Phono-Input Switch - Multiple TTs

[Record Player]

Many of us have multiple turntables or even multiple tonearms on a single TT, however this can be a hassle when it comes to Phono Stages.

A Phono Input Switch Box would be perfect. I've seen a few of these in the international market. Does anybody have something like this in their setups. Any working knowledge on this. Do you think such a switch will have any loss of fidelity?

I am seriously contemplating one of these for my turntables.

BTW, how do you guys currently manage with multiple turntables and one phono stage?

Looking forward to your thoughts.

 

[kuruvilajacob]

Sohail,
There are several integrated amps like Kenwood KR 7600 and Sansui QR 4500 with two separate MM phono inputs. I also use the phono stage of good integrated NAD amps by connecting the TT to the phono and taking an out connection through record out to main amplifier. This is my way of connecting multiple TTs

 

[greenhorn]

I use one of these to manage my cassette decks (got a whole bunch of them), and don't want to wear out my vintage amp's source selector
3 Port Audio Video AV RCA Switch Switcher Selector BOX Splitter FOR HDTV Cable | eBay

 

[reignofchaos]

Not a good idea unless you know what you are doing. The biggest issue is that the output voltage is is just a few millivolts or less than a millivolt in case of mc carts and any connectors in the path if done poorly will cause significant signal deterioration.

This is the same reason why most tone arms come with captive leads instead of rca connectors.

 

[hildebrand]

I have a related question.
Many of the amps will have multiple inputs. Mine has AUX, CD and DVD.
Someone had suggested to give pre-amp output from phono stage to AUX only. What is the sanctity of that? Can we connect to any input as it is claimed that the output of phono stage/pre-amp is line level?

 

[reubensm]

I have a related question.
Many of the amps will have multiple inputs. Mine has AUX, CD and DVD.
Someone had suggested to give pre-amp output from phono stage to AUX only. What is the sanctity of that? Can we connect to any input as it is claimed that the output of phono stage/pre-amp is line level?

Yes it will work.

Tape, Aux, CD, Video/DVD and Tuner inputs are kind of similar from a impedance and balancing perspective. However you may notice minor variances in the gain of these inputs as they may have been specifically designed for the intended source. For example the output of your cd player would be much higher than your phonostage or tuner. The designated inputs would ideally compensate for this.

 

[reubensm]

Not a good idea unless you know what you are doing. The biggest issue is that the output voltage is is just a few millivolts or less than a millivolt in case of mc carts and any connectors in the path if done poorly will cause significant signal deterioration.

This is the same reason why most tone arms come with captive leads instead of rca connectors.

I second this opinion as its never a good idea to put switching in between your cartridge and the phonostage. The better option would be to use 2 phonostages and have the outputs connected to different inputs on the amp. I have used upto 3 turntables on a single amp, with one connected via the in-built phonostage, one running through an external phonostage to the Aux input and the third one running through an external phonostage to the Video input (of my 106 preamp). Worked well.

 

[reubensm]

Your 306 has 2 phono inputs (if I remember correctly, one is for MM and the other can be switched between MM and MC), hence you can connect upto 2 TTs to this amp

 

[stillsearching..]

(Multiple turntables into one phono stage - AudioAficionado.org) been looking for an answer for a long time.was about to buy another phono preamp..

 

[reubensm]

(Multiple turntables into one phono stage - AudioAficionado.org) been looking for an answer for a long time.was about to buy another phono preamp..

great idea but those switches have to be of the highest possible quality.

 

[jls001]

Use two phono stages. It is the more practical solution, especially if you use MCs that may have different gains and loadings. Unless one has a very flexible phono stage that allows changing the settings without a major operation like opening the top plate to reach DIP switches, multiple phonos is more sensible.

 

[hildebrand]

Yes it will work.

Tape, Aux, CD, Video/DVD and Tuner inputs are kind of similar from a impedance and balancing perspective. However you may notice minor variances in the gain of these inputs as they may have been specifically designed for the intended source. For example the output of your cd player would be much higher than your phonostage or tuner. The designated inputs would ideally compensate for this.

I thought so too that gain maybe different.

 

[reubensm]

I thought so too that gain maybe different.

yes, input sensitivity

 

[kuruvilajacob]

Just like speaker amp matching, phono stage cartridge matching is very important for getting the best out of the system. But it may not work as per the books. It is all personal liking. I have a phono stage made by a friend for which I fixed an external transformer which took care of some earlier hum noise. It sounds much better to my ears while using all Shure carts . Some old Japanese amps have a much better sounding phono stage than many stand alone phono stages . Now to the topic we are discussing, separate inputs are much better than changing , as many a time, RCA inputs tend to get damaged when pulling in and out several times.

 

[Record Player]

Great inputs gents. Of the reviews I read of this type of a switch, there will be loss in quality production unless its made very accurately and with very high quality components but there will still be loss.

Using multiple phono stages will be the best option.

Cheers...

 

[Record Player]

Your 306 has 2 phono inputs (if I remember correctly, one is for MM and the other can be switched between MM and MC), hence you can connect upto 2 TTs to this amp

Yes Reuben, the 306 has 2 phono inputs. One for MM and the other for MC. Now my second TT has an MM cart as well and connecting this to the MC Phono Input does not help. Any ways around this to make this sound just like an MM cart using this MC input?

 

[reubensm]

Yes Reuben, the 306 has 2 phono inputs. One for MM and the other for MC. Now my second TT has an MM cart as well and connecting this to the MC Phono Input does not help. Any ways around this to make this sound just like an MM cart using this MC input?

I have tried out using a MM cart through my preamp switched in MC mode. It sounded too loud and harsh and hence I reverted back to the MM mode. There are multiple factors behind this but I must say that it sounded awful to my ears.

 

[Record Player]

I have tried out using a MM cart through my preamp switched in MC mode. It sounded too loud and harsh and hence I reverted back to the MM mode. There are multiple factors behind this but I must say that it sounded awful to my ears.

Absolutely, that's how it sounded to me as well! I guess there is no way around this unless I get me self an MC Cart.

Do you think using an elchepo phono preamp and connecting it to the 306 Aux Input will help?

 

[jls001]

Average MM phono stage gain = 40 dB
Average MC phono stage gain = 55 dB, at least. Most are higher than 55 dB, typically 60-62 dB, and some are as high as 70 dB.

Impedance loading for MM cartridges = 47 kOhms
Impedance loading for MC cartridges = 100 Ohms, typical

Capacitive loading for MM cartridges = 100 to 300 pF, typically. This figure is irrelevant for MCs.

There is no easy way to make an MC phono pre suitable for an MM. One can probably "step down" the gain by introducing a resistor of appropriate value in series, but one needs to still take care of the resistive and capacitive loading too.

Bottomline: don't do it

 

[reubensm]

Absolutely, that's how it sounded to me as well! I guess there is no way around this unless I get me self an MC Cart.

Do you think using an elchepo phono preamp and connecting it to the 306 Aux Input will help?

If you are using MM, they why not try to use a Nad phonostage? The PP series Nad phonostages work very well with Nad amps. Having said that, there is no harm in trying other stages as well. The ideal solution for you would have been to use a NAD 1020 preamplifier (My father had this one and we sold it off a few years ago, if I had it I would have given it to you). However by present rates, that is going to be an expensive proposition. Why not try the CNC?