Wednesday, June 28, 2006

Trace Elliot V8

Trace Elliot V-Series V8

The legendary Trace V8 was one of the last original Trace Elliot tube amplifiers designed and produced in the UK. While this production happened under the watchful eye of Gibson's Gnashville headquarters, these amplifiers remained true to the original vision. Fewer than 80 of these amplifiers were produced and are considered by many to be "the grail" of all-tube bass amplification and in the same league as the infamous HiWatt DR-405 amps used by John Entwistle.

The two-channel preamp features a 7 tube compliment driving 8 x KT-88 power tubes to produce a massive 400 watts of power. This amplifier also features an EM84 "power indication" valve which displays the output relative to 400 watts RMS. The staggering power output of this all-tube amplifier is truly unbelievable. Thankfully there is a half-power switch.

I had been on the hunt for a HexaValve and ended up spending a great deal of time on the phone with Trace Elliot's UK service manager. After some discussion he advised me to snap up a V8 as soon as they became available, hinting at some trouble brewing between Gibson management and the remaining Trace Elliot employees. My amp was shipped to me direct from the UK instead of through the existing distribution channel, one of the first production units. It wasn't long after that Gibson dismantled the original Trace Elliot UK facility.

According to the V8 manual "The circuit topology of the V8 has been based on traditional valve amplifier designs,with new ideas incorporated where beneficial for either sound quality or production efficiency. The main signal path through the preamp and power stage sections is 100% valve, relays have been used for all the switching functions, and integrated circuits have been used in the DI circuit for quiet operation and impedance matching for 600 ohm mixer inputs. The chassis is made from gloss black, stove-epoxy coated, 16 gauge zintec. Cabinet is made from 3/4” plywood. Highest quality porcelain valve sockets have been used throughout for the KT88’s,ECC83’s and EM84. The power and output transformers have been custom made by Demeter specifically for the V8 for maximum performance using high grade laminations. Windings are resin soaked and manufactured to pass international approvals. A highly regulated DC supply is used for heater filaments in all preamp valves for minimal hum levels. An external biasing facility is featured - this enables techs to check/reset output bias at any time without removing the chassis. Internal wiring and glass epoxy circuit board layouts use multiple return star earthing for low noise and hum. All audio sections have been laid out for sonic performance using ‘point to point’ wiring principles. Gold plated jack sockets are used exclusively throughout. Two quiet chassis mounted fans keep the power output valves at safe operating temperatures even when playing at high volumes."
The selectable compressor circuit within the V8 is based on simple vintage studio valve compressors. It’s valve gain stage is controlled by a silicon diode side chain that has been designed to respond like a vacuum double-diode. It has pre-set slow attack and release times (best for bass frequencies) and is intended to be used to smooth out and fatten up the sound of a bass guitar (rather than as an extreme limiter effect). Other features include a serial effects loop, transformer-coupled DI switchable to pre or post modes with a ground lift switch. There's also a full/half power switch.

The V-Type V8 is powered by eight KT88’s. These are configured for grid biased class A/B operation. This is the traditional arrangement for a high powered amplifier of this type, to efficiently produce at least 400 watts with the valves supplied (at the rated nominal mains input voltage).

Four panel mounted fuses protect each pair of output valves. There is also a rear panel bias adjustment for each pair of tubes. If an output valve starts to draw too much current, the corresponding fuse will blow, turning off both valves in the pair and lighting the LED underneath. This will result in a reduction of output power but the amplifier continues to function.
Pictures of "the innards" by Rich Heslip.

My thought when buying the V8 was that it would serve as a "poor man's DB680+DB728", but it turned out to be nothing of the sort. This amplifier is a totally different beast. What it does share in common with the aforementioned Aguilar DB setup, the HiWatt DR-405 and the original vintage Ampeg SVT is that it is also one of the finest all-tube bass amplifiers ever built.