New pre-amp?

Discussion in 'AV Receivers' started by missionm35, Jan 18, 2011.

  1. missionm35

    missionm35 Auditioning

    Joined:
    Jan 18, 2011
    Messages:
    6
    Likes Received:
    0
    Hey guys, first post, thought I'd ask what pre-amp I should get. My current set up is an ADCOM GTP-500 preamp, ADCOM GFA-555 amp, and a pair of Mission m35i speakers.One channel on the 500 went bad, so I'm thinking I want a new one. The set up sounds great on the one channel right now, just need both and it'll be great. So I need a pre-amp with rca and the ability to add in a sub, because I don't think thats possible with the 500.

    Thanks
     
  2. John Brill

    John Brill Supporting Actor

    Joined:
    Nov 3, 2003
    Messages:
    519
    Likes Received:
    0
    If you are looking into getting a new 2channel pre-amp with sub-out, I'd recommend the Emotiva USP-1 (http://emotiva.com/usp1.shtm) at $449. If you want to move into multi-channel, the Emotiva UMC-1 at $699 would be worth the look.
     
  3. JohnRice

    JohnRice Lead Actor

    Joined:
    Jun 20, 2000
    Messages:
    8,813
    Likes Received:
    207
    Real Name:
    John
    I've had the USP-1 for about a month now, and I can say it is a very impressive pre-amp. Excellent sounding, lets you set up either a 2 channel or 2.1 channel music system, and will integrate into a full surround system if you eventually want that as well. If you go 2.1 channel, the sub crossover adjustments are rather imprecise and will take some fine tuning, but once you get it set how you want, it is a real steal. Also, with a sub, it does not have a distance setting, so you will ideally want a sub with some kind of phase adjustment.


    I'm planning to write up an extensive review. We'll see if I actually get around to it.
     
  4. missionm35

    missionm35 Auditioning

    Joined:
    Jan 18, 2011
    Messages:
    6
    Likes Received:
    0
    Is the USP-1 a good match for my amp and speakers, quality wise? Just trying to get a feel for how my stuff stacks up to newer things.
     
  5. JohnRice

    JohnRice Lead Actor

    Joined:
    Jun 20, 2000
    Messages:
    8,813
    Likes Received:
    207
    Real Name:
    John
    My speakers are Thiel CS 3.6 and my amp is an Aragon 4004II. I have owned the same amp you have and I also still own a pair of Mission bookshelf speakers. Both excellent companies who make good equipment, but I can absolutely tell you, both the Thiels and Aragon are distinctly above them in quality. The USP-1 is probably the best 2 channel sound I have heard from them. Not to say there is no equipment available which would be even better, but not anywhere near the price.


    Remember, the USP-1 does not have a tuner. It is strictly a pre-amp.
     
  6. missionm35

    missionm35 Auditioning

    Joined:
    Jan 18, 2011
    Messages:
    6
    Likes Received:
    0
    Apparently the Adcom pre-amp wasn't the problem, I guess one of the the speaker connections was messed up, I'm listening to it all now and it's perfect. Now onto the sub. Is there any way I can tie in a sub into the GTP-500?

    Thanks for all the help so far, sounds like you have some great gear too.
     
  7. John Brill

    John Brill Supporting Actor

    Joined:
    Nov 3, 2003
    Messages:
    519
    Likes Received:
    0

    Yes, get a sub with Speaker Level Inputs and then connect preamp to amp, amp to sub, and then from sub to speakers. In this method, the sub will separate the highs and lows (and good quality subs will allow you to set the cross-over) and send the highs to the speakers.

    As an example take a look at the back panel image for this subwoofer:


    http://www.hsuresearch.com/products/vtf-2-mk3.html You will see the high level input from amplifier terminals and the output to speaker terminals. (Page 4 of the manual explains the connection).


    The only disadvantage to this method is you might get "amp hum" sent to the sub as opposed to clean signals should your preamp had a line level out (i.e. a LFE out, which the Adcom does not). However, I would think that the Adcom amps are high quality that this wouldn't be an issue.


