Sansui and 4 ohm

usedto

Lunatic Member
My son just picked up a pair of Klipsch KG2s that I want for a system for my 8' X 20' portable office. I plan on running my computer and TV through the system, as well as using the tuner.

The speakers are 4 ohm - 65w rating. All of my other Sansuis are a little too nice for my dirty office, so I plan on picking up a receiver just for this purpose. Are there any that will have a problem with the 4 ohm load, or any that would be best?

Thanks
 
I blew an output transistor on an AU 7700 because I ran 4 ohm speakers for a short time with it (according to the tech 37 years ago). (It was repaired under warranty) I have avoided 4 ohm speakers since then.
 
I've got 4 ohm speakers hooked up to every one of my Sansui receivers. I've never had an issue. It's when you hook up four speakers that are rated 4 ohm is when you start to run into troubles.
 
I've got 4 ohm speakers hooked up to every one of my Sansui receivers. I've never had an issue. It's when you hook up four speakers that are rated 4 ohm is when you start to run into troubles.

That doesn't make sense. I think that at low power (volume) levels it will not be a problem, but at the limit when you are trying to drive 4 ohm speakers with an amp designed for an 8 ohm speaker a 4 ohm speaker will try to draw more amps. If the output transistors aren't designed for the higher amperage draw you have problems. But, what do I know.
 
I have a pair of 50-60w 4ohm speakers connected to my AU-719 as secondary (B) speakers. Usually use them at late hours or outside on the porch during the summer, have not done anything to my amp other than sounding sweet.
 
That doesn't make sense. I think that at low power (volume) levels it will not be a problem, but at the limit when you are trying to drive 4 ohm speakers with an amp designed for an 8 ohm speaker a 4 ohm speaker will try to draw more amps. If the output transistors aren't designed for the higher amperage draw you have problems. But, what do I know.

I meant when you have 4 ohm speakers hooked up to A and B and you're driving them all at the same time. With the way some receivers are wired, it will present the amp with a 2 ohm load. That is when you will run into problems.
 
I meant when you have 4 ohm speakers hooked up to A and B and you're driving them all at the same time. With the way some receivers are wired, it will present the amp with a 2 ohm load. That is when you will run into problems.

Ok, but obviously you know that 4 ohm, 8 ohm amp means nothing. It is what the power supply provides voltage wise and what the amp output transistors are designed to handle handle current-wise. A designer figures that an amp will be used at full volume some percent of the time and designs a power supply supplying voltage and output transistors that will handle current into an 8 ohm load. Obviously, if a 4 ohm load is presented, more current will be drawn and at high volume for a long time, could cause problems. At least, that's how I understand it.
 
The 8080DB will have no problem with 4 ohms. If you want a G series receiver stay with the G-x000. The later G-xx00 series are not as robust. If you want extra protection, swap out the output transistors for on-semi MJ21193/4. They are more robust than anything Sansui used. (Be sure to save the originals.)

- Pete
 
The 8080DB will have no problem with 4 ohms. If you want a G series receiver stay with the G-x000. The later G-xx00 series are not as robust. If you want extra protection, swap out the output transistors for on-semi MJ21193/4. They are more robust than anything Sansui used. (Be sure to save the originals.)

- Pete
The AR3as and Sansui 8080. Good combo?
 
I avoid four ohm loads with Sansui. Just not a good mix. They may sound ok, but the speakers will sound much better with an amp that is designed to drive four ohm loads.
 
There is no problem at all running one pair of properly working 4 ohm on a properly working 8080. Just don't run two pair.

- Pete
 
That doesn't make sense. I think that at low power (volume) levels it will not be a problem, but at the limit when you are trying to drive 4 ohm speakers with an amp designed for an 8 ohm speaker a 4 ohm speaker will try to draw more amps. If the output transistors aren't designed for the higher amperage draw you have problems. But, what do I know.

His comment made perfect sense, at least to me.

Also, note that at any given volume (voltage), a speaker with an impedance of 4 ohms will draw more current than one with an impedance of 8 ohms. In other words, this is the case at all output levels...not just when "at the limit" (by which I assume you meant running the amp at a very high output level).
 
The output transistors in an 8080 are robust enough for a 4 ohm load. The amp will clip and potentially damage your speakers well before the outputs fail.

- Pete
 
I am driving a pair of MB Quarts "Quart Two" speakers with Sansui 310 (14 WPC) ol' receiver. No issues so far....! and sounds great too.
 
Back
Top Bottom