Tube questions...

Early B.
Early B. Posts: 7,900
edited January 2005 in 2 Channel Audio
Which set of tubes contribute the most to the SQ of an integrated amp -- power, driver, or pre-amp tubes?

What is the function of driver tubes?

How many Polkies does it take to screw in a tube?
HT/2-channel Rig: Sony 50” LCD TV; Toshiba HD-A2 DVD player; Emotiva LMC-1 pre/pro; Rogue Audio M-120 monoblocks (modded); Placette RVC; Emotiva LPA-1 amp; Bada HD-22 tube CDP (modded); VMPS Tower II SE (fronts); DIY Clearwave Dynamic 4CC (center); Wharfedale Opus Tri-Surrounds (rear); and VMPS 215 sub

"God grooves with tubes."
Post edited by Early B. on
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Comments

  • organ
    organ Posts: 4,969
    edited January 2005
    IME, they all can make a big difference. Even the rectifier tube made a difference in my amp. Sometimes finding the right combination of driver/power tubes can be fun. ex. using a bright sounding driver tube with very warm, rolled off at the top power tubs.

    Depending on the design, the role of the signal tubs can be a little different. In single ended designs, it's usually to amplify the signal from the pre (or source for int amps) and then is fed to the power tube. I believe your Jolida is a push/pull design, so the signal is first amplified and then the +ve and -ve portions of the sine waves are split up and sent to the designaed power tubes.

    Let us know if it was a bad tube in your amp when it comes in. Let's all hope it was the tube.

    Maurice
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  • Early B.
    Early B. Posts: 7,900
    edited January 2005
    Let us know if it was a bad tube in your amp when it comes in. Let's all hope it was the tube.
    Yeah, just a bad tube. I'm up and running now.

    Organ -- you threw in two more terms -- rectifier tube and signal tube. What do these refer to?
    HT/2-channel Rig: Sony 50” LCD TV; Toshiba HD-A2 DVD player; Emotiva LMC-1 pre/pro; Rogue Audio M-120 monoblocks (modded); Placette RVC; Emotiva LPA-1 amp; Bada HD-22 tube CDP (modded); VMPS Tower II SE (fronts); DIY Clearwave Dynamic 4CC (center); Wharfedale Opus Tri-Surrounds (rear); and VMPS 215 sub

    "God grooves with tubes."
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  • madmax
    madmax Posts: 12,434
    edited January 2005
    On the 502 the two small center tubes are the preamp tubes and the far left and right tubes are for directing the + half and - half of the signal to the appropriate power tube. This is the fun part. They all change the sound in their own ways. The way one sounds depends on all the others. You can spend your life swapping tubes and never come across all the possibilities. :)

    The 502 contains diodes which rectifies the supply voltage. (turns AC into DC). In the old days before semi-conductors they used a rectifier tube instead of diodes. The diodes are very quick. You can ask for a lot of current (because of a music peak) and they deliver. A rectifier tube takes more time to deliver the power and therefore adds a characteristic sound to the music. They also take a little while to come up when the power switch is turned on which makes the tubes last much longer. Both are good depending on what you are looking for.

    Glad to hear it was just a bad tube. Whew...

    madmax


    PS: Never turn on the amp if speakers are disconnected. Also check every now and then that the connections are tight.
    Vinyl, the final frontier...

    Avantgarde horns, 300b tubes, thats the kinda crap I want... :D
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  • organ
    organ Posts: 4,969
    edited January 2005
    Thanks for clearing that up, Madmax. Do you know if the Jolida have a 'soft start' built in? If it doesn't, a techie should be able to install one for you. It should make the tubes last a lot longer.

    Maurice
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