Phono stage advice - diyAudio
Go Back   Home > Forums > Source & Line > Analogue Source

Analogue Source Turntables, Tonearms, Cartridges, Phono Stages, Tuners, Tape Recorders, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 11th November 2010, 01:04 PM   #1
diyAudio Member
 
Join Date: Feb 2006
Location: Ulverston in Cumbria
Default Phono stage advice

I want to run two turntables into one amp and the best way to do this would appear to be to run one straight into the amp phono input and the other via an external phono pre amp into a line input.
One T/T will be an old Dual unit for playing mainly 45’s and the other will be my “good” single speed T/T used for 33 only, both have MM cartridges at the moment. As I intend to upgrade to MC on the better T/T at a future date, the external MM phono stage seemed a good idea as I could upgrade to an external MC stage when required.

The amp is a Marantz PM66SE KI which I believe has a reasonable Phono stage anyway. Question is, can someone recommend a reasonable MM phono stage, self build, kit or ready to go, for use as an external unit. I don’t need anything esoteric so don’t want to spend the earth. The other question is, would I be better using the Marantz phono input for the better T/T?
  Reply With Quote
Old 11th November 2010, 05:21 PM   #2
diyAudio Member
 
Join Date: Jul 2010
Maybe an inexpensive DJ mixer would work.
You would end up with a single line level
output that would go into your non-phono
input on the main amp.
  Reply With Quote
Old 11th November 2010, 05:50 PM   #3
diyAudio Member
 
Join Date: Mar 2010
When I did that I built a switch box and that took care of it. Simply put two cartridge inputs to the switch and thence to the phono input. In many cases you don't even need a box, just hang it next to the receiver and velcro it.
  Reply With Quote
Old 11th November 2010, 07:18 PM   #4
diyAudio Member
 
Join Date: Feb 2006
Location: Ulverston in Cumbria
I had thought of a switch, I just had this feeling that I would get nods of disapproval for this as it could degrade the signal or introduce noise.
  Reply With Quote
Old 11th November 2010, 07:23 PM   #5
diyAudio Member
 
Frank Berry's Avatar
 
Join Date: Sep 2003
Location: Midland, Michigan
A magnetic phono level switch will create quite a "click" when you switch inputs.
Your idea of using an external phono preamp into a line input makes sense.
__________________
Frank
  Reply With Quote
Old 11th November 2010, 07:28 PM   #6
cr0wl3y is offline cr0wl3y  United Kingdom
diyAudio Member
 
Join Date: Sep 2009
Quote:
Originally Posted by davecooper View Post
I had thought of a switch, I just had this feeling that I would get nods of disapproval for this as it could degrade the signal or introduce noise.
Why would a switch introduce noise? Not being a smart *** here, genuinely interested to know if I'm missing something...
  Reply With Quote
Old 11th November 2010, 07:48 PM   #7
cr0wl3y is offline cr0wl3y  United Kingdom
diyAudio Member
 
Join Date: Sep 2009
Quote:
Originally Posted by Frank Berry View Post
A magnetic phono level switch will create quite a "click" when you switch inputs.
Your idea of using an external phono preamp into a line input makes sense.
That's true but can always take volume down or switch the amp input into something else during the time you switch. I'd definitely prefer to do that than compromise with a substandard phono stage or shelling out a couple hundred £/$ for a decent one.

Exception: given you want to try non-high output MC eventually, you could get a switchable MC/MM stage and skin both cats in one go.

I don't know what your amp phono stage sounds like, but I strongly advise against a cheap (<£/$100) DJ mixer, they really don't sound good. A second hand entry-level Graham Slee stage would be a better and not much more expensive option.
  Reply With Quote
Old 11th November 2010, 09:19 PM   #8
diyAudio Member
 
Join Date: Feb 2006
Location: Ulverston in Cumbria
Sorry, by noise I meant hum from unshielded connections. I would not have the amp selected to phono while I switched so no worried about switching noise.

I may initially get a good quality switch and build it into a shielded case with phono sockets. I will obviously have to get an external MC preamp when I get an MC cartridge. Do most MC pre amps have line level outputs or are they at MM levels for feeding into an MM input?
  Reply With Quote
Old 12th November 2010, 06:15 PM   #9
cr0wl3y is offline cr0wl3y  United Kingdom
diyAudio Member
 
Join Date: Sep 2009
You do not necessarily need a dedicated MC preamp, you can go down the passive route of using MC tansformers to bring the MC output to the required level. There are commercially available options or you could simply buy the transformers and put them in a suitable housing.

You can spend as little as £50-100 for a pair of "naked" second hand transformers on ebay or, for commercial products, anything between a couple of hundred to a couple of thousand quid, for the more esoteric or "trendy" stuff. Search for "MC transformer" under consumer electronics and you will see a wide range. Unfortunately I have never tried any of this at home so I cannot offer an opinion on what is good and what not.

RE shielding, you can use a metal housing or, if you want to make a pretty wooden box, foil the inside and connect it to ground and you should be fine. A nifty way to deal with both issues (selection and MC) would be to do everything in one box and either wire the transformers into one of the two inputs or "true-bypass" it with a 4pdt toggle switch before or after the input selector switch, for added flexibility.
  Reply With Quote
Old 13th November 2010, 05:10 PM   #10
diyAudio Member
 
Join Date: Feb 2006
Location: Ulverston in Cumbria
Thanks for the advice. Going to go with the switch box option until I can afford a reasonable MC cartridge and preamp.
I may build a two switch unit as my inputs are pretty full at the moment and I would like to add an MP3 device before too long.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Advice on hum in phono stage smbrown Tubes / Valves 2 4th November 2009 07:46 AM
DIY phono to replace roksan phono stage seroxatmad Analog Line Level 6 14th December 2008 06:46 PM
RIAA opamp phono stage advice mp741 Analogue Source 19 7th February 2006 09:49 PM
Should I replace Scott 222C phono stage with Claret phono stage? Bing Yang Analogue Source 0 22nd August 2005 07:41 AM


New To Site? Need Help?

All times are GMT. The time now is 09:26 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2