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HG Transistor input power question.

Discussion in 'Amplifiers' started by Capt Crunch, Mar 19, 2020.

  1. dave457

    dave457 Sr. Member

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    1200 watts pep from four 2879's..... I'm sure that looks great on a scope


     
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  2. Capt Crunch

    Capt Crunch Captain Crunch NJ Mobile

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    I agree! I have read his builds are really good and saw from a video review of one of his amps on a scope was reviewed as very good. That being said, he didn't rtest it like Carl did. LOL
     
    530 likes this.
  3. Shockwave

    Shockwave Sr. Member

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    Differences in amplifier design have as much to do with drive requirements as the specific transistor being used. Variables like bias, impedance matching, turns ratio, negative feedback and resistive or capacitive padding can have a large impact on drive requirements using the same transistors.
     
  4. Capt Crunch

    Capt Crunch Captain Crunch NJ Mobile

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    All good, don't understand this side of it. I do know the guy said 5 watts minimum when I messaged him, and his videos for these he drove it with 40 watts and with 200 watts pep. Again I understand these transistors can take more than typical datasheet specs but I also see them blown run at those higher than the rated specs. Plus I read several of what happens running them at the high a drive like HMD and splatter. Not much of a technical guy but I do read and try and gather what's correct and what's not. I am just not seeing where tis really ok to drive these so high. Every video I see drive testing all the 2879s they all eventually blew out. He said minimum is about 5 watts is all you need to key the relay, so I think until I understand fully about HD amps I will be going by the 2879 specs sheet. I was going to run my 6666 with it but I think I will play it safe for now and run it with my DX979. Reports are excellent for both but some are saying with the 6666 running like Carl did on these amps in videos with 40 watts pep, I sound louder, carrier went up a little, not as clear but still sound good. Obviously not a technical way to test but it was noticed by 4 people in different places.
     
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  5. 2NC995

    2NC995 DAN

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    Have you tried it with the 979 yet?

    The numbers on his website are interesting...200W carrier from amp. Back in the Toshiba days you could run double that from a straight 4 class C amp as a "daily driver".

    At the same time, 200W peak input is recommended max. Hard to wrap one's head around.



    Also interesting:

     
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  6. Capt Crunch

    Capt Crunch Captain Crunch NJ Mobile

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    Using the 979 now. I know, right. Again I understand people have overdriven these as per the 2879 specs claiming over 200 watts pep each, but then again I have seen videos of people running that high in tests and they all eventually blow out. Granted again not sure how long that would take in real world usage and maybe they would last a long time but I have seen repairs to all the big name amps with blown transistors. Not to forget to mention HMD and splatter and all that other technical stuff, and then I see some saying its not really that bad to do. LOL. That's why I think until I really know what the deal is with HDs and if they really have something in them that makes it "ok" to overdrive these transistors I'm running it at 5 watts DK around 25 PEP. People say I sound crystal clear and I'm happy with it the way it is, at least until I really know what's going on with HDs. Years ago I read some just buffer down the extra driver wattage but not sure. I mean look at the old 667Vs, I had one, definitely specsheet overdriven with a Sommerkamp 2000DX(2950) into the 2290 into the overdriven 2879s and mine lasted at least 6 years before I sold it, working. LOL
     
    #21 Capt Crunch, Mar 27, 2020
    Last edited: Mar 27, 2020
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  7. 2NC995

    2NC995 DAN

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    Life is much simpler just babying things and letting them idle along...so much less to worry about.

    With truck the truck running at high idle I see 400 or so watts from my DX500. But, I most often run the amp off just my truck's battery voltage, and typically for hours on end. Can't imagine it's making but 300 watts or so, but I don't really care. In the alternative, if I fired up the truck and maxed out the input - running everything full tilt - it might just barely make a perceptible difference on the other end.
     
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  8. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    One of our locals has a 1 driving 2 in his truck. He has a Stryker 447 running into it. You can imagine what it sounds like. Just because you can doesn't mean you should.
     
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  9. 2NC995

    2NC995 DAN

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    He just needs a bigger amp...but then he’d run it the same way. Lol.

    I often think about buying a DX1600 for the pickup, and moving the DX500 indoors...but my senses remind me I wouldn’t accomplish anything beyond killing my batteries faster.
     
  10. Handy Andy

    Handy Andy Do Your Research First, Then Decide...

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    Hmmm...

    Not sure if I should ask, but I'm going to here because it seems to make more logical sense - just remember I'm not here for arguments - just some clarity...

    Just wondering if HG or anyone else these days, are still doing up test Jigs so the rest of us can see what they idealized to - or do we need to start looking into redesign and a whole new set of values, blocks, dimensions and other toys to play in the sandbox...?

    Because whomever can idealize the part to fit the need - wins. At least in the Days' of Motorola, and they open sourced it for the reasons of finding more real-world data to add into their datasheets. On top of that, the rest of us never knew and learned by their experiences.

    I have to ask, and not it's not for arguments just observation - so is HG simply a copycatter (best word) or are they breaking new ground on the die designs and letting us kids play in the sandbox with them and they review the data from us -as our gripes and complaints-praises and petunias, and marginalize or improve the design as they go?
     
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  11. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    I think they want to make something that works just enough for people to buy it.
     
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  12. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    The 1600 would be great on my 955. It will use a lot less power if you are running it easy.
     
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  13. 2NC995

    2NC995 DAN

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    Don’t talk me into it, Chris. I don’t need help spending my Coronavirus stimulus check. :ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO:
     
    Capt Crunch likes this.
  14. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    Oh no, you had to go there.... Maybe a pair of 1600s put together with combiners and splitters like the Viking?
     
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  15. 2NC995

    2NC995 DAN

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    I like the way you think, lol!
     

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