Help me with this simple question :)

[jmaster]

Hi Everyone , I had a question

I have an stereo amplifier , with 2 channels for Play , 2 channels for Phono1 and Phono2 , one channel for Tuner and one channel for AUX .

my two play channels are failed and i'm currently use the tuner channel for my cd player and everything is fine . I want to know that What's the difference between these channels (phono 1 , phono2 , tuner , aux ) and what is the usage of AUX channel ?

thanks so much

[Les Adams]

First of all I must confess I have no idea what "play" channels are and I have never come across them.

It is all to do with signal levels and impedance. Tuner, Line, CD and AUX inputs are designed to accept "LINE LEVEL" signals and are interchangeable - so plugging your CD player into a "Tuner" input will work fine,except that it is a little confusing when you are selecting which source you want to listen to!

A "PHONO" input is completely different. It is designed to accept and preamplify the very low voltage that comes from a pickup cartridge and should never have a line level device such as a CD player, tuner etc connected to it. At best the sound will be extremely distorted, at worst it will damage the built-in phono preamp. A PHONO input also applies an RIAA equalization curve to the signal. For a full understanding of exactly why this is necessary it is worth looking around the net. Some amplifiers have two different types of PHONO input, MM and MC for Moving Magnet and Moving coil cartridges respectively.

An "AUX" input is for connecting any additional line level equipment you may own such as a second CD player, Tuner, DAT machine (for playback only), DVD (audio) output etc etc...in fact pretty much anything audio, EXCEPT a record deck. A record deckis always connected to a PHONO input unless you are using an external phono stage / preamp in which case the output of such a device should be connected to a line level input such as AUX.

Hope that helps.

[JohnMichael]

Phono 1 and 2 are usually inputs for a turntable. The low output of a phono cartridge is further amplified and equalized for proper sound. A phono cartridge puts out a much lower voltage than a cd player or tuner. The extra amplification step brings it closer to the output levels of the other sources. Do not plug a cd player into a phono input as the output of the cdp would overload the phono section.

The other inputs are for any other component that does not require the extra step a phono signal will. It does not matter which inputs other than phono that you plug your cd player into since they are labled more as a convenience.

[Jimmy C]

...have an "equalizer" built in, an RIAA curve. Basically, to pick up the tiny signal from the cart and restore it to life.

Line levels (aux, tuner, CD, etc.) are the same.

I have no idea what "play" is, though!

[Jimmy C]

There was a delay on my answer being posted, didn't know the topic has been covered.

What is that "play", though?

[jmaster]

Thanks a lot guys , it helped a lot

Actually , my amp has two channels Labeled "Playback A" and "Playback B" , and has two channels that Labeled "Record A" and "Record B" .

[Corto Maltese]

Those are the TAPE inputs / LINE.

[Feanor]

Those are the TAPE inputs / LINE.

The two "Play" channels are for input from tape machines. These are usually activated by selecting "Tape Monitor" switches rather than the selector knob you use for CD, Tuner, etc.. In your case these tape monitors might be numbered "Tape 1" and "Tape 2".

Tape monitor inputs typically have impedance and sensitivity similar to the high-level inputs such CD. Hook something up to them, (e.g. CD player -- doesn't have to be a tape machine), then engage Tape 1 (or 2 whichever): you should hear sound. If not, you do indeed have a problem or some sort.

[jim goulding]

I don't know if this is universal, but I've read that using your tape input bypasses all the other circuitry of those other inputs giving you a more direct, purer feed from your CD player or DAC. I do this myself with my line stage and hear a reduction in harseness using my CD input.

[Mark of Cenla]

I don't know if this is universal, but I've read that using your tape input bypasses all the other circuitry of those other inputs giving you a more direct, purer feed from your CD player or DAC. I do this myself with my line stage and hear a reduction in harseness using my CD input.

That is quite interesting!

[Feanor]

I don't know if this is universal, but I've read that using your tape input bypasses all the other circuitry of those other inputs giving you a more direct, purer feed from your CD player or DAC. I do this myself with my line stage and hear a reduction in harseness using my CD input.

This isn't universally the case. In fact, more typically the Tape input gets the same treatment as other inputs such as CD, Aux, etc. What is pretty universal is the tape outputs bypass much of the processing; unfortunately this includes the volume control.

[jim goulding]

Yep. A review of my particuler line stage advised this but didn't say it was unique. I looked on the back panel and the tape input is separate from the line inputs. Looks that way under the hood, too.
Thanks, Fe.

[Feanor]

Yep. A review of my particuler line stage advised this but didn't say it was unique. I looked on the back panel and the tape input is separate from the line inputs. Looks that way under the hood, too.
Thanks, Fe.

The tape inputs won't be on the same selector spindle as the other because you have to be able to select the amongst stuff in order to tape it But check further downstream: usually the tape input path does lead to the tone control and, of course, the volume control circuits.

[PeruvianSkies]

I think you guys just saved someone from frying their stuff. lol.