Tubes Asylum: REVIEW: Velleman K8020 Preamplifier (Tube) by ironradio

Model:	K8020
Category:	Preamplifier (Tube)
Suggested Retail Price:	$550
Description:	VALVE CONTROL AMPLIFIER (Tube Preamplifier)
Manufacturer URL:	Velleman
Model Picture:	View

Review by ironradio on September 25, 2001 at 15:40:33
IP Address: 207.225.65.66

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for the K8020

The K8020 uses two 12AU7 tubes and is a nice looking and compact unit. Here is the description from the Velleman site:
o no compromise high-end design
o 4 inputs
o exclusive, high finish, solid aluminium enclosure
o high quality ALPS volume potentiometer
o full valve design
o auto muting (warm up) at power on
o highly reliable reed relay input selection
o separate left and right input section
o programmable level adjustment +6dB for each input
o regulated DC filament supply
o output mute function
o switchable monitor output (for tape, CDR, MD,...)
I found the assembly reasonably straight forward. The quality of the parts were good. The audio quality of the K8020 was very good. However there were some downsides.
I thought the method used to mount the tube sockets above the PCB was a bit poorly designed. The sockets are mounted on pins which mount into the PCB. The two ECC82s (12AU7s) supplied with the kit are best served by their disposal. Their 'brand X' very poor looking tubes and are quite noisy. Instead use Sylvania black-plate JAN 6189W's. The upper PCB which serves as the left channel input module is connected to the lower module with simple tinned, not gold plated, pins and sockets. I can just imagine what's going to happen when a little corrosion sets in. Probably should solder the pins to the main board. The closing of the muting relay does cause a bit of a 'pop' in the output.

Product Weakness: The supplied ECC82s must be replaced, issues with tube socket mounting, poor connection between left channel input module and main module, muting relay noise.
Product Strengths: Simple clean rugged design. Mostly high quality parts. Gold plated input and output connectors. Sonically excellent. Good assembly istructions.

Associated Equipment for this Review:
Amplifier:	Velleman K4040
Preamplifier (or None if Integrated):	Velleman K8020
Sources (CDP/Turntable):	Njoe Tjoeb 4000 CD
Speakers:	Bohlender-Graebener RD50 Ribbons
Cables/Interconnects:	Cableplex Nirvana
Music Used (Genre/Selections):	New Age, Classical
Room Size (LxWxH):	25 x 14 x 8
Time Period/Length of Audition:	6 Months
Type of Audition/Review:	Product Owner

Product Weakness:	The supplied ECC82s must be replaced, issues with tube socket mounting, poor connection between left channel input module and main module, muting relay noise.
Product Strengths:	Simple clean rugged design. Mostly high quality parts. Gold plated input and output connectors. Sonically excellent. Good assembly istructions.