The supply of valves/tubes has been affected by the Ukraine conflict. 

Electronic valves made at the New Sensor facility in Saratov, Russia, are under export/import embargoes. Tung-Sol, Electro-Harmonix, EH Gold, Genalex Gold Lion, Mullard, Svetlana and Sovtek brands are all affected.

In a recent press release Mike Mathews, the owner of New Sensor, explained that the production of valves has been adversely affected by the Russian goods ban. “Given this export ban, we will not be receiving any further tube inventory for these brands,” explained Matthews in a statement released over the weekend. “A myriad of pressures – including continued strains on the supply chain, escalating internal expenses, mounting inflation, and an ever-evolving legal landscape (particularly in light of the Ukraine conflict) – have created a very fluid and ambiguous environment.”

Mathews went on to say that they won’t be shipping any more Russian tubes until the recently announced bans on exports are lifted – which is currently set to happen at the end of 2022.

Clearly, the supply of valves is a minor issue compared to the terrible suffering of the Ukrainian people, and hopefully there will be a return to some sort of normality soon. One would think that there is a large enough market for valves worldwide for another factory outside Russia (China or the US) to step up and meet the demand.

In the meantime, RedRoo builders will need to source non-Russian valves (JJ, ShuGuang, Psvane) or use the second-hand market (eBay). It's likely the supply of valves will be difficult in the short-term until non-Russian production ramps up to meet the demand.

The good news is that the RedRoo SE5 amplifier can be easily configured to use a variety of valves, as follows:

Preamplifier stage: 
Common types: 12AT7, ECC81, 6060, 12AX7, ECC83, 6DJ8

The most important parameter to look for is a heater-cathode breakdown voltage of greater than 120V, otherwise tube life may be affected. The high Vh-k is required for the cathode follower section of the CCDA input stage.

Other types that may work: 6201,6679, ECC81, 6201, 6671, 6679, 7492, 7728, A2900, 8152, B309, B739, CV4024, E81CC, ECC801, ECC801S, M8162, QA2406, QB309, 7025, 5761,6057,6681,7494,7729, 7025#, ECC83#, 6L13, 12DF7, 12DT7, 5751, 7025A, B339, B759, CV4004, E83CC, ECC803, M8137

ECC88, 6ES8#, 6ES8, ECC189, ECC189#, 6FW8, 6KN8, 6922, E88CC, CV2492

Output Stage:

Common types: EL34, 6CA7, KT66, KT77, KT88, 6V6, KT66, 6L6, 6550, 6V6, 6P6P, 6P3P, 

Other types that may work: 5881, 1622, 5932, 7581, 7581A, WT6, EL37

And with a socket adaptor - 6BQ5, EL84, 6P15 

If you require more information or assistance please contact us at  www.redrookits.com

Hopefully things will get better soon, especially for the Ukrainian people.
regards

Phil Wait
Sydney