Kenwood ka-7300 amplifier normal/separate switch

Discussion in 'Kenwood-Trio/Kensonic-Accuphase' started by garage inc., Jun 23, 2017.

  1. garage inc.

    garage inc. New Member

    Messages:
    26
    Its good to have the splitters anyway in case the normal/separate switch contacts wear or break, should be interesting I had a Lafayette lr 9090 receiver with two Dayton 250 watt plate subwoofer amps, these amps had high level inputs so it was easy to connect & they levitated the garage, the 1000w should be very therapeutic.
     
  2. roger2

    roger2 . Subscriber

    Messages:
    2,925
    Location:
    indiana
    No need to go to the trouble of buying splitters if they are not needed. That switch likely won't break. Its contacts could be dirty the same as every switch in vintage gear could be. I would try without the splitters first.

    https://www.parts-express.com/rca-y-adapter-2-male-to-1-female--240-125
    https://www.parts-express.com/audte...o-dual-rca-male-y-adapter-cable-1-ft--181-451

    Also found this on ebay. There are probably others there as well, I did not scroll through...
    http://www.ebay.com/itm/Qty-2-7-RCA...908190?hash=item339bf5c85e:g:xe8AAOSwYvFZIdGj
     
    Last edited: Jun 27, 2017
  3. garage inc.

    garage inc. New Member

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    26
    I believe I have monster cable splitters some where from a multiple car amp project I did a long time ago in spaghetti wire cabinet drawers in the garage.
     
  4. Collin1141

    Collin1141 Well-Known Member

    Messages:
    625
    I'm not confused
    I also owned a KA-7300 for roughly 10 years
    If you set the switch to separate, same as pulling U-hooks, then you can only use the power and the pre as separate components
    That switch, same as U-hooks, allows an owner to use his KA-7300 either as a
    1. Integrated amplifier
    2. Pre-amplifier
    or
    3. Power amplifier
    The ONLY way to use #2&3 simultaneously is to either introduce a third amplifier into the equation OR drive the power amp with a high output component like a CD player IF it allows for volume control OR another pre-amplifier
    And that still won't solve what he wants to do
    If he uses splitters as you suggest, he will NOT be able to control the volume of his main speakers, use tone controls, switch components (so you can hear them anyway) with the pre-amp section disconnected from the POWER AMP
    That's IT
    FULL STOP
    JUST RUN THE SUB(S) OFF THE TAPE LOOP
    I don't know why you have a problem with that? You're not going to have a true master volume control with this set up anyway, you're going to have to match the sub with the mains

    You guys take it easy
     
    Last edited: Jun 27, 2017
  5. Collin1141

    Collin1141 Well-Known Member

    Messages:
    625
    No, with the exceptions noted below and elsewhere
    The speaker taps on the power section will only output signal if
    A. the pre is connected via the switch
    or
    B. you are feeding a line level signal of some sort "IN" to the power amp, whether it'a another pre-amp, CD player with volume control etc
     
  6. roger2

    roger2 . Subscriber

    Messages:
    2,925
    Location:
    indiana
    To use your numbering above, #2 can power #3 as though they were not mounted on the same chassis. You have a pre-amp, and you have a main amp connected to speaker outputs. No other components needed. Add in an additional tap from the pre-amp via the Y splitter and you can power a sub. All functions of the pre-amp will apply. And yes, in the connection as described by 3 of the 4 people in this thread, the KA-7300 main volume will serve as a master volume for main amp as well as sub. Using Tape outs is simply a bad idea for reasons already explained.

    Peace out. We can simply agree to disagree for now. No point in getting jacked up over this. Let garage inc. do his hook-up and report his results.
     
