Does anyone else like FM?

[Mark1]

They're designed for different load impedances (and different sensitivity/voltage). Depending on the load, it can make little difference or quite a bit of difference. Often, (indeed, typically), driving a line-level input from a headphone output is workable.

I wasn't sure what the output impedance and voltage on a headphone output jack typical or specifically is. It's the one spec that's not publish on my receiver for instance. I sort of assume it might be similar to a receiver's other audio outputs assuming it has any, but was doubtful since the phone output is for a different purpose powering tiny speakers. That's why I like to use audio outs intended to go to a preamp or amp and know what their specs are and even use matching brands lol.

 

[Doodski]

I wasn't sure what the output impedance and voltage on a headphone output jack typical or specifically is. It's the one spec that's not publish on my receiver for instance.

A general rule of thumb for receivers without a dedicated headphone amp built in is about 200 to about 400 Ohms output impedance. If you give me your receiver model and make I might be able to look up a schematic.

I sort of assume it might be similar to a receiver's other audio outputs

RCA outputs are much lower impedance than a headphone output.

use matching brands

Not required. Mixing and matching can be good too.

 

[Mark1]

A general rule of thumb for receivers without a dedicated headphone amp built in is about 200 to about 400 Ohms output impedance. If you give me your receiver model and make I might be able to look up a schematic.

RCA outputs are much lower impedance than a headphone output.

Not required. Mixing and matching can be good too.

That is much lower than RCA outputs. I think my receiver RCA outputs are like 10 kOhm. To be honest I'm not really sure what all the ramifications would be using headphone ~300 ohm output impedance vs `10 kOhm for volume control, distortion and sound quality but imagine it wouldn't be ideal .

I know mix and matching can be good, but keeping it all make and model matched usually not always makes it easier to get a good match.

 

[Doodski]

That is much lower than RCA outputs. I think my receiver RCA outputs are like 10 kOhm. To be honest I'm not really sure what all the ramifications would be using headphone ~300 ohm output impedance vs `10 kOhm for volume control, distortion and sound quality but imagine it wouldn't be ideal .

I know mix and matching can be good, but keeping it all make and model matched usually not always makes it easier to get a good match.

What receiver do you have?

 

[Blumlein 88]

That is much lower than RCA outputs. I think my receiver RCA outputs are like 10 kOhm. To be honest I'm not really sure what all the ramifications would be using headphone ~300 ohm output impedance vs `10 kOhm for volume control, distortion and sound quality but imagine it wouldn't be ideal .

I know mix and matching can be good, but keeping it all make and model matched usually not always makes it easier to get a good match.

Some confusion here. Your receiver RCA out jacks don't have 10 kohm output impedance or none I've ever heard of did so. As already described it was quite common for old receivers to tap the amplifier output and run it thru 470 ohms to lower the output level. That is a rather high output impedance for phones, but not a big deal with phones way back when.

 

[EJ3]

They're designed for different load impedances (and different sensitivity/voltage). Depending on the load, it can make little difference or quite a bit of difference. Often, (indeed, typically), driving a line-level input from a headphone output is workable.

I have only heard of it not working. But every one that I have ever tried it with (from the late 1970's to now, has worked as if it were the same as RCA's. (and in most things, I have been able to directly compare it to the RCA's on the same device. (I will say: That is to my ears, at least). But I have not ever had anyone say: "that doesn't sound right, what's wrong with it"???

 

[EJ3]

What receiver do you have?

I think that this is what @Mark1 has:

 

[Doodski]

I think that this is what @Mark1 has:

Headphone output is 680 Ohms as can be seen by the orange square around the resisters.

 

[DanielT]

I got inspiration from this thread. Thus, an antenna cable from my receiver went out to the balcony. Excellent reception. So far all good.

Then listen to FM radio. Then it wasn't so much fun anymore. More advertising than ever. Okay, I can listen to some talk radio and news, but beyond that, well, ...nop...Why FM radio considering all these internet radio stations that exist nowadays that you can choose instead? Example:

 

[EJ3]

Headphone output is 680 Ohms as can be seen by the orange square around the resisters.
View attachment 427721
View attachment 427722

@Doodski: I think that he is wanting to do what I am doing: running the headphone output of a Sony XDR-S3HD into one of the inputs of his Sony receiver.
I am running my Sony XDR-S3HD headphone output (3.5 MM) through a Y connector to RCA stereo into my Apt/Holman preamp.
I think that he is wondering if that would be OK with one of the inputs on his receiver or if their would be some mismatch impedance issues that would screw up being able to do that. (I can only say that it has worked for me [I did not check anything, I just tried it {from here say} and it worked).

