Harma Valves / ECC83/5751-HARMA STR HG

ECC83/5751-HARMA STR HG ECC83/5751-HARMA STR HG Click on image(s) above to view larger

All prices contained on this page are exclusive of VAT. This is currently charged at 20% and is payable by the UK only.

A test report is available click here to view

Harma valves consist of a selected range of valves that are chosen after meeting stringent standards for sound quality and reliability. These valves are sourced from current production as well as some of the finest Nos valves available. Unlike our competitors no Harma valves, past or present has been made in China. Harma valves represent the finest available items of their type available.

Harma valves are tested using a range of custom designed and built test rigs which are unique to Watford valves.These unique tests are not offered by any other valve supplier in the world.

All Harma pre amp valves undergo the drive rating system; the valve undergoes a series of through tests under full operational conditions. This involves a controlled burn in process to ensure perfect stability and correct ageing. A shock and vibration test, microphoney, hum, and a balance and symmetry test.

All Harma output valves undergo our own unique real world burst testing. No other supplier tests valves this way. The burst testing process involves a series of varying timed electrical signal bursts. This runs the valves under the same stress conditions that they will meet in your amplifier especially when overdriven. All out put valves are then dual matched by us on anode current and gain. This will ensure that you get the best selected valves available anywhere in the world.
The Harma 5751 STR has been specially selected to offer reduced distortion and gain level. All modern made 5751 do not drop the gain as much as the Original USA made 5751.

All items, Sovtek ,JJ, Electro Harmonix & Tung sol valves have more gain when compared to an original USA made 5751 which drops the gain by 30%.

So the Harma 5751 STR is selected to be as close to the original USA made item gain as possible.

The Harma 5751 STR valve has been specially selected to offer typically around 25% less gain than a 12AX7 ECC83 Type. The USA made items have 30% less gain than a typical 12AX7 ECC83. To that is why we call it High gain, It is as close as you can get to the USA at a third of the price.

The Harma 5751 STR has been developed in direct response to the guitarists who want to reduce the distortion and gain level of their amplifier with sacrificing their tone.

The 5751 STR provides one of the most neutral and clear sounds of all the current production 5751 with the added bonus of a little more gain. It is very well balanced with nice even bass which has plenty of depth. The mid-range is very transparent and the treble has nice open chime.

This valve has a multitude of uses, firstly In the V1 position it a great choice for reducing the gain and the input position a cleaner and clearer sound. In this position it will also reduce the harshness found in some modern amplifier. In modern high gain circuits it will also reduce the fizz and hardness without comprising the gain.

All Harma preamp valves are Dynamically Drive tested under real working condition have passed the following tests:

Gain (db) Drive Tested)
Transconductance (gm) Drive Tested
Output Drive Tested
Noise 1 (signal to noise)
Noise 2 (Aural)
Microphonics Test 1(Ambient)
Microphonic Test 2 (Shock)
Cathode Test
Grid Leakage Test



Facebook Twitter Follow us on Instagram