Speaker wiring on amp 182

[Hydrolastic]

Hello, One issue with the Continental is the horns do not work on either channel. I was going to remove it and bring it to Sam at sound audio. Then thought about it and this is probably a good thing to try and look at myself since i know that Sam has replaced all of the capacitors and tested the tubes. He told me he had it playing in the shop so he must have hooked it up to a set of speakers and for sure it would be a 2 wire setup. Now that i have it home and on its original 3 wire speaker system one of the wires is dead on both channels. This means i would do my first capacitor discharge and if the wiring is correct i would need to power it up and trace channel output. By the way i already substituted the extra horns i had to see if the diaphrams were corroded but it was exactly the same. Anything i need to know and or what minimum of test equipment do i need ? Hydro

[electra225]

Is there a sticker pasted in the cabinet that gives the speaker wiring layout? My guess is that something is miswired.

[Moto_TJ]

Did they work when you got the amp back and they stopped, or did they never work after getting it back?

I know some amp guys like to convert these from bi-amps to regular amps. I have a 182 on the shelf, I will get some pictures this evening, hopefully, and hopefully help figure out your issue!

[Hydrolastic]

Hello Moto. As far as the amp 182 and the horns working i never fired it up before it went to be recapped as i was told it didn't work when i got it. Not sure what Biamped is so i can't comment on that. When i got the amp back i installed it and put the cabinet speaker wires back on. (From photo's) I did remove the external switches and all the crappy wiring that i think controlled other rooms but the three wires from the amp chassis to the front speaker. The horns never operated. during thee first run while on the crossed tape "in" and "out" there was a rumble from channel 2 but now that i am on the phono inputs its gone. There is the original switch that i now can use and it switches the speaker from int, ext and both. The int and Both are swapped so it doesn't match the bezel.
I got a Sams from steves and had it printed out on 11" x !7" paper so i could read it. I realized that the Sams doesn't have color codes for the wires like a car would have so i am going to have to trace them out individually. I think that there are a couple of options here... Sound audio connected the 3 wire into a two wire setup. Or something in the external wiring switch for the extra rooms has them disconnected. Either way i am going to have to trace the wires. At one point i had the bluetooth on the phono jacks and just the woofers operating and i clearly heard it go into stereo. I wonder how many decades have gone by side it last did that! I am hoping it is going to sound as good as my 1st208 concert hall when its finally going right again. I would like to get an evening this week to work on it. Hydro

[electra225]

The term "bi-amps" refers to Magnavox's split-frequency amplifiers. You actually have four separate amplifiers built into one chassis. You have two for the treble amp, one for each channel and two for the bass amp, one for each channel. You may have already told us, but have you checked to see if the horns work at all? I believe the audio goes thru the Molex connector plug to the external speaker switch, then on to the speakers from there. Do you have access to a signal tracer? That might be the best and easiest way to determine if you still have bi-amps or if someone has wired them to a traditional stereo amp.

[Hydrolastic]

Thank you Greg for explaining that to me. I got the SAMS out and i carefully removed the amp and i got it up on its side so i could look underneath it. I used the diagram in the SAMS to make sure each wire was on the pin that it should be. By numbering the switch terminals and the plug and the switch, I was able to determine that all was right with that part of the wiring. But one interesting thing is the description in the manual.... well i will let the photo of it tell the story. Basically the bezel is different than the description. More on the next posting. Hydro

[Hydrolastic]

Hello, This next thing i did so i could put the speaker leads on and off while the unit was on i was very careful around the unit while it was on not to disturb the amp at all. If i swapped the two L leads onto the High speaker the horns (individually) will work . Then i noticed the three pots on the deck of the amp (bass channel 2) (treble 1)(Treble 2) i turned these all to maximum the sound did not improve in quality or volume. At least the treble. The bass channel 2 has a notch up in volume in both interior and exterior speakers on the exterior speaker it will go down to 0 with the channel 2 pot but the interior it only turns it down about 50 percent. the two treble post do nothing. It's all pretty wonky. I did verify the H and L wires are correct on each channel . I still think this is an internal problem in the amp. I think i am going to take it back to Sam with the speakers so he can see the three wire setup.

[Hydrolastic]

Hello Guys, As i posted else where the Continental is fixed and the issue was a tube a 12ax7 i believe. I was perplexed with the 3 pots (only 3) and what they did. Ch2 bass ch 1 treble ch2 treble. Sam explained that channel 1 bass is the standard and that you set the 3 channel pots to match channel 1 bass. So now that we know this i was wondering if there was a procedure for this or if its just by ear. It seems you also have a range on the preamp bass, treble knobs? Also as per Hifi mogul i am borrowing a oscilloscope from a freind and will see what kind of signal is coming out and what adjustments i can set it to. Hydro

[electra225]

The instructions for setting balance on the 88 and 93 series amp is to use a mono signal, connect an AC voltage meter to speakers in each channel, the set balance until the voltages are equal. I haven't seen any such instructions for the bi-amps, but I don't see why that wouldn't work for bi-amps. Set the bass channels first, then the treble. Use a mono signal to set them alike. The 81 and 82 series bi-amps don't have any bass controls like the earlier ones did. I don't believe anybody fully understands the tone controls on a Magnavox bi-amp.