sunn beta lead too quiet

[Isaac]

Just because it says on it that it is, does not mean it is functioning as one. In my experience this has happened to my Sunns from faulty cables connecting to the cabs causing current to draw back into the amp.

I don't understand what you mean by this.

[jues]

i ordered it as a speaker cable. it is a little thicker as an instrument cable. and i believe it is wired different, right?

so what does that mean. how can i find out that it is maybe because of my speaker cable?

[EdBass]

i ordered it as a speaker cable. it is a little thicker as an instrument cable. and i believe it is wired different, right?so what does that mean. how can i find out that it is maybe because of my speaker cable?

An instrument cable is wired the same, and will "function" just like a speaker cable. The difference is that an instrument cable is shielded and uses smaller conductors, generally a small insulated conductor in the center used for the tip of the plug wrapped in a wire mesh sleeve used as a conductor for the ring of the plug. Speaker cable is usually thicker overall, and uses much thicker conductor wire because it is meant to carry far more current than instrument cable does.

Speaker cable is rarely shielded and just two much heavier conductors as I mentioned, like AC lamp cord.
In fact, many people use regular old AC extention cord/appliance cord for speaker cable, including myself on occasion.

Like Isaac, I also have no idea what this is supposed to mean;

Just because it says on it that it is, does not mean it is functioning as one. In my experience this has happened to my Sunns from faulty cables connecting to the cabs causing current to draw back into the amp.

But I can't imagine how it has any bearing on your problem, or for that matter how current could ever "draw back into the amp" regardless of what you used to connect it to a cab.

Even though it would be another one of those "magical" fixes I mentioned earlier, your cable(s) probably aren't the problem. If you are concerned that they could be the problem, just post a picture of the ends of your speaker cable with the jacks unscrewed showing the wiring and someone can quickly confirm if its a speaker or instrument cable.

[Walt-Dogg]

Just because it says on it that it is, does not mean it is functioning as one. In my experience this has happened to my Sunns from faulty cables connecting to the cabs causing current to draw back into the amp.

But I can't imagine how it has any bearing on your problem, or for that matter how current could ever "draw back into the amp" regardless of what you used to connect it to a cab.

Even though it would be another one of those "magical" fixes I mentioned earlier, your cable(s) probably aren't the problem. If you are concerned that they could be the problem, just post a picture of the ends of your speaker cable with the jacks unscrewed showing the wiring and someone can quickly confirm if its a speaker or instrument cable.

Ed, in my experience connecting a solid state Sunn amp to a speaker cab with an instrument cable as opposed to a speaker cable will cause the amp to overheat. I killed my Concert Bass and almost my Concert Lead this way.

[EdBass]

Ed, in my experience connecting a solid state Sunn amp to a speaker cab with an instrument cable as opposed to a speaker cable will cause the amp to overheat. I killed my Concert Bass and almost my Concert Lead this way.

I certainly didn't mean to insinuate that using an instrument cable as a speaker lead was a good idea, in fact it's a horrible idea!
Instrument cable is also higher impedance, I would imagine that the cable itself would get toasty hot if you ran any serious power through it, with enough juice hot enough to melt the insulation and cause a short.
That would take out an amp, no doubt.

I'm sure that the wrong cable doesn't do the amp any good, and may cause it to run hot because you are working it hard trying to push all that current through such a small conductor also, but what I don't understand is what you mean by "causing current to draw back into the amp", or how that would occur.

[Walt-Dogg]

Ed, in my experience connecting a solid state Sunn amp to a speaker cab with an instrument cable as opposed to a speaker cable will cause the amp to overheat. I killed my Concert Bass and almost my Concert Lead this way.

I certainly didn't mean to insinuate that using an instrument cable as a speaker lead was a good idea, in fact it's a horrible idea!
Instrument cable is also higher impedance, I would imagine that the cable itself would get toasty hot if you ran any serious power through it, with enough juice hot enough to melt the insulation and cause a short.
That would take out an amp, no doubt.

I'm sure that the wrong cable doesn't do the amp any good, and may cause it to run hot because you are working it hard trying to push all that current through such a small conductor also, but what I don't understand is what you mean by "causing current to draw back into the amp", or how that would occur.

The cable and amp getting hot is an abundance of current with nowhere to go except back to the amp because it can only go two ways and as you said that instrument cable impedance is higher so less signal can get to the speaker cab and that would explain quiet signal and the amp over heating. I'm not an engineer but I've had all of this explained to me over and over by several techs that are at least somewhat reputable. 

[EdBass]

The cable and amp getting hot is an abundance of current with nowhere to go except back to the amp because it can only go two ways and as you said that instrument cable impedance is higher so less signal can get to the speaker cab and that would explain quiet signal and the amp over heating. I'm not an engineer but I've had all of this explained to me over and over by several techs that are at least somewhat reputable.

The current doesn't flow back into the amp, I think that's where you are confusing everybody.

Here's how it would generally play out; The energy that those restrictive conductors in an instrument cable are too wimpy to pass to the speakers cabinet to be converted into mechanical work will be instead converted into heat.
This heat will focus on the "choke points", most likely the solder joints in the plugs, but with enough juice the entire cable will get pretty toasty.
Given enough juice and/or enough time, the insulators in the cable will melt and cause a dead short. If there is enough power coming from the amp this event may be accompanied with a flash, poof, a whiff of magic smoke; possibly even a small flame.
Sometimes this event will pass mostly unnoticed; that is until part two happens (see below).

