As the RCA manual states - the characteristics may fall in a range above or below the bogey values when testing tubes. It’s speculated that the way the side getter is mounted to the plates contributes to the low microphonics on these tubes.
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The most distinctive sound feature of the Heerlen ECC83's is the transparent, natural and expansive midrange presentation, with a slight touch of warmth that illuminates your music. Every piece of music you play through these tubes sounds like from a vinyl record, whether your sound source is phono or not.
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Getter: Side "D". Plate(s): Long(17mm) Grey Ladder. But this the way of the world now. We are always looking to buy more tubes. Large collections, small collections, it doesn't matter. Looking forward to hearing from you, Dan.
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This tube tested at 93% "Emission quality" on my basic Sencore tester where 70% and above is considered good emission quality. I'm assuming it is NOS. Last two photos are for my reference.
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TESTED GAIN (89.4, 94.9) RAYTHEON?. FOR BALDWIN 12AX7A / ECC83 TUBE MADE IN JAPAN. While performing an audio tap test on the Maxi Preamp through a guitar amp Triode A tested good when tapped, Triode B tested excellent when tapped.
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The Marconi 5814 vacuum tube is considered a high-end variant of the 12AU7, prized by audiophiles and collectors for its exceptional build quality and performance. Here’s an in-depth breakdown of its features, history, and value.
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Up for sale is a Raytheon 12AX7A ECC83 NOS NIB single tube, tested for quality. This vintage tube is perfect for audio enthusiasts looking to add to their collection. Made in the United States, this tube is a rare find and guaranteed to be of top quality. Don't miss out on the opportunity to own this piece of audio history.
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