Newcomb TR-25 1950s - Burgundy

Big Tube Energy – 4× RCA 6V6

New Mallory Caps!

Oversized vintage transformers. Three versatile channels. Pure American tube tone.

This fully converted and handwired Newcomb TR-25-AM started life as a 1950s PA/Phono amp and has been professionally rebuilt into a powerful, touch-sensitive guitar amplifier.

The heavy-duty original output and power transformers easily handle the parallel push-pull 4×6V6 output stage without compression or sag, delivering deep bass, tight speaker control, and dynamic, responsive feel.

A modern 3-prong grounded power cord has been installed for safe operation.

Features:

• 3 Distinct Channels:

• Channel 1: High-gain channel, converted from the phono input, using both triodes of a 6SC7 for extra gain. Features a bass boost and treble cut for thick, saturated tones.

• Channel 2: Normal channel using ½ 6SC7, great for warm cleans and rich breakup.

• Channel 3: Bright channel using ½ 6SC7 with a bass cut for articulate, cutting highs.

• Switchable Negative Feedback (NFB):

• Toggle between tighter, punchy clean tones or raw vintage response.

• Massive Output Section:

• 4× RCA 6V6GT power tubes in parallel push-pull.

• 6SN7 Long-Tailed Pair Phase Inverter for balanced, dynamic drive.

• Dual 5Y3 rectifiers for classic tube sag and touch sensitivity.

• Oversized Transformers:

• Original heavy-duty Newcomb 32810 TR 146 output transformer and matching power transformer — real vintage iron delivering full-range tone with authority.

• Speaker Outputs:

• Switchable 4Ω / 8Ω output tap.

• Dual speaker jacks for running one or two cabinets.

• Safety Updates:

• New grounded 3-prong AC power cord installed for safe, modern operation.

• Cabinet:

• Heavy turntable mechanism removed to lighten weight while maintaining rugged construction.

• Tubes:

• All tubes are original premium vintage RCA — tested strong.

Condition:

• Fully functional and serviced.

• Vintage chassis shows natural cosmetic wear consistent with age.

• Internal wiring is clean, handwired point-to-point.

• Vintage components preserved where appropriate.

• All original RCA tubes included.

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Specifications:

• Power Tubes: 4× RCA 6V6GT

• Preamp Tubes: 2× RCA 6SC7, 1× RCA 6SN7

• Rectifier Tubes: 2× RCA 5Y3GT

• Channels: 3 (High-Gain, Normal, Bright)

• Reverb: No (ready for external reverb if desired)

• Speaker Outputs: 4Ω / 8Ω switchable, dual jacks