Acme 805 is a fantastic tube for LM 508 with excellent transparency and details. Serious owner of LM508 should consider getting one. The only catch is that it can sound hot in bright system. But it is taking strange turns, I am back to my 15 years old Silbatone 300B SET and it sounds more refined than retubed LM 508 although it has less headroom with 8W. Silbatone Acoustics JI-300B Integrated Amplifier Review By Steven R. Rochlin Also Shuguang Treasure 300B-Z is a steal with excellent soundstage and lively treble. Shuguang Treasure 300B-Z vacuum tubes Best Matched
I'll be back listening to my system against after the 31st so I will post impressions then. I am very curious as to the impact as I have heard both sides of the spectrum (some say very little difference/subtle at best and some say it was one of the biggest difference makers from a tube rolling perspective). I have a few things I have to do with the system so I'll have to do them one by one to hear the differences... 805 Psvane Acme tubes, 300B XLS tubes, Clear Day Double Shotgun speaker cables, DAC firmware update. Going to be fun
I compared WE original 300B made in 1930's with Shugang Treasure 300B in Silbatone 300B SET which is a world class amplifier with silver foil output transformer, oil cap, silver terminal. Silbatone Acoustics JI-300B Integrated Amplifier Review By Steven R. Rochlin The result is simple and but surprising. WE original 300B is more excellent in every way, nuanced details, wide , deep sounstage, tight bass and utmost transparency. But Shugang Treasure approach to WE original in every way more than 80% especially with soundstage. WE original 300B made in 1930's cost 5K$ or more. But Shuguang Treasure 300B-Z costs less than 300$ including shipping to US. Shuguang Treasure 300B-Z vacuum tubes Best Matched Thus it is a steal for the money. Now the only question is reliability. WE original 300B lasts more than 20K hours unless it is driven too hard. But who can tell reliability of Shuguang Treasure 300B-Z, although it is well built and looks much better than its price.
Not sure about the 300B's but I am getting the Don Sach's preamp which is coming with a quad set of Shugaung Black Treasure CV181's. Supposedly they are brilliant sounding on that amp and have good reliability.
I am running Shugaung Black Treasure CV181 tubes in place of 6sn7 in LM508. They sound organic and transparent but with some grain which may be gone when they are broken in ( I had run them only 80 hours or so). But I am pretty sure that they will not last as long as NOS tubes like Sylvania 1944. As long as they last 2000 hrs or more I will feel fine.
Have no experience with CV181 tubes. But, I would assume that they are similar to 6SN7's. I have two 6SN7 tubes in my preamp, which I was leaving on 24/7, since 2013 I have only replaced the tubes one time, with a pair of NOS Russian military surplus tubes, which I bought for about $18/pair on eBay. I'm getting the impression that these type of tubes last almost forever. I'm guessing that the 2nd set has lasted at least for 26,000 hours and maybe more, as I don't remember when I changed out the first pair of tubes. I am thinking that you will get your 2,000 hours out of them, plus a lot more!
Most NOS tubes were made for military use so they are reliable. But unfortunately, modern tubes are not. The chance is that I will replace Shugaung Black Treasure CV181 with another one before it run out of its life.
True, but most modern signal tubes will last 2,000 hours. Of course ones made for the military or NOS tubes will last far longer.
I would give the Acme 805s significantly long break in allowance before making a judgement on them. If they are anything like the Psvane 805ATs, they'll need a good amount of time. I rashly gave up on mine only to retry them later and find them more conducive.
Cossor Valve is also made in Psvane. But it is newer product than 805At. Acme 805 is another league above Cossor. It is much more transparent with lot of details. It did not sound too hot fresh out of box in my system. But it could sound hot in bright system due to to much details. On the other hand, Cossor is rather forgiving with pleasant sound and so excellent value for the price. Cossor will be better choice for bright system. COSSOR VALVE 805 made by PSVANE Hi-end Vacuum tube
that's interesting. i'm getting my 805 acme tommorow. the product description claims that the sound will get warmer and steadier using the acme series: "In the Acme Series, we have a number of patents,and also write a new chapter in our audio vacuum tube field: The very first style of high-power vacuum tube (Acme 845, 805, 211, etc.)with composite metal mesh screen pole structure in the world, graphite and metal wire mesh combined skillfully, make the sound very warm and transparent.Even at 600℃ temperature , the stress and thermal expansion coefficients of the two materials are in harmony, not only the sound is very steady, but also the power reserve and service life are also greatly increased"
I have only 60 hours on Acme 805 so it need to be broken in. But my impression so far is that it is not in the warm side, although it did not sound too hot. The transparency and details of Acme tube is top notch. On the other hand, Cossor is slightly warn and veiled compared with Acme tube.
i agree it is important to mention these tubes are physically higher, so the tube cage would not fully close.
I really want to reiterate what I said regarding break in. I completely gave up on the 805ATs because they were extremely strident during break-in to the point where I stopped using them thinking they should have been way past their break-in phase. I was wrong. Now they are extremely resolving compared to the stock tubes but just as warm in their presentation and actually more full bodied with bigger images.
Have any of you extended the height of the stock cage on your Line Magnetic amp? Any retrofitted adaptors work at "increasing the height" of the cage? It sounds like the new 805's will result in the cage touching the tube which is a no go so I'm curious if there is a workaround.
Same here. In the thread, somebody MacGuyvered a double banana plug setup but the pics don't show up anymore.
i tried to loose up the pins on the cage to their max but it's not enough, these tubes are very high. i'm thinking maybe putting metal spacers between the pins and the cage and using some epoxy glue to bond them. in this way it will look more asthetic and original i think. personally, i didn't like the double banana look.
Hi guys, I've read in this thread reports of improved sound quality when adding a separate preamp to the 508. Is this only true for preamps of a certain caliber? I have an Aric 6SN7 preamp that I'd like to try, is there a way to identify if it's better than the integrated one in the 508? More importantly, is there a confirmed consensus on which tubes the Pre In input bypasses and which remains in the signal path? The reason I ask is I only have one pair of NOS 6SN7 tubes, if those tubes are not in the signal path, I can move them to the preamp to maximize that component. Any thoughts?
I had decided on a Don Sach's Model 2 preamp to try. Unfortunately, due to some damage during shipping, I won't be able to give this experiment a try. Haven't even tried plugging it in due to fear of damaging it more.
Hello divertiti, According to James at Line Magnetic, using the Pre In feature does not bypass either the 6SL7 input tube or the 6SN7 preamp gain stage. The only thing bypassed when you use Pre In is the volume control on the LM 508ia. So you can't pull the 6SN7s.
On another note though, the 300B XLS switch has maybe made the midrange a tad smoother and the background a bit quieter but I am really stretching to hear the differences between these and the stock 300B's. Not too disappointed as this gives me a backup for my 300B anyway but it would have been nice to hear a clear, audible difference.
I heard the same differences on my end but they were more pronounced than what you experienced. Bought mine used so the price was lower but it's still quite expensive and the difference, in contrast to changing the preamp tubes, was relatively minor. Every bit helps in improving the SQ but considering the price of these monsters, a dramatic difference would've been appreciated, I agree.
Agreed on your last point. That's the point of this journey I guess As long as we enjoy the music from our setup, that's the goal. Still though, if I am being honest, I struggle to hear an obvious difference with new 300B's in place for my 805ia. Subtle difference, yes. Lowering of noise floor, smooth midrange while retaining dynamics of the existing sound, yes. Immediate differences to my ears? Not really. I agree, I heard a much bigger difference in changing the preamp tubes. I will be trying the new 805's tonight. Will see how they sound as they just start to break in over the weekend.
