Moniblock Amplifier Series 7R
Croft Acoustics Ltd.; Birmingham
- Country
- Great Britain (UK)
- Manufacturer / Brand
- Croft Acoustics Ltd.; Birmingham
- Year
- 2016 ?
- Category
- Audio Amplifier or -mixer
- Radiomuseum.org ID
- 362009
- Number of Tubes
- 3
- Number of Transistors
- 2
- Main principle
- Audio-Amplification; Hi-Fi-High End products
- Wave bands
- - without
- Power type and voltage
- Alternating Current supply (AC) / 115 / 230 Volt
- Loudspeaker
- - This model requires external speaker(s).
- Power out
- 100 W (undistorted)
- Material
- Metal case
- from Radiomuseum.org
- Model: Moniblock Amplifier Series 7R - Croft Acoustics Ltd.;
- Shape
- Tablemodel, low profile (big size).
- Notes
-
Croft Acoustics Series 7R (Monoblock/Regulated Version)
- Type: Monoblock (single-channel) hybrid power amplifier, regulated version.
- Input Stage:
- Typically uses ECC83 (12AX7) tube, sometimes with additional tubes for regulation (e.g., Tesla 0G3, ECC99).
- Output Stage:
- High-quality MOSFETs, as in the Series.
- Topology:
- Hybrid: tube input, MOSFET output.
- Monoblock configuration: each unit drives one channel, with an independent power supply.
- Power Output:
- 50–55 watts RMS into 8 ohms per monoblock; higher output into lower impedances.
- Power Supply:
- Features a regulated high-tension (HT) supply for the tube stage.
- Larger 300VA toroidal transformer for increased current capability and stability.
- Additional regulation tubes (e.g., 0G3) may be present for voltage regulation.
- Construction:
- Hand-wired, point-to-point, no PCBs.
- Metal chassis for shielding and durability.
- Sound/Performance:
- Improved channel separation, control, and dynamic headroom due to monoblock design and regulated supply.
- Greater refinement, grip, and stability across the frequency range relative to the standard Series.
- Physical Characteristics:
- Each amplifier is dedicated to a single channel, requiring a pair for stereo use.
Technical Comparison Table
Feature Series 7 (Stereo) Series 7R (Monoblock/Regulated) Channels 2 (stereo) 1 per unit (monoblock) Input Stage ECC83 (12AX7) ECC83 (12AX7) (+ regulation) Output Stage MOSFET MOSFET Power Output 45–50W per channel (8Ω) 50–55W per unit (8Ω) Power Supply Standard Regulated HT, larger transformer Construction Hand-wired, no PCBs Hand-wired, no PCBs Chassis Shared with other Croft models Metal, monoblock configuration Sound/Performance Musical, detailed, best with 90dB+ speakers Improved control, separation, and refinement Summary:
The Series 7 is a minimalist stereo hybrid amplifier with a tube input and MOSFET output, designed for high musicality and value. The Series 7R is a monoblock, regulated version with a larger power supply and additional voltage regulation, offering enhanced channel separation, control, and sonic refinement.
- Mentioned in
- -- Original prospect or advert
- Author
- Model page created by Gary Cowans. See "Data change" for further contributors.
- Other Models
-
Here you find 6 models, 6 with images and 0 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
All listed radios etc. from Croft Acoustics Ltd.; Birmingham