2015 should be a great year for everything, including Lampizating. LoLQuote:
Originally Posted by User211
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2015 should be a great year for everything, including Lampizating. LoLQuote:
Originally Posted by User211
Fully foo'd.
Golden Gate Big 7
Just discovered there is a manual for all Lampi DACs,
From that manual:
DHT triodes used in our Level7 and Big 7 DAC are yet another can of worms. Most
DHT tubes have the same base (four pin) and the same pinout (two fat legs are
heaters and cathode, two slim legs are Grid and Anode. The problem is that these
tubes have completely different heater demands. Our DAC7 is designed to accept
ALL KNOWN dht triodes from this group: 101D, 45, 245, 345, 6A3, 2A3, 300B.
People keep discovering more and more compatible triode types every month.
How is it possible to run so many triode types in one circuit ? DON’T THEY HAVE
DIFFERENT HEATERS ?
Our genius circuit automatically detects the current demand and adjusts voltage
accordingly. We added a switch which divides the tubes into two groups: high heaters
and low heaters. High heaters are 2A3, 300B, 6A3 and low heaters are 101D, 45, 245,
345.
Our favorite tubes are: (New) Sovtek and Electro Harmonics 2A3 - this is actually the
same tube but Sovtek is a cheaper brand.
45 by Emission Labs (New). 245 and 345 NOS from Sylvania, Tung-Sol and RCA.
101D by Psvane WE Replica (New). Nos 6A3 from any US brand. 300B Mesh Black
from Psvane.
User211 Stated:Later User211 Wrote:Quote:
They (the 6A3’s) are NOT good in the 2A3 position - they sound distorted. They go over the 6.2 Watts max I found out later - 6.5 I am told.
Later, User211 stated:Quote:
6A3 - don't try it in a 2A3 setup L7. It sounds distorted.
Because of the above posts, I used the 6A3's in the 45 switched position but wasn’t really happy with some stridency I heard in the upper frequency range. I later tried them in the 2A3 position and they sounded quite superb, substantially better than the much more expensive Emmission Labs 45’s that came with the DAC! However, when I listened to the system a day or 2 later, I was hearing objectionable distortion like User211 stated above -- distortion one time, the next NONE!Quote:
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.
However, in an even later post User211 provided a link to a “Manual” for all Lampi DAC’s (BTW, this was a valuable find; Lukasz did a wonderful job of providing information, not commonly found in Manuals. Kudos to Lukasz!)
From the manual, User211 provided the following:.Quote:
Our genius circuit automatically detects the current demand and adjusts voltage accordingly. We added a switch which divides the tubes into two groups: high heaters and low heaters. High heaters are 2A3, 300B, 6A3 and low heaters are 101D, 45, 245, 345.
This would suggest that the 6A3 should be run in the 2A3 switched positon. Which, based on my initial finding, sounded darn good!
But, since both I and User211 had a positive experience and then later, a distorted one, I’m wondering what the heck is going on?
Is the “genius circuit” not automatically detecting the current demand and adjusting according? Between sessions, I used my remote's Off button, to I assume, put the DAC in the standby mode. NOTE: I didn’t use the On/Off toggle in the back of the unit.
[BTW, as an aside, is this what everyone does between listening sessions: engage the front Lampi button, or in the case of using a remote, use its Off button, to put the unit in Standby?]
I wonder if using the remote's Off button one day and then its On button the next day, did something to cause the “genius circuit” to NOT adjust properly?
Ultimately however, should the 6A3 be run in the 2A3 positon and how can I get it to run undistorted, the way I first heard it? How are others running the 6A3 and is distortion ever a problem?
I think we need try and post results. I had a nine pcb b7 and niw a pcb they do act different to the same tubesQuote:
Originally Posted by Mrmb
This is a learning curve experience. We need to just try and post. Also there is taste here as well. I do remeber some times hearing distortion at times with some tubes. But consider the NOS factor as well there not new tubes. So as individuals they may act different. Just some thoughts to consider
Al
BTW Al, I've enjoyed your posts here and elsewhere, especially your "B7" comments and tube-rolling results.Quote:
Originally Posted by ALRAINBOW
I agree, there are many variables to consider. But when User211 expressed a similar distortion experience as mine, I found it somewhat coincidental, that our NOS 6A3's themselves, could be an issue. However, stranger things have happened.
At any rate, the sharing of additional tube rolling experiences (especially with 6A3's) was my post's goal and hopefully will result in a better understanding of what's going on and what tubes everyone is finding to be their preference in their Lampi 7's.
Cheers,
-Mike
Hi Mike,
I have been running 6A3 in the high heater position for a good long while. They have sounded fine and for some reason I have not heard the distortion I knew I heard before.
Anyway, on balance they are getting the most usage of all the triodes I have bought. They must therefore be my favourite. I am itching to try the more expensive Psvane 101D though.
One thing I am thinking could be a possibility is the 6A3s I have probably haven't been run for decades for any period of time, and the high heater just pushed them into a funny state. See what I said about the Raytheon rectifier being noisy for 5 minutes. Maybe they have just stabilised now? Who knows...
And yeah - better than smooth plate EML 45s by a long shot I think. For £60 odd quid:lol:
Hi User211, by "high heater", would that be with the 7’s toggle in the 45 position (i.e., not the 2A3) position?
I listened extensively today with the 6A3 in the 2A3 position. Simple, less complex music (e.g., Rebecca Pigeon/Spanish Harlem) sounds really good. More complex orchestral music &/or rock seems to become a little congested (maybe distorted?). I still remain firmly ensconced in the non-committal auditioning stage however....
As of yet, I haven’t rolled the Shuguang 274B rectifier, but am considering a WE422A or Mullard Metal Base 5AR4.
Obviously there are significant system and personal variables that affect judging whether one tube in our DAC tops another. However, rather than drop bucks on fairly expensive tubes that I will never use – i.e., NOS 2A3’s, NOS 245/345 Globes, NOS VT52’s, Psvane Replica 101D’s, etc., verses the EML 45’s that were shipped with my DAC, I’m wondering where I should go from the EML 45’s or the NOS Sylvania 6A3’s that I now own? I’m intrigued by the Psvane Replica 101d, but because of cost have some reservations! Suggestions/recommendations...??
See post #143 for heater description - so it is the opposite of what you have said.
I don't get any congestion with 6A3 no matter what the music type - complex or simple. Given the cost of the DAC $200 for a pair of triodes is small fry I think.
I also have the Psvane Hi-Fi series 300B on loan but it sounds so damn clean - like everything has been polished, literally, I don't like it. So that's not recommended by me at least. All I can suggest is that you read my descriptions of the triodes I have used and take your pick.
I'm back on VT-52 for the moment. I like to change but the three in most constant use are 6A3, Psvane 2A3 and VT-52. VT-52 is the most rolled off HF wise. It'd be interesting to see how close the "genius circuit" is getting to VT-52s supposed optimal running parameters. I'm betting it isn't that close. I still like it though:)