Has anyone used a speaker level to line level converter?

Discussion in 'AV Receivers' started by EdNichols, Apr 23, 2003.

  1. EdNichols

    EdNichols Second Unit

    Joined:
    Feb 15, 2003
    Messages:
    372
    Likes Received:
    0
    I have an Onkyo receiver with no pre-outs and I would like to eventually upgrade to separates but can't swing the pre/pro thing right now. I want to get the amp first and wondered if anyone has used a converter. If so, what kind of results did you have and if you eventually went to a full pre/pro later on could you tell a big difference between it and using the converter?
     
  2. Craig_Kg

    Craig_Kg Supporting Actor

    Joined:
    Feb 25, 2002
    Messages:
    768
    Likes Received:
    0
    Yep - made them myself.
     
  3. EdNichols

    EdNichols Second Unit

    Joined:
    Feb 15, 2003
    Messages:
    372
    Likes Received:
    0
    What kind of results did you get?
     
  4. Jassen M. West

    Jassen M. West Supporting Actor

    Joined:
    Jun 22, 2000
    Messages:
    526
    Likes Received:
    0
    could you post how you made them? materials maybe a step by step?

    thanks
     
  5. Andrew Pratt

    Andrew Pratt Producer

    Joined:
    Dec 8, 1998
    Messages:
    3,806
    Likes Received:
    0
    I still wonder about the benefits of doing this since any distortion that the onboard amps will still be there in the line level signal which you'll then amplify with the power amp again so I'm not sure it would be worth the effort. As they say garbage in garbage out.
     
  6. Cees Alons

    Cees Alons Moderator
    Moderator

    Joined:
    Jul 31, 1997
    Messages:
    19,315
    Likes Received:
    289
    Real Name:
    Cees Alons
    You don't need a real converter. A 'speaker-out' signal can be used as a line-in, because the input stage of the final amplifier isn't a serious load to the receivers amps.
    But you need to know if the receiver amps can have it that you don't have speakers connected.

    Make sure you don't set those receiver amps too loud (that will also help diminishing the distortion!), and in case of doubt, buy some 20W (or more) 20Ohms (not lower, but not higher than 50 Ohms) resistors and put them across the speaker-outs of the receiver-amps (parallel to the connection to the line-in of the end-amps). If the resistors get too hot, set the receiver output lower and the end-amps higher. If that isn't possible anymore, you need bigger resistors (more wattage).

    Cees
     
  7. Danny Tse

    Danny Tse Producer

    Joined:
    Nov 1, 2000
    Messages:
    3,185
    Likes Received:
    0
    [​IMG]

    This is what you need. Carver used to make one called, if memories serve me right, the Z-Coupler, and it came in 2 channel or 5 channel versions. As for the performance of such converter, I have no first hand experience. However, I have read that it's OK. Of course, your mileage may vary.
     
  8. EdNichols

    EdNichols Second Unit

    Joined:
    Feb 15, 2003
    Messages:
    372
    Likes Received:
    0
    Thanks for the pic. and info. Based on it's looks and since it has spring connectors I would have to say it probably would not come close to matching the sound of a true pre/pro. But it could be better than nuttin.
     
  9. Tekara

    Tekara Supporting Actor

    Joined:
    Jan 8, 2003
    Messages:
    783
    Likes Received:
    0
    if your aiming to build the item in the picture previously posted, I wouldn't think one to be difficult to make, since both signals are analog a straight connection with no conversion circuitry is possible. wire the black to the outside ring (ground) and the red to the inside (+). this should do it.

    I've used the oposite conversion a few times myself (yes it worked, no it's not that greatby any stretch) by taking off the RCA ends and using the two wires to connect to a speaker.

    radio shack sells all the parts you would need, then just pick up a soldering iron and some solder and away you go.
     
  10. Steve Berger

    Steve Berger Supporting Actor

    Joined:
    Sep 8, 2001
    Messages:
    971
    Likes Received:
    2
    Speaker to line level converters for car stereos are fairly cheap. I got mine from MCM electronics for about $4. I use them to feed my surround speaker outputs to a second Dolby surround amp for a poor man's 6.1 system. It seems to work fairly well. They also have some nice isolation transformers to help remove ground loop hum.
     
  11. Craig_Kg

    Craig_Kg Supporting Actor

    Joined:
    Feb 25, 2002
    Messages:
    768
    Likes Received:
    0
    It worked a treat (I've now upgraded my receiver). I used a 10k Ohm resistor in series with a 470 Ohm resistor for a 20:1 attenuation. The speaker out is bridged by the series resistance (10k Ohm to +ve) and the RCA out is taken across the 470 Ohm resistor (ground to -ve).

    The 'point' is to allow a high quality 2ch system to coexist with a cheap HT receiver.
     

Share This Page