Audio Research VT50 Review

by James Leahy

 

                                                                                 Introduction

The Audio Research VT50 is the baby of the VT series and is rated at 45 watts per channel. It uses four Svetlana 6550C output tubes in an ultra-linear circuit design and four Electro-Harmonix 6922 tubes for the input/driver circuit.

There are eight Nichicon capacitors that contribute to this units lightning fast frequency response and dynamic impact. With a total of 354 Joules of energy storage which is a lot for an amplifier this size which is reflected in the bass extension. The VT50 series was first introduced in 1998 and is just like a miniature VT100 Mk.II. It has the same powerful and gutsy drive that can be felt as well as heard.

 

 

The front panel has Audio Research's simple toggle power switch for operation. Around the back, it is again rather simpler with 4, 8 and 16 ohm loudspeaker binding posts.

There is a choice of either 'Single Ended' or 'Balanced' inputs to select from. This is a very nice feature on an amplifier of this size and price. More on this later. If Single Ended inputs are used the need for shorting pins in the Balanced input is necessary.

The circuit is of a fully Balanced design and is dual mono in construction. The main internal circuit boards for the left and right channel are mounted vertically and are well laid out with plenty of space for maintenance and cooling. The factory Svetlana 6550C tubes are the best I have used and I would not advise changing to any different brand or spec units.

The bias adjustment is ultra easy with the top cover being removed there is a trip pot provided on each circuit board and a conveniently located bias resistor along the top most edge.

 

 

The quality of construction is no different to it's bigger brother the VT100 series and if you are in a small listening room of around 4m x 6m then you may wish to consider this amplifier as a cheaper alternative if power requirements are not of the primary importance. I have found it to be more than capable to drive my 89bD efficient floor standing loudspeakers to high levels without distortion or disturbing lack of bottom end bass. The VT50 is one of the best value for money 50 watt or less valve amplifiers on the market and can be picked up used for a bargain price if in good condition. It is of a timeless design that will suit many tastes with it's fully enclosed chassis providing all-round protection for the tubes inside. Handy if you have small children.

 

 

                                 Sonic Evaluations

The VT50 is a great performer when it comes to bass impact from a 45 watt amplifier. It certainly has the legs over and above the newer VS55 in this area and provides the listener with more snap in it's transient response. The performance was an amazing 50% better using the balanced inputs from my ARC LS26 pre-amplifier with the VT50 than single ended inputs from the same unit. Maybe this was more the LS26 but anyhow it was substantially better whatever the reason. The bass response tightened up even more and the dynamics increased to higher levels. I would strongly advise if your system has the capacity to do so you make the effort to use the balanced inputs. A good pre-amplifier is not wasted on this amplifier, that's for sure.

 

The soundstage is very dynamic for an amplifier of this size and it will not produce any unflattering midrange dryness like some. I enjoyed this amplifier more than the V70/Classic 60 line as I find the VT series easier to live with especially the versions using the 6922 input/driver combination. The timbre and midrange tone is very neutral and virtually identical and in the same vane as the VT100 Mk.II and VT200 Mk.I in nature, only smaller. Listening to my system with the VT50 I was not left wanting more impact at moderate listening levels and I found this amplifier very enjoyable to listen to for extended periods. There is not any shrill treble to complain about, but smooth extended top-end with a very solid image. The shape of the sound is inoffensive and easy to match with a host of different front-end components.

JJ Cale's - 'Troubadour' album (Shelter Recording Co, 1976) showed up all the attributes that I love in my big VT200 Mk.I. The sound is not only full but the soundstage is wide and deep without any hint of thinness. It just asks to be played and played, so enjoyable is the presentation of dynamics and rhythm from this little powerhouse. The top end is not harsh or fatiguing to listen to for long periods which is the classic house sound of Audio Research and the midrange is full of body that grabs you and makes you give your full attention over. All in all a very complete little package that would complement any small sized system. 

 

 

Associated review Equipment

  • Line Stage:         Audio Research LS26

  • Phono Stage:      Audio Research PH5

  • Speakers:           ScanSpeak & Vifa Custom

  • Cables:              Neotech

  • Cartridge:           Ortofon MC Jubilee

  • Turntable:          Rega P7

  • Subwoofer:         Velodyne HGS-15

  • CP Player:          Sony SCD-XA777ES