Speaker level to line level question

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victoring

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I picked up a Panasonic RE7750A quad receiver in beautiful condition from a local thrift shop recently. It has no outputs other than 4 x RCA speaker jacks, rated 16ohms (along with a 2-channel tape output).

I have an Anthem AV40 preamp I'd like to connect it to.

I know I should probably buy inline attenuators to the tune of about 30db. However, my question is:

Could I instead just connect it to the 6-channel analog inputs (as I do with my other decoders and demodulators) and then adjust the internal input settings down by the right amount, or am I putting my other hardware at risk by doing so?

I've asked around and I'm getting mixed messages. Any help is appreciated.
 

Kal Rubinson

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Could I instead just connect it to the 6-channel analog inputs (as I do with my other decoders and demodulators) and then adjust the internal input settings down by the right amount, or am I putting my other hardware at risk by doing so?
You could but you would be skating on thin ice since the possibility (probability!) of damage to the Anthem will always be there. Why ask for trouble? Also, why are you doing it?
 

winopener

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Do you have soldering skills?
YES: get a line-out level from the Volume knob output
NO: Needs a high-power resistor.
 

victoring

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Do you have soldering skills?
YES: get a line-out level from the Volume knob output
NO: Needs a high-power resistor.
I know it's basic electronics but I don't really have the skill or experience. I don't mind buying something but all I can find are made for car audio hookups and have RCA on one end and speaker wire on the other. I see Harrison Labs sells inline attenuators but the highest level they sell is 12db. I'm thinking I would need two on each line which means I'm buying eight. I can't help but think there must be an easier way.
 

victoring

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You could but you would be skating on thin ice since the possibility (probability!) of damage to the Anthem will always be there. Why ask for trouble? Also, why are you doing it?
I have CD4 records and a compatible stylus but no demodulator, until now. I know there are others I could buy that do have line-out jacks but I'm trying to make what I have work. I'm sensing that in your opinion not such a great idea?
 

Soundfield

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I have CD4 records and a compatible stylus but no demodulator, until now. I know there are others I could buy that do have line-out jacks but I'm trying to make what I have work. I'm sensing that in your opinion not such a great idea?
I don't think the Panasonic RE7750A has a CD4 demodulator!
 

Kal Rubinson

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I have CD4 records and a compatible stylus but no demodulator, until now. I know there are others I could buy that do have line-out jacks but I'm trying to make what I have work. I'm sensing that in your opinion not such a great idea?
You can make it work but, imho, it requires either buying the speaker-to-line level adapters or building them.
 

victoring

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I don't think the Panasonic RE7750A has a CD4 demodulator!
If it doesn't, then there really is no point to connect this to anything. I swear I did research before I bought it. I seem to remember finding an old '70s ad from Panasonic that listed a CD-4 demodulator as a feature. I can't find it now which might mean I imagined it!

That being said, who wants to buy a Panasonic RE7750A in great condition? Includes four speakers!
 

par4ken

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I know it's basic electronics but I don't really have the skill or experience. I don't mind buying something but all I can find are made for car audio hookups and have RCA on one end and speaker wire on the other. I see Harrison Labs sells inline attenuators but the highest level they sell is 12db. I'm thinking I would need two on each line which means I'm buying eight. I can't help but think there must be an easier way.
The attenuators made for car stereo's that you are talking about will work fine.

I have CD4 records and a compatible stylus but no demodulator, until now. I know there are others I could buy that do have line-out jacks but I'm trying to make what I have work. I'm sensing that in your opinion not such a great idea?
Do I think that it's a great idea? Not really, an amp with line outputs would be better. The main problem with what you are proposing is you will be adding an unnecessary amplification stage that will add additional distortion,.
 
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Soundfield

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If it doesn't, then there really is no point to connect this to anything. I swear I did research before I bought it. I seem to remember finding an old '70s ad from Panasonic that listed a CD-4 demodulator as a feature. I can't find it now which might mean I imagined it!
Sorry to disappoint you, but if its the thing I just googled it isn't really quad of any description at all - it just has a four speaker imitation quad output.
pana.jpg

No decoders nor demodulators of any type! I think it's just basically a bedside radio!
 
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MidiMagic

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The car speaker attenuators will work fine - but only 4 are needed.

But they might not work with a Dynaquad type passive decoder because, unless they have transformers in them, they could short out the matrixing resistor on the ground side of the back speaker. This would give you two left channels and two right channels.
 
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