speaker wire with inductor?
My mod is so far working but not complete. I managed to take off the caps and followed stealth mod per panomaniac site.
It is unclear to me whether
1. I need to keep the inductor ring on the speaker wire connection (as in the original t-amp?). Looks like most of the pictures have eliminated it.
2. do I keep the original tiny cap acorss the speaker terminal wire?
gychang
My mod is so far working but not complete. I managed to take off the caps and followed stealth mod per panomaniac site.
It is unclear to me whether
1. I need to keep the inductor ring on the speaker wire connection (as in the original t-amp?). Looks like most of the pictures have eliminated it.
2. do I keep the original tiny cap acorss the speaker terminal wire?
gychang
Both of those are final output filters to eliminate radio frequency noise, especially the harmonics up in the FM broadcast band.
They are not need for the amp to function, but they do remove some RF noise from the speaker lines. It' going to depend on your other audio, video and radio components (and wiring) as to whether you need to keep them or not.
They are not need for the amp to function, but they do remove some RF noise from the speaker lines. It' going to depend on your other audio, video and radio components (and wiring) as to whether you need to keep them or not.
panomaniac said:
thanks panomaniac for all your work on this addicting DIY.
My stealth mod works, but with one minor problem. As soon as I turn on, there is a hiss (from both speakers), that does not change with the volume change.
I have tried 2 other set of speakers, and 2 power supplies... Any ideas?
It has been an exciting advanture, bass is definitely there...
thanks,
An externally hosted image should be here but it was not working when we last tested it.
gychang
Hi gychang, there are a couple of things that you can do but maybe the hiss is coming from the input wires, are they shielded? They don’t appear to be.....
These Sonics are set-up with a bit of gain, which exacerbates any pickup on the inputs.
You can also change the feedback resistors to bring it down to 1:1 which would help but not recommended for beginners…
Once you have it installed in your nice new metal case with short shielded wires.... it should be fine.
These Sonics are set-up with a bit of gain, which exacerbates any pickup on the inputs.
You can also change the feedback resistors to bring it down to 1:1 which would help but not recommended for beginners…
Once you have it installed in your nice new metal case with short shielded wires.... it should be fine.
Lostcause said:Hi gychang, there are a couple of things that you can do but maybe the hiss is coming from the input wires, are they shielded? They don’t appear to be.....
These Sonics are set-up with a bit of gain, which exacerbates any pickup on the inputs.
You can also change the feedback resistors to bring it down to 1:1 which would help but not recommended for beginners…
Once you have it installed in your nice new metal case with short shielded wires.... it should be fine.
none of the wires is shielded (I have some shielded microphone wires!!)
1. input wires - are u referring to wires from RCA jacks to the volume knob (I have alligator clips for testing)?
2. is there a instructions on how to change resistors down to 1:1, it does seem to setup for higher gain? (I have some metal, carbon resistors) and I can safely remove SMD...
thanks very much for information.
gychang
Shielded Wires
Yes, the wires from the RCAs should be shielded. You maybe able to reduce the hum by twisting the two wires for each channel together. Doing so may lead you to the source of the problem.
Try to get the input wires away from the power supply wires and the speaker wires. This may reduce hum.
The shorter the input wires the better if the wire is not shielded. The wires act as antennas.
Yes, the wires from the RCAs should be shielded. You maybe able to reduce the hum by twisting the two wires for each channel together. Doing so may lead you to the source of the problem.
Try to get the input wires away from the power supply wires and the speaker wires. This may reduce hum.
The shorter the input wires the better if the wire is not shielded. The wires act as antennas.
Re: how to attenuate input sensitivity?
If so, then you have something wired up wrong, like a bad ground on the pot.
From your photo, it looks like everything is wired correctly, so I'm not sure why the problem. Unless it's simply a bad connection somewhere, or the pot is bad.
gychang said:
If so, then you have something wired up wrong, like a bad ground on the pot.
From your photo, it looks like everything is wired correctly, so I'm not sure why the problem. Unless it's simply a bad connection somewhere, or the pot is bad.
ongoing saga
stealth mod was working, when I tested it before I put in the case. Before I put in the case, some hiss was heard as soon as the power came on otherwise music sounded fine and now I have put in the shielded cable from the RCA input per suggestion.
I had to reconnect and permanently solder the power switch, pot, etc. Now the power comes on but absolutely no sound from the either speaker, not even a tiny hiss or click when I power on the switch.
can someone find an obvious error? I have a DIMM meter (mainly checking ohms, connectivity with beeps, etc). Is there an easy way to trouble shoot?, thanks.
gychang
stealth mod was working, when I tested it before I put in the case. Before I put in the case, some hiss was heard as soon as the power came on otherwise music sounded fine and now I have put in the shielded cable from the RCA input per suggestion.
