Sansui G 4700

resumedr

New Member
Hello to all Sansuiers,

I recently bought a Yamaha CR 700 on Ebay and what showed up was a Sansui G4700, not at all what I was expecting. I had been advised that Yamaha was what I wanted in a receiver or amp for the type of music I liked (classical). I hooked up the Sansui, and it was love at first hearing. Wow, was I impressed! The sound was warm and powerful, even with just 50 watts per channel. Well, I persevered and still got a Yamaha CA 610II amp and was expecting something even better than my Sansui. Was I disappointed in the Yammie! It was nothing compared to the Sansui. Herein, my problem I must have loved the Sansui to death because I proceeded to blow its two channels and fried it, as my audio repairman, a Yamaha man from way back, said to me. To quote him: "These electronics hate heat. It's OK to party for several hours but you must turn them off once in a while." I went ahead anyway and bought another Sansui G 4700. My question is: is he right (sounds reasonable to me) and the other thing did I do the right thing getting another Sansui G 4700?
Richard
 
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Some of the most important lessons in this hobby are learned the hard way. I once owned a G-5700 and wish I still did. It had the best sounding tuner I ever heard. Overall, the Sansui G-_700 series line is outstanding, although some will say the styling is a bit cheesy.
In your case, you already know the G-4700 is an excellent receiver but has longterm-use power limitations. Therefore, don't crank it "up to 11." If you are running a set of high-quality, efficient speakers, setting the volume at 5 or 6 should be plenty loud. With normal care, that unit should serve you well for years to come. :thmbsp:
 
Richard, that G-4700 can be fixed - I hope you didn't toss it out. :sigh: If you still have it, there's lots of folks here that can help guide you through the repair. Fix it and then keep it as a spare or sell it off. Their great little receivers! :yes:

Welcome to AK! :thmbsp: Make sure you introduce yourself in the Introductions Forum!
 
My first receiver I ever bought was a Sansui G-4700. I bought it on September 3, 1979. A date which, for me, will live in famy. (sorry for the bad joke, but my wife thinks I'm a bit nutty for remembering the specific date on which I bought something over 30 years ago).

I abused the heck out of that receiver. I bought it at the start of my senior year in high school, and it partied with me all the way through college. When I bought the receiver, I also bought a pair of Marantz HD-550 speakers. I liked them a lot. A nice, warm sound. If memory serves me correctly, they put out approximately 88 db at one watt. Not super efficient, but more than up to the task of sending out an invitation to the local police that I needed a reminder to turn it down.

Of course, then I had two sets of speakers hooked up to them (my college roommate had some cheesy kabuki speakers). A later roommate and I had my Marantzes teamed up with a pair of ARs, though I forget which model.

Always sounded great, though.

The best part about it? My oldest boy, who's now a senior in high school, has my G-4700 set up in his bedroom.

I always loved the looks of this receiver. It was really the first receiver that I'd ever seen that had digital displays or used LEDs for power meters. To me, that front panel, even though it's the smallest receiver in the family, looked massive, powerful. The big fluorescent tuner readouts are still bright and easily read from across the room. That beveled glass over the tuner display and the massive volume and tuner knobs impart more of that "big" look. Love the detents in the volume control, and really love how easily (still) the tuner dial spins.

Get that puppy fixed!!!
 
To add salt to the wound

Today the new replacement G4700 arrived. I, happily, hooked it up and for 5 (FIVE) minutes it played Verdi's Macbeth 2nd reel to reel, and I heard the most glorious sound I've ever heard from any source since I can remember, better than the previous G4700 that used to sit in the same place. And just as it started, the new G4700 died, deader than a door nail. Maybe it didn't like the trip over, USPS just 74 miles to here. Luckily the Ebay seller said he would pay for the repair, which is nice of him, isn't it? I think it may be a fuse issue. There was original product literature that came with the Owner's Manual about changing fuses in case the unit stopped working. So I am hoping that's it. Did the G4700 have an AM antenna? Anyway, I hope this unit is salvageable because I was wowed by those 5 minutes of music!
Richard
 
resumedr,
Your might want to check your speakers and wiring with a ohm meter since you have now two units down . The G-4700 does have fuses inside back by the transformer .

The G-4700 does not handle speaker loads of less then 4 ohms .


BTW what happened to the Yamaha CR ?


Barney
 
Barney,
The Yamaha CR 700 went to Canada instead where it was returned to the US as the Buyer refused delivery when he was warned of the switch. It's fine living in New Jersey, I suppose. If you were referring to the CA 610II, it's also fine waiting to be sold on Ebay, because I want my Sansui back!!!
Richard
 
In the accompanying literature there is a fold out 81/2 by 11 sheet with several items under the heading NOTICE. I think the first two may apply:
Quick-Acting Fuses:
When the indicator is glowing, if no sound comes out of one of more of the speaker systems, exmine their connections and operation once. If nothing is wrong with them, it is possible that the quick acting fuse or fuses protecting the power transistor have blown. (And then it explains to find blown fuses, discover the cause, and replace).

Power Fuse:
If the unit simply remains dead even after you have turned on its power switch, it is possible that its power fuse has blown. (And then it explains how to change.)

Let's hope that it is second! Will take a looksee.
Richard
 
G-4700 heat concern

If your G-4700 is in spec and running as designed, you should not have to shut it down for a cooling off period. There is adequate ventilation designed into the cabinet.

Heat is obviously an enemy of electronics, but more times than not people block ventilation by setting things on top of the receiver/amp or install the amp in a stereo cabinet that lacks good ventilation itself.

