Recommendation for a tube pre

[MattyW]

Hey guys, have had a few drinks tonight and had an original thought. I’ve avoided tubes in my system as it’s used by family and it can be left on for 8 hours or longer with nothing playing. A big no no for tubes (cathode poisoning).

 

I just now wondered, does anyone make a DHT tube (or 6SN7) preamp where it will power down after a period of time with no input? If such a thing exists that could fill my list for tube sound in my system without need to worry about tubes prematurely dying.

 

 Feel free to mention any product available anywhere globally at any price up to a maximum of $6k (inclusive of import duties and tax).

 

 Much as I love my icon 4PRO I still prefer the sound of my 3A5 DHT pre (Blue Velvet circuit) which has had a full recap, low mass RCA’s, wiring changed for solid core copper and EIZZ AMRS 24 step attenuator. Tubes still have an undefinable magic which no solid state pre can match.

 

Please note that the pre needs to be very quiet in terms of noise. I’m running 103.3db sensitive speakers so low noise is a must.

 

 Thanks in advance guys

Edited December 26, 2023 by MattyW

[rocky500]

How about some sort of timers that are set to turn off at a time that you normally would of finished listening to music?

You would need one for the amp to turn off first, then one for the Tube preamp.

[MattyW]

Nah, I’d be after something which just switches the circuit off after 30 minutes of no signal. I don’t know if such a beast exists though. I figure it’s worth asking about at least. I can’t be the only one with such concerns about tube life and such feature would be fantastic for anyone really.

Edited December 26, 2023 by MattyW

[muon*]

What you need is something with separate heater and B+ switches, that switches off the B+ after a time of no signal. Not sure if something exists like that, normally you need to switch off B+ manually and back on manually.

[MattyW]

Yes, that sounds like what I’m after.

[MTL]

@MattyWSchiit Freya + seems to fit your requirements

Mark

[MattyW]

Any other suggestions?

[MTL]

McIntosh c8 but is a little over your budget initially stated

[xlr8or]

I have many suggestions but none will fit your requirements. I'd personally ask someone like Earle to build you a custom WA unit that switches off the B+ and heater supply when there is no active signal present. I also know of others internationally that can do the same. The challenge though is the wait time for producing such a unit. Then you have the likes of the ARC LS28 and McIntosh C8 with auto shutdown features to consider but their costs, unless 2nd hand is also considered, are prohibitive relative to your available budget.

 

I personally don't believe cathode poisoning will result in your specific case, as I have studied the subject in great depth. You literally have to leave the amp on for a few weeks to get any initiation of it. And then if the tubes are continuously on they can always be replaced if they ever need any replacing in the first place. Preamp tubes last a very very long time.

 

I also think by considering such an option you're limiting yourself greatly to a compromise in tube preamp options and their resulting tonal characteristics. If your 3A5 DHT preamp already sounds good then just let it be.

 

I also have a young family and my octals, novals, and UX4's always get left on unintentionally. I've not seen any cathode poisoning result even after my amps have been left on for 7 days at a time unattended.

Edited December 27, 2023 by xlr8or

[MattyW]

Hmmm, I think that’s the best idea yet. I may see if I can get in touch with Earle.

 

His gear is gorgeous too. The Time  Machine Preamp looks to be a good choice.

Edited December 27, 2023 by MattyW

[rocky500]

Not sure if I should own up to this ..... but I have not turned off my Tube Preamp for years.

 

I think it is more of a hybrid than a pure tube preamp.

 

Edited December 27, 2023 by rocky500

[aussievintage]

15 hours ago, xlr8or said:

And then if the tubes are continuously on they can always be replaced if they ever need any replacing in the first place. Preamp tubes last a very very long time.

 

Yes, the only reason for a device that turns the preamp off, is to save electricity.

[MattyW]

I’m thinking Weston Acoustics Time Machine using a remote controlled AMRG resistor ladder for attenuation, Duelund Cast or Jupiter Copper Foil caps in critical locations, EIZZ EZ301 gold plated copper binding posts and Aeco ARJ-4045G RCA sockets would be the go.

 

I can try it as both an integrated amp and as a pre given my speakers are 103.3db sensitive. They don’t need high wattage. Course of the 2A3 tubes are only in the chain when using as an integrated then I may as well go lower down the range.

[Allan]

Supratek!

 

Australian made in WA, world renown and for good reason. I run the Supratek Cabernet 6SN7 into a Mark Levinson amp, its whisper quiet and sounds glorious, I love it... as do those who've heard it.

 

Mick who owns Supratek is very obliging when it comes to customer wants and maybe able to help with a custom timer. He does a DH Triode preamp, give him a call

 

https://www.supratek.com.au

 

 

Edited February 8, 2024 by Allan