The Glastonbury Pre 1 Autotransformer Passive Stereo Preamplifier is a High Fidelity line level control centre that selects 6 inputs, adjusts gain and supplies two outputs. The Glastonbury Pre 2 is a fully balanced version of the Glastonbury Pre 1.
The heart of the machine is the 30 tap Fractal-Wire™ wound autotransformer with 80% Nickel mumetal laminations for ultimate performance.
The 6 position input selection is by manual control by the left hand rotary selector knob.
The gain is adjusted by the right hand control knob, which is primarily remote controlled but may be operated manually.
There are 6 stereo RCA phono inputs, two of which have parallel XLR connectors and two phono stereo outputs with parallel XLRs.
The XLR connectors are unbalanced in the Pre 1 version and fully balanced in the Pre 2 version. This entails the addition of eight 1:1 Fractal™ wire wound transformers to achieve fully balanced operation and galvanic isolation to prevent any possibility of hum due to ground loops.
The gain (or volume) control is by a 24 position rotary switch divided into 2dB increments which provides a gain range from +6dB to -40dB. For low level listening, there is a further remote controlled – 10dB function which reduces the gain overall by further 10dB to -50dB.
For fine gain adjustment, there is a remote controlled +1dB function available at all volume settings which yields a total range of 57dB in 1dB increments from -50dB to +7dB.
There is a remote controlled Mute function and a remote controlled Mono function for optimum mono LP listening that eliminates stereo noise on mono programme.
The Preamp is overall DC coupled. However, if there is one source component with a DC offset in excess of about 5mV, this component should be connected to input 6. Associated with input 6, there is a rear panel mounted switch which allows the connection of ultra-high quality capacitors in series with the input to eliminate saturation induced distortion.
The external power requirement is exclusively for the control circuitry. This is provided by a 15V, 1A DC mains powered universal wall mounted AC to DC converter. There is no connection between the control circuitry and the signal circuitry. The circuit is normally in “sleep mode” and only becomes active when changing volume to eliminate the possibility of switching noise.
The unit will function without power on purely manual control, but there is no +1dB, -10dB, mute or AC possibility.
All internal signal connections are by Fractal™ wire.
The Pre 1, when DC coupled (normal) with the volume control set at 0dB, the signal is connected directly from the input to the output.
As this is a purely passive device, there is no mains-born noise degradation. This, when combined with Fractal™ wire, results in the most accurate, uncoloured and open sounding preamplifier possible. ASTONISHING!
The case comprises a 12mm thick solid front panel with 6mm thick top and sides panels, with the remote control machined out of a solid block, all manufactured from natural-anodized and brightened aluminium for the most luxurious appearance and feel. The case is supported on four vibration isolation feet.
Frequency response
8Hz-100kHz +/1 0.1dB
Maximum signal level
4VRMS 8Hz
10VRMS 20Hz
Maximum DC offset
5mV (for undistorted 8Hz when set to DC)
Distortion
less than 0.01% 400Hz 10V 2nd and 3rd harmonic only
Impedance
The input impedance is dependent upon the load impedance and the gain setting.
So, with a power amplifier having 20k input impedance (typ)
At 0dB, the input impedance is 20k
At -10dB (normal listening) the input impedance is 200k
At + 7dB gain, the input impedance is 2.5k
Inputs
6 Gold plated stereo RCA phono sockets
2 Gold plated XLR sockets unbalanced
Pre 2 balanced
Outputs
2 Gold Plated stereo RCA phono sockets
2 Gold plated XLR sockets unbalanced,
Pre 2 balanced
Power
15VDC 1A (remote control only)
Physical
Width 490mm (19.3”)
Height 120mm (4.7”)
Depth 380mm (15”)
Weight 11kg (24lb)
Glastonbury Pre - HiFi Critic review
Distinguished and most respected reviewer Martin Colloms of Hi Fi Critic magazine awarded the Glastonbury Pre1 preamplifier an unprecedented 195 points. This is the highest mark ever for any product since the introduction of the MC scoring system some 30 years ago. This indicates just how impressed Martin is with the Glastonbury Pre 1.
“It’s fairly easy to make a general purpose active pre-amp, yet surprisingly difficult to make an excellent one”
Sound
“There was no doubt at all about its exceptional musical ability. Ironically, rather than representing a specific ‘improvement’ in sound quality on the part of the Glastonbury Pre 1, this is more of an aspersion on the vast majority of control units, which are nothing like as truthful as this, to put it mildly. On my comprehensive scale, this control unit, as supplied in single-ended form, reached an exemplary 195 points for overall sound quality”…
“To be truthful I found it difficult to lay a finger on its aural performance. Bass lines seemed deeper, more visceral and tactile, more dynamic, and more expressively detailed than usual. The mid was very neutral, highly transparent and well-focused, with very natural high level sounds and most revealing and detailed low level sounds. The high treble was very slightly distant, a really small effect, but remained of excellent quality. Complex material was rendered with impressive differentiation and separation, with very natural and believable instrumental tone colours. It clearly had very good rhythm, and sounded most uncontrived, non-electronic, almost perfectly natural if I can put it that way. Stereo image width, focus and depth were all exemplary.”
Measurements
Most results are so perfect as to not be worth relating…
Conclusion
“Max Townshend has painstakingly exploited auto-transformer technology to deliver a most truthful and non-invasive passive line controller, combining expertise in transformer design, materials technology and advanced conductors. This is one of the most accurate and neutral line controllers made, and at present defines the state of the control art.”
Source: HiFi Critic, July – Sep 2011
Pre-amp review on Hi-Fi+
Glastonbury Pre 1 gets a “flipping glorious” review from J. Kennedy in Hi-Fi+
Jason Kennedy, writing for issue 81 of Hi Fi Plus, August 2011, finds that the Townshend Audio Glastonbury Pre 1 Preamplifier delivers; “power“, “solidity” and “sheer transparency…There are very few preamplifiers around that are as resolute as this passive device“.
When the Glastonbury Pre 1 was heard on the fully integrated Townshend system, comprising the vibration isolated Glastonbury Tor speakers; Rock V turntable with Excalibur 3 arm and TA Cables, Kennedy says of the system “as a whole, is pretty extraordinary in its resolving powers“
Kennedy suspects that the preamp “has as much to do with that as any other part. It’s uncompromisingly revealing in seemingly all respects and is uncannily open whilst avoiding the subtle hallmark that electricity seems to leave on virtually all active preamps” although Kennedy explains that this might be something that some actually enjoy as it tends to imbue the music with a certain: “extra energy that some consider to be lacking in passive devices, however this controller proves that you can have your cake and eat it”.
Kennedy finds “The Glastonbury delivers as much grunt and energy as a powered preamp, dynamics are as wide if not wider than can be achieved with active devices and there is a sense of hearing the pure energy from the recording rather than that energy with the subtle reinforcement that even the highest quality electronics impart“.
Kennedy also observed that; “Bass lines are, to coin a phrase, flippin’ glorious” and, in summary, “…..it is the most revealing preamplifier I’ve used.”
To listen to the Glastonbury Pre 1 in the new complete Townshend Audio Reference system, please contact us for a demonstration at our Hampton Court venue, where you can hear for yourself your favourite recordings in High Fidelity like you’ve never heard them before.
The closest approach to the straight wire with gain.