 

[Doodski]

@Doodski: I think that he is wanting to do what I am doing: running the headphone output of a Sony XDR-S3HD into one of the inputs of his Sony receiver.
I am running my Sony XDR-S3HD headphone output (3.5 MM) through a Y connector to RCA stereo into my Apt/Holman preamp.
I think that he is wondering if that would be OK with one of the inputs on his receiver or if their would be some mismatch impedance issues that would screw up being able to do that. (I can only say that it has worked for me [I did not check anything, I just tried it {from here say} and it worked).

Yes, and the source output impedance will be 100 Ohms.

 

[mhardy6647]

It'll work -- and it'll do no harm.

 

[EJ3]

It'll work -- and it'll do no harm.

I've done this kind of thing with with various gear since the late 1970's (usually a temporary thing, just to check if something was working (& if it did [which it always did] it might get left that way for a week or 2] {but, of course, this is a permanent situation, so I can see where some would want assurances of it being a "no harm" situation}). I have been doing it for a couple of years with my Sony XDR-S3HD headphone output (3.5 MM) through a Y connector to RCA stereo into my Apt/Holman preamp and it has always worked for me when I have done it, even with computers as the source.
So, their you go, folks that wonder about this, it's fine.

 

[EJ3]

I got inspiration from this thread. Thus, an antenna cable from my receiver went out to the balcony. Excellent reception. So far all good.
View attachment 427733View attachment 427734View attachment 427735View attachment 427736
Then listen to FM radio. Then it wasn't so much fun anymore. More advertising than ever. Okay, I can listen to some talk radio and news, but beyond that, well, ...nop...Why FM radio considering all these internet radio stations that exist nowadays that you can choose instead? Example:
View attachment 427737

Because in some areas you don't get a cell phone signal to to stream from but you CAN get 45 FM stations ([not fringe, no Dxing needed] {and Dxing for more is fun} at least where I am with an over the air FM antenna) and 36 TV stations with an over the air antenna UHF/VHF, mounted on the chimney.
And, naturally, since most of the FM stations aren't oriented to big cities (and don't have [big cooperate overlords]), you get a lot of locally liked music, locally oriented news & event coverage & less commercials.
A lot like FM was prior to the late 1980's.
Not many car salesmen or lawyers screaming over the radio.

 

[Mark1]

What receiver do you have?

https://www.sony.com/electronics/support/res/manuals/W001/W0010546M.pdf

Headphone output is 680 Ohms as can be seen by the orange square around the resisters.
View attachment 427721
View attachment 427722

Yep that's spec sheet for the receiver I'm using. How did you get the schematic? Maybe if we had the schematic of the tuner section someone could tell if it has a post detection filter or some filtering for HD self-noise and also what kind of demodulator it has PLL or what .

Some confusion here. Your receiver RCA out jacks don't have 10 kohm output impedance or none I've ever heard of did so. As already described it was quite common for old receivers to tap the amplifier output and run it thru 470 ohms to lower the output level. That is a rather high output impedance for phones, but not a big deal with phones way back when.

Doodski found the phones output of 680 Ohms which agrees with what you're mentioned and kind of high but makes sense since it is 100W/channel amp. Which, not to question at all EJ3 that it will sound and work fine, points out another reason I'd rather not use phone out jack to preamp input of my receiver since it has gone through a power amp and not as clean. I'm just a stickler about not doing that even if I couldn't really hear the added distortion . Anyway, so is not my RCA outputs 10 kiloohms as the specs sheet suggests? Is that high for RCA outputs?

 

[Mark1]

@Doodski: I think that he is wanting to do what I am doing: running the headphone output of a Sony XDR-S3HD into one of the inputs of his Sony receiver.
I am running my Sony XDR-S3HD headphone output (3.5 MM) through a Y connector to RCA stereo into my Apt/Holman preamp.
I think that he is wondering if that would be OK with one of the inputs on his receiver or if their would be some mismatch impedance issues that would screw up being able to do that. (I can only say that it has worked for me [I did not check anything, I just tried it {from here say} and it worked).

Yes, and the source output impedance will be 100 Ohms.
View attachment 427752

It'll work -- and it'll do no harm.