I had to reconnect and permanently solder the power switch, pot, etc. Now the power comes on but absolutely no sound from the either speaker, not even a tiny hiss or click when I power on the switch.
can someone find an obvious error? I have a DIMM meter (mainly checking ohms, connectivity with beeps, etc). Is there an easy way to trouble shoot?, thanks.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
gychang
Member
Joined 2003
Your output is obviously shorted through the chassis. Also, the input ground connected to the chassis will likely make a lovely hummmm sound.
Isolate your connections. And you can remove the ferrites from the audio output, they won't be of any use there (that's what the caps across the output terminals are for).
Isolate your connections. And you can remove the ferrites from the audio output, they won't be of any use there (that's what the caps across the output terminals are for).
Connections
To restate what Panomaniac said. Make sure all the input and speaker connections are electrically isolated from the aluminum chassis. Place isolation washers or some non-conductive material between the speaker terminals, the RCA connectors and the aluminum.
There should be resistance between the speaker terminals and the RCAs. If you get zero resistance the connections are not appropriately isolated. Check all connections twice to insure there are no short circuits.
To restate what Panomaniac said. Make sure all the input and speaker connections are electrically isolated from the aluminum chassis. Place isolation washers or some non-conductive material between the speaker terminals, the RCA connectors and the aluminum.
There should be resistance between the speaker terminals and the RCAs. If you get zero resistance the connections are not appropriately isolated. Check all connections twice to insure there are no short circuits.
Re: Connections
Thanks!!, for all your help, everyone, especially paromaniac and his site.
My mistake was using the speaker binding post (since I had it around from building speakers) and using it for the amp build. Apparently it was shorting out.
Now it is singing!, I think I can take it from here...
gychang
Thanks!!, for all your help, everyone, especially paromaniac and his site.
My mistake was using the speaker binding post (since I had it around from building speakers) and using it for the amp build. Apparently it was shorting out.
Now it is singing!, I think I can take it from here...
gychang
Hi guys!
Long time no see. This thread is apparently still running which is great - LOTS of nice sound for no money.
When I se all the wiring I cant resist you from this site: http://www.svalander.se/teknik/kablar/flata.htm
It´s in swedish and look at the pictures. Make internal connectors, external input cables and speaker cables with this technique will do wonderful thing to your sound.
Two wires for each pole = four wires for any type of cable (speaker, internal, input), and connect to RCA:s of fairly good quality.
If you want to go sheap, use CAT5 cables that you take the outer insulation of, untwin and four-twin together as shown. For speaker cables use almost whatever that has copper inside (if you don´t have silver cables hanging around) - almost anything will be better than mid price bought cables.
There is cables for input and speaker cables to buy if you like to. If you don´t speak the language (just 8 miljons does) I can help you.
Sheers!
Long time no see. This thread is apparently still running which is great - LOTS of nice sound for no money.
When I se all the wiring I cant resist you from this site: http://www.svalander.se/teknik/kablar/flata.htm
It´s in swedish and look at the pictures. Make internal connectors, external input cables and speaker cables with this technique will do wonderful thing to your sound.
Two wires for each pole = four wires for any type of cable (speaker, internal, input), and connect to RCA:s of fairly good quality.
If you want to go sheap, use CAT5 cables that you take the outer insulation of, untwin and four-twin together as shown. For speaker cables use almost whatever that has copper inside (if you don´t have silver cables hanging around) - almost anything will be better than mid price bought cables.
There is cables for input and speaker cables to buy if you like to. If you don´t speak the language (just 8 miljons does) I can help you.
Sheers!
almost there, minimal hissing...
hooked it up to my PC, USB soundcard, and my fullrange speaker.
I notice minimal hissing noise as soon as the amp is turned on, both speakers, sound does not change with volume knob. Much improved since the input wires were changed to shielded microphone wire. Compared to another t-amp (amp3), the hiss can be heard.
It may still be a ground issue, changed the power supply, and speakers without change in the hissing noise. Anyone have any suggestions?, it does sound good once the hiss is ignored.
gychang
hooked it up to my PC, USB soundcard, and my fullrange speaker.
I notice minimal hissing noise as soon as the amp is turned on, both speakers, sound does not change with volume knob. Much improved since the input wires were changed to shielded microphone wire. Compared to another t-amp (amp3), the hiss can be heard.
It may still be a ground issue, changed the power supply, and speakers without change in the hissing noise. Anyone have any suggestions?, it does sound good once the hiss is ignored.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
gychang
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