all those damped out or they will eventually drive you up the wall. I usually staple a thin (2”) layer of fiberglass on 3 sides of the box. Mid range sub-enclosures can be worse, as that pushes all those frequencies where it happens up, and are harder to get rid of.
Ok, thank you for info. It' s so hard with this speaker. You look at it and it plays differently. It's so sensitive to eq & different music genres.
I installed deadening on both side walls and it sounded so good, then house music came up... with zero bass, so I removed deadening from the sides.
I will experiment further, but probably settle with deadening just on back wall.
I installed deadening on both side walls and it sounded so good, then house music came up... with zero bass, so I removed deadening from the sides.
I will experiment further, but probably settle with deadening just on back wall.
And then there are the highs, if I don't slightly overboost the lows, it sounds like a small speaker... bright, I can turn the highs down and it will still sound like that.
It gets much better at higher volumes.
After alot of testing I can confirm that this is rather the characteristic of the driver itself. Because IT IS small.
I am limiting the range of tone control to appropriate levels as I go.
To one observing this, it would probably be clear as a day that I should forget everything and start over with a different speaker, but I did and learned so much and on the long run sound is shaping in my favour, there is just alot of trial & error and I want to achive this, just to prove it to myself.
Speaker grill makes it a little bit better, but I will experiment with cloth to see how it turns out.
I think that enclosure passes the thump test with deadening on the back side, but it is really hard to say due to it's size, port output is really quiet.
It gets much better at higher volumes.
After alot of testing I can confirm that this is rather the characteristic of the driver itself. Because IT IS small.
I am limiting the range of tone control to appropriate levels as I go.
To one observing this, it would probably be clear as a day that I should forget everything and start over with a different speaker, but I did and learned so much and on the long run sound is shaping in my favour, there is just alot of trial & error and I want to achive this, just to prove it to myself.
Speaker grill makes it a little bit better, but I will experiment with cloth to see how it turns out.
I think that enclosure passes the thump test with deadening on the back side, but it is really hard to say due to it's size, port output is really quiet.
I removed the deadening from the back wall, now it only remains on 1 sidewall where driver is really close to it. Design of the grill didn't allow for driver to be moved away.
Also I lifted 1.5kHz for almost a dB.
Best sound so far, much better.
Also I lifted 1.5kHz for almost a dB.
Best sound so far, much better.
I went 2-way. It's alot better.
I was not happy with the high end side of sound. I remmembered that I have tweeters from 2007 Opel Astra in the garage. Those tweeters play really nice.
I don't know the manufacturer, it's labeled as General Motors.
If anyone have any info on these, please let me know.
Radios for these cars were made either by Blaupunkt, Delphi or Becker, output was 4x35w if I remmember correctly.
I quickly wounded 0.08mH inductor, tweeter has 4.7uF capacitor installed. I will need to attenuate tweeter a bit, I will also try Zobel network.
It sounds good.
I was not happy with the high end side of sound. I remmembered that I have tweeters from 2007 Opel Astra in the garage. Those tweeters play really nice.
I don't know the manufacturer, it's labeled as General Motors.
If anyone have any info on these, please let me know.
Radios for these cars were made either by Blaupunkt, Delphi or Becker, output was 4x35w if I remmember correctly.
I quickly wounded 0.08mH inductor, tweeter has 4.7uF capacitor installed. I will need to attenuate tweeter a bit, I will also try Zobel network.
It sounds good.