    Last edited: Jun 28, 2017
  7. Collin1141

    Collin1141 Well-Known Member

    Messages:
    625
    Not agreeing to anything friend
    He'll know after he wastes more time and money on splitters that his only option with what he has now is to run his subs off his unused TAPE loop
    The KA-7300 makes no provision for bass management and the pre and the power sections are either connected or they aren't
    It's not that complicated
    He wants to run his main speakers AND his subs off the old Kenwood and you CANNOT do that, AT THE SAME TIME with the two sections separated
    The volume control ain't going to do jack for his MAIN speakers with the switch set to separate
    Use the tape loop
     
  8. roger2

    roger2 . Subscriber

    Messages:
    2,925
    Location:
    indiana
    The KA-7300 main volume controls the level of the pre-out signal (all of the tone controls also affect the pre-out signal). With a splitter on the pre-out connecting to both the sub and the KA-7300 main-amp inputs, the KA7300 volume knob would then control both the KA-7300 main amp as well as the sub.

    What is "bass management"? Are you referring to something from the AV world? Bass management in the OP's situation is handled by the controls on the sub's amp: main level (used for matching the sub to the main's then left alone), HF cut-off point, LF boost (optional), and phase (also optional).
     
    Last edited: Jun 27, 2017
  9. hopjohn

    hopjohn Kenwood Krazy Subscriber

    Messages:
    931
    Location:
    Dallas, TX
    I took a look at the schematic to see how the normal/ separate switch behaves. In the normal position the preamp is fed to the internal amp input, and the power in RCA connections are put out of circuit. In the separate position the preamp is disconnected from the internal amp input and the RCA power in connections are put into circuit to feed the internal amp input. The RCA preamp outputs are hard-wired. That is to say that they are connected to the internal preamp output with the switch in either position.

    In this case, the OP can just leave the switch in the normal position, connect his speakers as normal to the KA-7300 speaker outputs and use the RCA preamp outputs to his plate amp. Then he should gain match the subwoofer output, and set the low pass frequency at the plate amp. Master volume will of course controlled by the 7300.
     
  10. garage inc.

    garage inc. New Member

    Messages:
    26
    Thanks hopjohn, clanegg & roger2. I think collin1142 is confused, he keeps referring to the ka-7300 as stand alone, he doesn't realize I am adding an extra amplifier, he states the kenwood ka-7300 can't simultaneously by itself connect the pre amp to its own power amp. What advertising that would be for kenwood back in the 1970's: Here we are selling an amplifier that produces no sound, lol. thanks again
     
  11. Collin1141

    Collin1141 Well-Known Member

    Messages:
    625
    Nope, Collin1141 isn't confused
    This is what I wrote (several times) and in as many ways
    Not good form to flagrantly misquote and mischaracterize people's posts
    Especially when they're trying to help you
     
  12. hopjohn

    hopjohn Kenwood Krazy Subscriber

    Messages:
    931
    Location:
    Dallas, TX
    Colin you are arguing against a position that no one is taking. When using Y-splitters in the way roger2 suggests you are effectively reconnecting the two "sections" and thus you would be "using it as an integrated" even though the switch is in the separated position. One end of the Y-cable is being used as u jumper going from the preouts to power in RCA jacks and the other ( what makes it a Y ) would feed the sub amp. I don't see reason for disagreement, but perhaps this reconnecting of the preamp and main amp with the Y-cable point is lost on you.

    Again, the way that the 7300 is internally wired eliminates the need for the Y-splitters because the signal output of the preamp is split to the RCA preout jacks and the amp input simultaneously when the 7300's switch is in the normal position. So I guess it could be said the Y splitter is built in, thus no need for it.
     
    Last edited: Jun 28, 2017
  13. garage inc.

    garage inc. New Member

    Messages:
    26
    I don't know if your allowed to modify a posting or thread but how could I hook up a vintage graphic equalizer to my scenario having the Dayton plate amp still hooked up to the pre outs, full range sound still coming out of the ka-7300 speaker outputs & still have ka-7300 volume control with the equalizer now shaping my midrange speakers & tweeters.
     