    JB
     
  8. JohnRice

    JohnRice Lead Actor

    Joined:
    Jun 20, 2000
    Messages:
    8,813
    Likes Received:
    207
    Real Name:
    John
    Just an FYI John. High level inputs and outputs pass a full range signal on to the speakers, not a high filtered one. Only the signal split off to the sub is filtered for low pass. The speaker still receives a full range signal. There used to be line level crossover filters for subs, but I don't know if anyone makes them anymore.
     
  9. John Brill

    John Brill Supporting Actor

    Joined:
    Nov 3, 2003
    Messages:
    519
    Likes Received:
    0


    Thanks for clarifying John, you are correct that the full range is still sent to the speakers and that the crossover on the sub is meant more as a signal to the sub which up-to frequencies to play. Normally, you would set the crossover on the sub to the lowest frequency your left and right speakers will output when using the speaker level connection method.
     
  10. JohnRice

    JohnRice Lead Actor

    Joined:
    Jun 20, 2000
    Messages:
    8,813
    Likes Received:
    207
    Real Name:
    John
    I just wanted to clarify that John, because in my opinion, half the benefit of a sub is having the speakers and amp relieved of being fed the lowest frequencies.
     
  11. missionm35

    missionm35 Auditioning

    Joined:
    Jan 18, 2011
    Messages:
    6
    Likes Received:
    0
    The sub has it's own amp inside, its an M&K V-100, will that make the connections any different? So sounds like it would work ok?
     
  12. John Brill

    John Brill Supporting Actor

    Joined:
    Nov 3, 2003
    Messages:
    519
    Likes Received:
    0

    Yes, I believe the M&K V-100 sub has spring loaded speaker level inputs and would work as described above.


    The HSU link I gave you also has a link to the user manual (http://www.hsuresearch.com/products/VTF.pdf) look at step 3 and step 5 for set-up. Should be similar/identical for the M&K.


    As John Rice mentioned above, because your preamd does not have a dedicated LFE output, having a sub in your system will not lighten the load on your amps but will simply play the lower frequencies your speakers may not be able to reproduce. Enjoy and let us know how it works out!


    JB
     
  13. missionm35

    missionm35 Auditioning

    Joined:
    Jan 18, 2011
    Messages:
    6
    Likes Received:
    0
    Sounds good, so will this negatively affect the sound from the speakers at all? I just want tight punchy bass.
     
  14. John Brill

    John Brill Supporting Actor

    Joined:
    Nov 3, 2003
    Messages:
    519
    Likes Received:
    0


    Not at all as the sub will simply act as a passthrough for the signal but will be able to produce the low bass frequencies your speakers can not through the cross-over setting. In fact, with the sub turned off, you shouldn't be able to tell the difference between your old set-up and the new set-up. Once you turn on the sub, that's when you should hear/feel the new bass sound kicking in. Play around with volume and crossover as detailed in step 5 until you are happy with the result.
     
  15. missionm35

    missionm35 Auditioning

    Joined:
    Jan 18, 2011
    Messages:
    6
    Likes Received:
    0
    Perfect, I just have to get the sub fixed and we should be good to go. I have a set of m34s, should I add those, or is that too much for the amp, I know my amp is two channel, but isn't it possible to put both speaker wires into the one amp input?
     
  16. JohnRice

    JohnRice Lead Actor

    Joined:
    Jun 20, 2000
    Messages:
    8,813
    Likes Received:
    207
    Real Name:
    John
    Don't do that. Just use the M35s.
     
  17. John Brill

    John Brill Supporting Actor

    Joined:
    Nov 3, 2003
    Messages:
    519
    Likes Received:
    0

    As John Rice has stated, don't do that. From a purely listening enjoyment perspective, 2 channels and a sub will sound better than 4 channels in stereo.


    If you wanted to use the m34s in another room, you could get a speaker switch box (with a circuit breaker) but do not put 2 sets of speaker wires into an amp output, you are just asking for trouble.
     

Share This Page