Again, if the amp section is running at spec. you shouldn't have to worry about the heat created by the output devices.
 
If your G-4700 is in spec and running as designed, you should not have to shut it down for a cooling off period. There is adequate ventilation designed into the cabinet.

Heat is obviously an enemy of electronics, but more times than not people block ventilation by setting things on top of the receiver/amp or install the amp in a stereo cabinet that lacks good ventilation itself.

Again, if the amp section is running at spec. you shouldn't have to worry about the heat created by the output devices.

Exactly, this will only be an issue if you are using it with more than one pair of speakers, or at sustained volume levels for which the G-4700 was never designed. If it is the latter, then you have the wrong model receiver for your listening requirements.
 
Having spent many hours completely refurbishing my G-4700, it isn't the heat in the outputs that will kill this receiver. In fact, if bias and offset are adjusted properly they will stay rather cool at low to moderate volumes. There is one transistor in the power supply which regulates the +46V to +12.5V, which gets EXTREMELY hot (180-200 degrees F). I tested another G-4700 while I had my hands on it briefly and it was the same. It will get so hot that it eventually unsolders itself. It also smells after a while. Sansui it seems tried to help by attaching another metal plate which dissipates the heat a little better. I cannot imagine how hot it got before the secondary bolted-on heatsink was added in production. I intend to soon test some modifications to the power supply section which I am hoping will make it run cooler, and I will probably try to post something about it if I have any success.

I will say that the G-4700 output section was only designed for loads of 8 ohms or more, so A+B at 8 ohms each will not work because then it sees a load of 4 ohms. That situation CAN heat your outputs up.

And yes I know this thread is old.
 
In regards to the discussion about the output rating on this receiver:

I'm looking around for an a G series Sansui. I stumbled upon a 4700 that I might buy. I have a pair of Klipsch RB-51 ii's (8 ohms) and I'm wondering about running those and another pair on the 4700 (want a second set of speakers with more bass). Can I run two sets of speakers on this receiver without too much risk of damage or overheating if both sets are efficient 8 ohm rated speakers? Confused.
 
I will say that the G-4700 output section was only designed for loads of 8 ohms or more, so A+B at 8 ohms each will not work because then it sees a load of 4 ohms. That situation CAN heat your outputs up.

And yes I know this thread is old.

The quote above is from the post above yours which I am surprised you did not see.

This is the answer to your question - a strong recommendation to run only 1 pair of speakers and ideally they should be 8Ω nominal impedance. Doing otherwise may result in overheating and possible amplifier failure.

Welcome to AK, and especially the "Exclusively Sansui" sub forum ! :)
 
Sorry, I don't mean to be redundant. I did indeed see the post above but I was still confused as to why the A+B setting would even be there if the receiver couldn't handle it and when Cwall99's post suggested that he was running 2 pairs on the 4700 and it survived to just fine to be passed down to his son.

Of course, then I had two sets of speakers hooked up to them (my college roommate had some cheesy kabuki speakers). A later roommate and I had my Marantzes teamed up with a pair of ARs, though I forget which model.

Are there suggestions on running two sets of speakers or is it still just suggested not to because of these over heating issues? Is this an issue on most of the Sansui receivers from the 70s and 80s?
 
I know, this thread is old, but I just ran into it while researching a G4700.

If you want to run two sets of speakers at once, get 16 ohm speakers. Or a different system. Frankly, I don't recommend running two sets of speakers at the same time on a receiver, but I suppose it couyld be done if the receiver supports 4 ohm speakers. I have never found a receiver that did. Perhaps the Pioneer SX1250 or 1980 would do it, but I wouldn't try it. That is power amp territory. Take a look at some high end power amps and even they tend to shy away from that. But the Yamaha M40 does support 2 or even 3 sets of speakers in the right configuration.

Choose the right system for your speakers or the right speakers for your amp, and don't over drive anything into distortion.
 
i am new and still trying to understand how this works. I just pick up a g 4700 and the right channel is not working. anyone out there that can guide me through a fix? I am a teaching myself how to repair and would love an help.. I did get a variac tool. I was told when receivers have been sitting a long time it is best to bring them up slowly
 
I couldn't help you with a real fix, but I will tell you you may wish to start by eliminating the possibility that dirty volume or balance control or selector switch is causing the problem. I have a good working G-4700 I picked up in a thrift store in 2008. The only problem it has had is recently I noticed I had to click the selector switch back and forth to get the left channel to play. It may be time for a De-Oxit treatment as detailed elsewhere on this site.



*edit* btw dquilci:

Good luck with your repair project and welcome to AudioKarma! You will probably have better response if you start a new thread for your repair project. Title it "Need Help Fixing G-4700 That Isn't Working on One Channel" or something like that. I have not been very active with the hobby and on this site the last few years, but always found a lot of helpful info an enjoyed reading about others' projects. There are a lot of helpful folks that are glad to share their expertise, but they may not see your request if it is tacked on the end of an older existing thread.

I hope I will read more about your G-4700 soon, I love mine!
 
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Hello, what a great resource; this site and thread! I'm a sansui lover, just discovered the 2 sets of speakers resulting in a recognized 4ohm situation??? I've been running 2 sets of jbl 4412 off my 8080 for years... I also run a auxillary fan behind the unit to help cool... the sound, besides being concert deafening at 8, is remarkable... question is ... am I inadvertantly damaging the unit by using the 2 sets? if so, then why does it have a combiner for A + B speakers???
thanks for your inputs..(good pun?)...Dave...
 
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