    Last edited: Jun 28, 2017
  14. hopjohn

    hopjohn Kenwood Krazy Subscriber

    Messages:
    931
    Location:
    Dallas, TX
    Alright, alright you're just trying to complicate matters aren't you? ;)

    For this scenario, put the 7300 in separated. Connect your main speakers to the speaker outs of the 7300. Use Y splitters at the preout jacks. Feed one end of the Y cables to the plate amp of the sub line level inputs and feed the other to the EQ inputs. Then feed the EQ outputs to the power in RCA jacks of the 7300. You'll only have EQ control of the main speakers this way, but your sub should have provisions for EQ management if it's the Dayton plate amp I think you are buying.

    Edit: Also if you are using an external EQ I'd suggest leaving the KA-7300 tone controls off. You could potentially damage something trying to make use of both at the same time.
     
    Last edited: Jun 28, 2017
  15. garage inc.

    garage inc. New Member

    Messages:
    26
    Awesome, yes tone controls on kenwood set to flat, the equalizer gives me more things to fiddle with in my garage control center, thanks again to all.
     
    Last edited: Jun 29, 2017
  16. Longhorn262

    Longhorn262 New Member

    Messages:
    41
    Little education on how pre-amp, amplifier inputs and splitters work. I have done what Roger suggested on multiple receivers one of them being a Kenwood 7300.

    Pre-amp takes a low level signal via phono, tape or aux and "boosts" the voltage. It also allows you to attenuate "control how loud it will be" via a volume knob. Depending on pre amp section you will also have bass, treble, balance controls, etc. This leaves the pre-amp jacks in separate mode on the back or it can be tied to the amplifier in normal, same as using u-shaped hooks or a y splitter cable. So in normal the pre-amp sends a modified signal to the amplifier. You can tap into the pre-amp section even in normal mode with out using splitter cables like I do on my Technics great job Kenwood even for late 70s. This means the pre-amp can run the power amp and a remote subwoofer amp or any other amplifer for that matter.

    For example I have my TV audio and turntable run into my 80s Technics receiver this allows me to listen to some small custom bookshelf speakers 60watts and control volume with a remote along with different eq settings. It has preouts and main in on the back so I ran a splitter off the back which feeds a subwoofer plate then splits again to feed my 7300 which powers a set of Klipsch kg4's. So if I want to let the neighborhood know what I'm listening to I flip on the Kenwood and crank the Technics up which in turn cranks up the Kenwood and sub simultaneously.

    Hope you learned something new :)
     

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    Last edited: Sep 6, 2017
  17. garage inc.

    garage inc. New Member

    Messages:
    26
    Thanks on that longhorn, I just bought the Dayton 1000w amp & just finished building crossovers for the tweeters & midrange speakers, high pass & band pass, now I am working on building the speaker cabinets. I had a nice setup up in the garage until my wife pulled in, swiped the passenger side mirror on the garage door metal rail then just hitting my 7 foot tall speaker enclosure tipping it forward taking out three shelves that had my Lafayette lr-9090 receiver, two Dayton 250w amps & a vintage equalizer trashing all three, I salvaged the subwoofers in the towers but the cabinets cracked like accordions being old moisture ridden mdf, pretty comical I think now, lol.
     
  18. Longhorn262

    Longhorn262 New Member

    Messages:
    41
    Sad to hear :(

    I'd like to hear how that Dayton 1000 turns out. I've been wanting to get the monster Dayton 18 and pair it with that amp for a couch shaking theater experience.
     
  19. garage inc.

    garage inc. New Member

    Messages:
    26
    I will post with pics after building the speaker cabinets, they use four 4 ohm car subwoofers, two 6x9's & two phenolic tweeters, very time consuming & heavy, figure another month or two. I like car speakers, they are made heavier than home speakers & perfect for the garage with the spiders & crickets & occasional small lizard we have here in Virginia. I screen the port tubes in the speaker cabinets so nothing climbs inside & I find the screen silences any air huffing port tube noise from the heavy bass & you can still feel the port air hitting you when standing 6 feet away from the tower, lol.
     

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