Right after that event it's the transistors turn. Transistors outputs do NOT like a dead short, and will very quickly go unstable and into a "melt down" and do their own small scale impression of Chernobyl.

An amp will always get hot when it's running at full tilt, that's why they use heat sinks. But it isn't a case like a backed up up sink, or that somehow current flows backward from the instrument cable into the amp, it's an issue of energy dissipation.
The energy being produced is going to do something, and using an instrument cable for a speaker lead increases the chance that this energy will do something bad.

[Walt-Dogg]

Ed, that's what I was getting at.

[EdBass]

Ed, that's what I was getting at.

My bad then Walt, I thought you said...

Just because it says on it that it is, does not mean it is functioning as one. In my experience this has happened to my Sunns from faulty cables connecting to the cabs causing current to draw back into the amp.

[Walt-Dogg]

Ed, that's what I was getting at.

My bad then Walt, I thought you said...

Just because it says on it that it is, does not mean it is functioning as one. In my experience this has happened to my Sunns from faulty cables connecting to the cabs causing current to draw back into the amp.

Ed I'm fairly certain you claim to know next to nothing about Sunn transitors amps but here you are posting in a thread about a Sunn transistor amps.

[EdBass]

Ed I'm fairly certain you claim to know next to nothing about Sunn transitors amps but here you are posting in a thread about a Sunn transistor amps.

That's right, I know almost nothing about about Sunn transistor amps; as compared to Sunn tube amps.
I also know a lot less about Sunn Hartzell and Fender era amps compared to Sunn Sundholm era amps.

I'm also not a degreed electrical engineer.

However, I do have a grasp on how transistors and transistor amps work.
Often people new to the Sunn world come to this forum for help with vintage Sunn gear. Just like jues did by starting this thread for example.
When erroneous or misleading information such as your "advice" to jues is posted specifically on a "help" thread it's counter productive to the original posters intent, e.g.; figuring out how to get their gear up and running. Also, we (mods and other members) often encourage new posters to use the search function to get answers from previous posts first.

This forum is smaller, slower, and less tolerant of bad technical information than some others are.
If erroneous, misleading, or "urban myth" type information is left standing unchallenged in a thread, it could be used as a "fact" in someone else's quest for answers about their Sunn gear, now or sometime in the future.


I suspect based on your history of similar situations over your "tech" posts over the years that you are looking for an argument Walt, but that still isn't going to happen, and again; as I have suggested to you in the past, I will suggest that you get a few basic electronics books by reputable authors and learn what you are talking about to support your "advice" before you start giving your technical advice to others about their gear issues.

Or, be prepared to have your wacky theories and myths challenged when you post them.


Now enough of the sideshow; that's that. Onward and upward to the situation jues has with his quiet Beta issue!

[Walt-Dogg]

Ed I'm fairly certain you claim to know next to nothing about Sunn transitors amps but here you are posting in a thread about a Sunn transistor amps.

That's right, I know almost nothing about about Sunn transistor amps; as compared to Sunn tube amps.
I also know a lot less about Sunn Hartzell and Fender era amps compared to Sunn Sundholm era amps.

I'm also not a degreed electrical engineer.

However, I do have a grasp on how transistors and transistor amps work.
Often people new to the Sunn world come to this forum for help with vintage Sunn gear. Just like jues did by starting this thread for example.
When erroneous or misleading information such as your "advice" to jues is posted specifically on a "help" thread it's counter productive to the original posters intent, e.g.; figuring out how to get their gear up and running. Also, we (mods and other members) often encourage new posters to use the search function to get answers from previous posts first.

This forum is smaller, slower, and less tolerant of bad technical information than some others are.
If erroneous, misleading, or "urban myth" type information is left standing unchallenged in a thread, it could be used as a "fact" in someone else's quest for answers about their Sunn gear, now or sometime in the future.


I suspect based on your history of similar situations over your "tech" posts over the years that you are looking for an argument Walt, but that still isn't going to happen, and again; as I have suggested to you in the past, I will suggest that you get a few basic electronics books by reputable authors and learn what you are talking about to support your "advice" before you start giving your technical advice to others about their gear issues.

Or, be prepared to have your wacky theories and myths challenged when you post them.


Now enough of the sideshow; that's that. Onward and upward to the situation jues has with his quiet Beta issue!

You were arguing with me about a speaker cable. You'd made me prove a point that you knew I couldn't articulate.

[jues]

ok if you would please put your ego aside?

okay. uhm i brought it to a guy in leipzig. he said it's kind of a transistor graveyard. output transistors and everything he said is broken he couldnt repair it so he's giving it to someone who actually has a bigger range of tools because he's in a workshop. and they even said that it could possibly happen that they cant repair it cause the amp is that old. and they said it will possibly be very expensive because they need to order some more new parts and some of 'em are very rare. they said it could possibly be over 100 € that would be like 130 dollar or more. i just hope they don't modify the sound of it.

and what i wanted to say is i'm getting a new volt converter if i get the other one back. i dont know if it was here on this forum but somebody told me that it isnt a good idea to run the 300watt beta lead on a volt converter that gives 300 watt at max. so i guess i need a bigger one. 500 watt or so, right?

[Oli]

Hi,

sorry, couldn`t get you on the PM side, so maybe this way:

I would ask here : http://www.silvermachine.de/, he is a great guy.

otherwise: Tubeampdoc in Worms, I got a nice guy here in Münster: Rareguitar.

The step down converter will not be your problem, if its running too "hot" the fuse will blow. It will not be that expencive as all parts are still on the market (see Conrad elektronik etc...), even a trannie is no problem.

Greetings from Münster,

Oli