Back to my original question: balanced operation then is not possible using two amplifiers per channel (using bridged mode?)?
Yes, that is possible with most amplifiers.
But you need to take care not to overdrive the amplifier into low impedances since each amplifier sees effectively half the impedance of the load.
Also you need to drive the two amplifiers with out of phase signals, usually with an opamp front end added.
The benefit is almost 4 x the output power since it is a function of voltage squared.
The negative is alot of stress on the output stage if you use 4 Ohm loads or heaven forbid 2 Ohm loads.
I hope this helps
-Dan
Ballance or unballance input nothing have to do with bridged amplifier.
All the Public Adress and Studio equipments use the ballance technology to avoid noice(long wires between different equipments).
Most of home hi-fi use the unballance technology.
Ballance out-inp use 3 wires =
+inp,-inp,gnd.
Unballance out-inp use 2 wires=
+inp,gnd.
To drive an unballance input from a ballance output you need a ballance to unballance converter.
djhildreth is right keeping a bridged amplifier safe
Do you guys have a Power supply board that we can order? It might be a good addition to this project, so we can order all in one package. Just a suggestion.
The only thing I know is the Universal power supply. The board is too big, occupy too much space and more applicable to Class A amp. My point of having included on this project is to save time ordering board on another site and also save shipping cost. That's ok, if it won't be available. Thanks.
https://www.diyaudio.com/community/threads/peeceebee-psu-gb.320535/You can check this past GB, it is for claas AB with spk protect built-in, I think it is fine.
@ldarieut
I received a question regarding using the balanced output of a pre-amp to drive the Wolverine's single ended input.
I put this question to our small group and there was a few solutions put forward.
Here is one from @thimios , Thanks Thimios.
Below are a few options
The not expensive way
A more expensive option depending of the quality of the transformer.
For best results, use high quality transformers like Jensen, UTC, or even WE 111C (although they are huge) can be used. I have found several places where these transformers can be “scrounged,” DATS cards on the old 7300 series Scientific Atlanta satellite receivers, old modules from PRE consoles, etc. A simple audio “balun” can be constructed for little cost or effort and sound a whole lot better than doing it the wrong way.
I hope this helps you @ldarieut and other members.
I received a question regarding using the balanced output of a pre-amp to drive the Wolverine's single ended input.
I put this question to our small group and there was a few solutions put forward.
Here is one from @thimios , Thanks Thimios.
Below are a few options
The not expensive way
A more expensive option depending of the quality of the transformer.
For best results, use high quality transformers like Jensen, UTC, or even WE 111C (although they are huge) can be used. I have found several places where these transformers can be “scrounged,” DATS cards on the old 7300 series Scientific Atlanta satellite receivers, old modules from PRE consoles, etc. A simple audio “balun” can be constructed for little cost or effort and sound a whole lot better than doing it the wrong way.
I hope this helps you @ldarieut and other members.
Both of those examples connect audio ground directly to earth ground. Perfect way to make a humming mess out of a home audio system. If you are going to used balance connections in home audio where they are not meant to be used they need to be modified to let loop breakers and lifted grounds do their job.
Thanks Jeff, I will admit I don't know the finer details of converting a balanced output to single ended but, if this helps start a conversation that helps out @ldarieut then I don't mind posting.
Is it not possible that the images above just had the wrong ground symbol shown?
Or could the ground symbol just be removed and the ground reference taken from the lifted signal ground?
Pro audio with balanced connections uses earth ground for audio ground (so many different grounds!). If balanced is to be used for home audio it usually works best to connect pin 1 to chassis as pro audio does, then let the chassis loop breaker do it's thing and provide the ground reference.
THAT (1206) does an excellent solid state adapter to convert balanced to single ended but it too has the same problem with people connecting pin 1 to audio ground.
THAT (1206) does an excellent solid state adapter to convert balanced to single ended but it too has the same problem with people connecting pin 1 to audio ground.
Attachments
To allow balanced input you need to use an opamp with a circuit like I posted, or buy a balanced to unbalanced converter, or a high quality audio line level transformer (Jensen etc) and build it into your chassis. Most audio microphones run balanced (less noise etc) cabling, and you can quite simply tie the out-of-phase to gnd, and use the Hot as the drive. Or leave the out-of-phase disconnected, and simply use the hot and gnd.
Hi Jeff,i don't think so.
Both of those examples do not connect audio gnd to power gnd.
Gnd symbol is the signal gnd,not the power gnd.
I use the first one every day,no hum st all.
Pin 1 of an XLR connector is connected directly to chassis normally. More often than not this is actually done right in the connector itself through the mounting screw. As soon as you plug your XLR cable into your source you are connecting audio ground directly to earth ground in the source equipment if pin 1 is connected to audio ground in the amplifier.
You are right!
The XLR pin 1 connection conflict!
In any case,do not expect any hum as soon as power gnd not connected at both end.