Lampizator Level 7

[User211]

I have a few sets of the tubes. The adaptors I bought do not work. They are wired wrong. I intend to fix them soon. And report back. So far the leader for me is 6a3. But a friend who had my tubes a whole bunch feels the 300 B carbon just edged them out. And I truly trust his call. I have heard his set up and it's very clean and transparent. The improvement is minor but it's there.
I also have Elrogs coming and a few others.
At conclusion rolling tubes is a cheap way to change ones sound signature and is fun an rewarding. It allows me to set the mood if not explore sounds without breaking the bank.
Al

Yeah I hope the sockets last Al. Change of speaker means I'm evaluating them all again. Please post on the ELROGs I'm most interested.

[User211]

Some great reading going on over at the Wam.

I dunno where the assertion that a Big 7 costs £10K came from though. Mine cost £4K less than that. A new AN 4.1 is way over £10K.

Some good points/tempers flaring in classic Wam styleeee. No place like the Wam

I actually agree with some of the anti statements. When people speak their minds on topics they feel emotional about it really does get interesting.

[bonzo]

Some great reading going on over at the Wam.

I dunno where the assertion that a Big 7 costs £10K came from though. Mine cost £4K less than that. A new AN 4.1 is way over £10K.

Some good points/tempers flaring in classic Wam styleeee. No place like the Wam

I actually agree with some of the anti statements. When people speak their minds on topics they feel emotional about it really does get interesting.

I think 10k is the dollar figure

[User211]

Sounds about right but I did go cheap i.e. no DSD and 6X5 recti. But I have 274Bs in the preamp so boring to meet up with that again in a DAC. Besides, the 1950s Tungsram 6X5 is an absolute peach I am well happy with.

[_JL_]

I did some more tube rolling on my Lampi DAC 7. It's the two-box version but I have mod the filament supply voltage to allow more precise control of the voltage and with improved ripple performance.

Rectifier: 6x5
So far I tried the stock Russian 6x5 (coarse sound), Raytheon 6x5GT and Sylvania 6x5GT. I liked the Raytheon the best as it has the best balance between resolution and refinement. The Sylvania is too polite in comparison. Note it could be due to the samples I have as I'm not sure the ones I have are NOS or not.

Output Tube:
EH 2A3 - This is the stock tube and I found it to lack life and extensions. Not recommended.
Sovtek 2A3 - This one is a surprise as it sounds fairly good. Good extensions and resolutions. Not the ultimate in refinement but with incisive bite. Sounds best when run with low filament (1.8V vs 2.5V). Good value for money.
EML 45/45 Mesh - Refined but lacks some excitement. Note the 45s I have may be too used so newer tubes may sound better. Not recommended.
EML 2A3/2A3 Mesh - The solid plate 2A3 sounds more extended than the 45 and have better resolution. The mesh plate 2A3, however, is even better by a wide margin. It has the best balance and resolution, refined and yet lively. The mesh plate 2A3 is by far the best in my L7 by a wide margin. Highly recommended.

I'd still need to try some old stock 45 of which there are plenty of variants - even mesh plates. May also get some 6A3 and 101D (or even 205D) to try as well. This DAC is a tube-roller's dream as the output stage is so simple and the power supply is easy to mod.

Happy listening!

[_JL_]

An update - the Psvane 101D-L and 205D-L arrived. These tubes have 4.5v filament.

The 101D-L can be run under the 45 setting in my L7. The secret is the lower filament current (1A vs 1.5A for the 45) and this results in less voltage drop by the filament supply resistors, thus leading to higher than 2.5V actual filament voltage. It is still a bit low - ~3.9V in my L7. I also tried it with the 2A3 setting but the resultant voltage is too high at ~5V.

The 101D-L is running at ~11.5mA bias current in my L7. This is higher than the spec (9mA) so the tube is being run under high load conditions. Not sure if this will affect tube life in the long run. It's probably fine for the Psvane 101D but I certainly won't risk any WE 101D with this operating condition.

The 205D-L by comparison is designed for output stage so it works fine at such bias current. It draws 1.6A filament current so I have to run it at the 2A3 setting to arrive at ~4.4V filament voltage, which is about right for the 205D.

Now for the sound, my brief impression is that the 101D sounds better than the 205D, with more air, transparency, and life. Comparing to my current reference - EML 2A3 Mesh the 101D is more polite, less airy, and with less micro-details. So the EML 2A3 Mesh is still the best by far. Note that I have only run the 101D/205D for minutes so their sound may change upon further run-in.

The thing about the L7 is that the filament supply is not regulated and is tuned by dropping resistors. Thus I think it is a good idea to have a UX4 test adapter to check the actual operating conditions before running a new tube for the long run.

Happy new year everyone!

[User211]

Hi Jack - I'd be interested to know what you make of the 6A3. I tried it again in the 2A3 switch position and didn't hear the distortion I thought I did last time I tried it. Odd.

I think the only thing for a level 7 owner to do is stock up on about half a dozen triodes and then decide for themselves. Due to the cost of the DAC most owners will do this anyway as it is relatively small beer unless you decide to pay ridiculous premiums for valves that cannot possibly justify their price. At the end of the day systems and ears vary.

That said the most sensible short list of valves to try come from reading threads like this. The trouble is there are conflicts as people hear different things.

It is interesting that 101D came out better than 205D even though it was a less than optimal electrical match. Half the reason for the marked variance in sound when trying different valves in this DAC is that some will be operating at quite some distance from their supposed optimal settings.

I was at the 2008 HK Hi-Fi show when staying in Mongkok, Jack. Very nearly as good as Munich in terms of gear.

HNY.

Justin

[wisnon]

HNY Justin,

I dont know where you guys manage to find cheap VT52 tubes. i never seem to be able to find that. LoL

[hifinutt]

The MSB DACs were in a lot of rooms at Munich 2011. From what I can remember, they all sounded great. This was probably my fave room using one. Video shot by me.

I am a great fan of msb , using their power amp with superb results for quite a while now .

one day hope to try the msb dac but the lampi would also do nice

[User211]

HNY Justin,

I dont know where you guys manage to find cheap VT52 tubes. i never seem to be able to find that. LoL

Yo Norman I'll send you mine. Happy Lampizating New Year!!!