I'm probably too hard headed to connect phone jack to receiver audio input . I am curious though about impedance matching, volume control and distortion . With the Sony radio phone out low impedance wouldn't one have to turn the radio volume low and the receiver volume high for lower distortion? Then I see how high the receiver's input impedance and wonder if the low impedance of the phones matters. I'm curious just what the voltage and THD is out of the phone jack. There's got to be some good reason why preamp/line level audio out jacks have high impedance. I'm not clear what it is but I want to have it

 

[Mark1]

I've done this kind of thing with with various gear since the late 1970's (usually a temporary thing, just to check if something was working (& if it did [which it always did] it might get left that way for a week or 2] {but, of course, this is a permanent situation, so I can see where some would want assurances of it being a "no harm" situation}). I have been doing it for a couple of years with my Sony XDR-S3HD headphone output (3.5 MM) through a Y connector to RCA stereo into my Apt/Holman preamp and it has always worked for me when I have done it, even with computers as the source.
So, their you go, folks that wonder about this, it's fine.

I believe you it will work and probably even sound transparent and I'd do it in a pinch. But this one area I turn into an audiophool and want the minimum of circuitry and only one preamp and power amp in the signal path and all the voltage, sensitivities and impedance to "match". Although I am curious and could be convinced none of that matters, actually I pretty sure already it probably doesn't for FM, but still lol.

 

[mhardy6647]

It is trivial.
Get one of these:

Random internet image -- you can get such a gizmo from Amazon or... pretty much anyplace that sells electronic gee-gaws and gimcrack.
Here's a not entirely random example from that rainforest-themed company:

https://www.amazon.com/Amazon-Basics-Adapter-Subwoofer-Gold-Plated/dp/B01D5H8JW0/ref=sr_1_3

You have (i.e., you will have) two volume controls you can adjust -- the one on the HD radio, and the one on your receiver. Try 'em both. Don't start with the output of the radio too high, but don't hesitate to turn it up if you need more signal in to your Sony receiver. I won't say you can't do any harm... but I will say that you'll have to work at it to do any harm!

 

[Mark1]

Because in some areas you don't get a cell phone signal to to stream from but you CAN get 45 FM stations ([not fringe, no Dxing needed] {and Dxing for more is fun} at least where I am with an over the air FM antenna) and 36 TV stations with an over the air antenna UHF/VHF, mounted on the chimney.
And, naturally, since most of the FM stations aren't oriented to big cities (and don't have [big cooperate overlords]), you get a lot of locally liked music, locally oriented news & event coverage & less commercials.
A lot like FM was prior to the late 1980's.
Not many car salesmen or lawyers screaming over the radio.

And in my/our area analog FM sounds better to me than online FM stations. Luckily, surprisingly for being in a rather large city I don't have too many commercials on my local FM stations.

 

[Mark1]

It is trivial.
Get one of these:

View attachment 427836
Random internet image -- you can get such a gizmo from Amazon or... pretty much anyplace that sells electronic gee-gaws and gimcrack.
Here's a not entirely random example from that rainforest-themed company:

https://www.amazon.com/Amazon-Basics-Adapter-Subwoofer-Gold-Plated/dp/B01D5H8JW0/ref=sr_1_3

You have (i.e., you will have) two volume controls you can adjust -- the one on the HD radio, and the one on your receiver. Try 'em both. Don't start with the output of the radio too high, but don't hesitate to turn it up if you need more signal in to your Sony receiver. I won't say you can't do any harm... but I will say that you'll have to work at it to do any harm!

That gave me an idea. Similarly I didn't want to use speaker level inputs for my JBL powered subwoofer as the receiver has no sub out and trying the line level outs didn't work good. But what if I used that connecter from the phones to the subwoofer preamp input it might be simpler and sound better than speaker level input.


In contrast this Yamaha RN600 line out and headphone output voltage and impedance are practically the same https://manual.yamaha.com/av/22/rn600a/en-US/9938559755.html

Rated Output Voltage / Output Impedance (CD etc. Input 1 kHz, 200 mV)
LINE OUT	200 mV/1.0 kΩ
SUBWOOFER OUT (30 Hz)	4.0 Vrms/1.2 kΩ

Headphone Jack Rated Output Power (1 kHz, 200 mV, 8 Ω load)

410 mV/470 Ω

I don't understand how if my Sony receiver's input impedance is 50 kiloohms you get any volume or voltage using either a phono or line level feed, or why the Sony receiver's output impedance is listed at a high 10 kiloohms, but I guess it all works somehow.