1 14

RCA

45 ST RCA Cunningham Matched Pair Black Plates Foil Dimpled Getter Radiotron Tubes Made in USA 1930's

45 ST RCA Cunningham Matched Pair Black Plates Foil Dimpled Getter Radiotron Tubes Made in USA 1930's

€249,90 EUR
€249,90 EUR
Sale Sold out
Taxes included. Shipping calculated at checkout.

 45 ST RCA Cunningham Matched Pair – Black Plates – Foil Dimpled Getter – Radiotron Tubes – Made in USA – 1930s

Description:
This matched pair of RCA Cunningham 45 ST tubes from the 1930s represents one of the most iconic and refined voices in early-era American tube production. Featuring black plates, foil dimpled getter, and a more modern ST-style glass envelope (as opposed to globe types), these tubes retain the full musicality that made the 45 a benchmark in low-power single-ended amplifiers.

Thanks to the precise matching, these two tubes offer symmetrical electrical behavior, ideal for dual mono or stereo single-ended applications with high-efficiency speakers.

Tonality and Sound Signature

Bass:
Light but articulate. The low-end is precise, dry, and natural, with excellent timing and rhythmic articulation. Perfect for those who prefer an agile response that does not mask the details in the lower midrange.

Midrange:
Exceptionally transparent. This region is the real strength of this pair: lifelike vocals, three-dimensional acoustic instruments, and a fluidity that makes every listening session natural and engaging. The sound is present but never intrusive, with an extremely fine tonal texture.

Highs:
Sweet and airy. The treble is extended yet smooth, with a fine grain and no trace of harshness. Excellent rendition of ambient "air" and microdynamic detail.

Dynamics:
Natural and progressive. The response to transients is fast and coherent, never compressed or artificial. These 45s reproduce every change in intensity with musicality and clarity, even at low volume.

Soundstage:
Intimate but precise. The stereo image is centered, well-organized, and realistically layered, with excellent depth and source localization. The stage isn’t as wide as higher-power tubes, but it is cohesive and very believable.

🎧 Use in Single-Ended Hi-Fi Systems
Perfect for SET (Single-Ended Triode) amplifiers offering 1.5 – 2 watts per channel, paired with high-efficiency loudspeakers. This matched pair is ideal for those seeking an organic, fluid, and musical presentation, with special focus on vocal naturalness and overall tonal coherence.

🎯 Note for Collectors and Technicians
These RCA Cunningham Radiotron 45 ST tubes strike a rare balance between historical value, construction quality, and musical finesse. The dual-brand RCA Cunningham label, typical of 1930s production, adds collectible appeal. A matched pair ideal not only for listening, but for experiencing the sound of a bygone era.

Test Results:
Tested with AMPLITREX AT-1000 Tube Tester
Measurements taken after 10 minutes of warm-up.
Test conditions: Vf = 2.5V ; Va = 275V ; Vg = -54.8V
100% Reference: Gm = 2000 ; Ia = 36 mA
Test Result: STRONG

Tube 1: Gm = 1760 ; Ia = 26 mA

Tube 2: Gm = 1570 ; Ia = 25 mA

Additional Tests Performed:

  • Microphonics: Standard – Tested and approved for hi-fi and guitar amp use.
  • Emission Quality: Excellent – Very strong and stable emission, with no fluctuations.
  • Shorts & Gas: None detected.

Condition:

  • Vintage tubes – tested and fully functional.
  • Supplied in our custom protective box.
  • Functional: Fully operational.
  • Cosmetic Condition: Very Good – Print is clearly legible; light signs of age but no major flaws. See photos for details.
  • Manufacturing Code: Not present – manufacturing period based on internal structure. Made in USA, 1930s.

Find out why our valves are different →

Terms of Sale & Safety

Sales Terms & Product Safety

Each vacuum tube is carefully selected, tested, and verified in our laboratory before shipment. Where stated in the listing, test results, matching data, and declared characteristics refer to measurements performed using the specified test equipment and operating conditions.

Sound descriptions are provided for guidance only and reflect the characteristics generally associated with that particular tube type. Personal sound preferences, tube rolling, or perceived differences between audio systems do not constitute a product defect.

Before installation, please verify the tube’s electrical and mechanical compatibility with your equipment and follow the manufacturer’s instructions.

New production and NOS tubes are shipped with a tamper-evident security seal and internal technical documentation to ensure traceability of the product’s condition at the time of shipment.

Product Safety (GPSR)

Vacuum tubes are electronic components intended exclusively for use in compatible equipment and must be installed in accordance with the equipment manufacturer’s instructions.

Due to their historical or vintage nature, certain technical specifications may be based on original datasheets or equivalent technical documentation when documentation from the specific manufacturer is unavailable.

Use only with suitable equipment. Keep out of reach of children.

Shipping & Returns

Shipping & Returns

We ship worldwide using carefully selected express carriers and protective packaging specifically designed for vacuum tubes.

If you change your mind, you may exercise your right of withdrawal within 14 days of delivery, where applicable under the relevant consumer protection laws. The product must be returned complete with its original packaging and accessories, in the same commercial condition in which it was received. Return shipping costs are the responsibility of the customer.

Every returned item undergoes a technical inspection. Installation, use, tube rolling, or any other handling may reduce the product’s commercial value and may affect the refund amount, in accordance with applicable law.

If you believe the product has a lack of conformity, our laboratory will carry out the necessary inspections and apply the remedies provided by the applicable consumer protection legislation.

For further details, Customers are invited to consult the “Terms and Conditions” and “Refund Policy” sections of our website, or to contact us before placing an order.

Vacuum Tubes Treasures
www.vtt.store | www.vacuumtubestreasures.com
📧 info@vacuumtubestreasures.com

View full details

  • ATTENTION PLEASE

    Please understand that the writing on the glass of vintage valves has become very delicate over the years and comes off easily. You must handle them with extreme care to avoid this. Wear and damage to the writing on the valves reduces their market value and causes damage. Please exercise extreme caution.

  • ATTENTION PLEASE

    We wish to inform you that any attempts to manipulate shipping destination information in order to obtain lower shipping rates may be considered fraudulent acts. Please provide accurate information and contact us if you have any concerns. We reserve the right to review and, if necessary, cancel orders that we deem to be in violation of our conditions. Thank you for your understanding and cooperation.