I noticed an Elite moly 805 Linlai is due out soon... along with a Linlai Elite 6sn7.
Premium Vacuum Tubes link
Premium Vacuum Tubes link
Finally arrived. It has been expensive... and a veery long journey...
... working. First impression is good. These are pretty bright when glowing...
I have asked Lampizator (Lukasz) to make a small mod to my Wavac monos, so that top cap cable is repointed to the anode leg in the socket.
By doing so options for new production 805 tubes are multiple. With anode cap on top, it is very limited which 805s can be used.
Psvane used to produce fantastic 805 T-Reference series, but these are stopped now for the last couple of years.
When it comes to 805 without a cap choice is pretty wide with: Shuguang (few models), Full Music (lot of cool models), Psvane (regular and acme), Linlai (regular, DG, and Elite coming in the future).
I hope that Linlai DG-805 is similar to old T-Reference series. Price is not insane, contrary to ACME.
By doing so options for new production 805 tubes are multiple. With anode cap on top, it is very limited which 805s can be used.
Psvane used to produce fantastic 805 T-Reference series, but these are stopped now for the last couple of years.
When it comes to 805 without a cap choice is pretty wide with: Shuguang (few models), Full Music (lot of cool models), Psvane (regular and acme), Linlai (regular, DG, and Elite coming in the future).
I hope that Linlai DG-805 is similar to old T-Reference series. Price is not insane, contrary to ACME.
Stating the obvious but seems it is not tubes that are the issue here
It is an issue with new premium tubes. A 845 tube is specified to a performance level. Non of the new tubes are actually 845. They fit the socket and can take the voltage, but they can not take the current. You have to have an amp that is designed around a bias of 65 ma. That is not a requirement for a true 845 tube. A true 845 tube should run at 98 ma all day long.
Now I agree it is a problem with the amp because the amp I have is designed for a real 845 tube. One that handles 98 ma. I have already had the bias backed off to 88 ma. I will have to have it backed off again. The amp has a switch that puts another resistor in series with the stock bias resistor. As I switch in additional resistance and drop the current, piano notes start to loose a little punch. Loose a little speed and impact. They loose a little bit of realism to the instruments. I am concerned once I have the amp dialed back far enough that these, not so true an 845 tube, will become too flat and make the amp nothing special to enjoy. I guess only time will tell. My tech is purchasing parts to make the adjustment.
Now I agree it is a problem with the amp because the amp I have is designed for a real 845 tube. One that handles 98 ma. I have already had the bias backed off to 88 ma. I will have to have it backed off again. The amp has a switch that puts another resistor in series with the stock bias resistor. As I switch in additional resistance and drop the current, piano notes start to loose a little punch. Loose a little speed and impact. They loose a little bit of realism to the instruments. I am concerned once I have the amp dialed back far enough that these, not so true an 845 tube, will become too flat and make the amp nothing special to enjoy. I guess only time will tell. My tech is purchasing parts to make the adjustment.
On a different note: seems Elite 805 from Linlai can be purchased already:
www.hifi-amplifiers.com
LINLAITUBE Elite Series E-805 Hi-end Vacuum Tube Electronic valve Matched Pair [LINLAITUBE Elite Series E-805] - $539.99 USD
LINLAITUBE Elite Series E-805 Hi-end Vacuum Tube Electronic valve Matched Pair [LINLAITUBE Elite Series E-805]
Man Kingrex what a drag. I've been watching your progress and waiting to hear your tube reviews. I'm surprised the Wavac's run that hot. They are modern 845 amps and when built nos 845s were already unobtanium prices. What tubes were you running prior to these experiments?
If one is determined to buy Acme tubes right now I would recommend considering GD-Parts on Ali Express. They appear to be the only official online dealer of Psvane tubes with an online store. With the loss of Grant Fidelity GD-Parts has raised their prices to match GF's old prices. The caveat here is they offer a 24 month warranty. For whatever that's worth, mind you. Kingrex's experience aside there are quite a few reports of the Acme 845 red plating in "properly" biased amplifiers. The thing to note is it often the case that only one of a pair will redplate pointing to QC issues. You are going to want to buy from a dealer who will honor this as a warranty issue. Grant Fidelity would do this. Unfortunately Psvane has taken the position that red plating in the Acme 845 mesh portion of the plate is part of normal operation. I have an email into GD-Parts to get their take on the Acme 845 warranty. I will share their response here.
You are right about what Psvane says about the red plating. I bought a pair from tubeampdoctor in Germany and at the description it says:
"Note from Manufacturer:
Based on the design of composite metal screen, the anode will be slightly reddish in operation. This is a normal phenomenon.
It takes at least 50 hours for the sound to gradually stabilize and it may take 150 hours or more to reach the state of perfection."
Here is the link: tubeampdoctor 845 ACME
I have Audion Black Shadow, not a Wavac. Mine are 19 years old. But they were just rebuilt by the official US importers technician. They should be operating per the design.
My comments about an 845 tube are based upon what my tech was saying to me. He remembers the day you went to the grocery store and there was a tube tester there. You could test your tubes and purchase groceries in one stop.
He says the old USA tubes were built much better than the remakes. He was speculating a portion of the reason is how small the tube market is today. Not many are sold. If they made a tube that lasted for 10,000 hours, they would sell to few to be a viable product. I'm noting that this is pure speculation.
And if I were to have a choice between the Psvane and LinLai, well I personally like warm and fat. I could live with the small squares glowing a little and see how ling they last. If I got over 2000 hours I would begin to be satisfied. But I had KT88 in a CJ Premier 140 and with 2000 hours they sounded almost identical to a brand new set. Only a touch more smooth. I would like my 845 to have similar durability.
Attached is the spec on my Elrogs.
He says the old USA tubes were built much better than the remakes. He was speculating a portion of the reason is how small the tube market is today. Not many are sold. If they made a tube that lasted for 10,000 hours, they would sell to few to be a viable product. I'm noting that this is pure speculation.
And if I were to have a choice between the Psvane and LinLai, well I personally like warm and fat. I could live with the small squares glowing a little and see how ling they last. If I got over 2000 hours I would begin to be satisfied. But I had KT88 in a CJ Premier 140 and with 2000 hours they sounded almost identical to a brand new set. Only a touch more smooth. I would like my 845 to have similar durability.
Attached is the spec on my Elrogs.
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If I'm reading the datasheet correctly (http://www.r-type.org/pdfs/845.pdf) at 1250V, the 845 is rated at 80mA in class A operation. Am I misunderstanding? Corrections welcome.
These are not the 'specs' of the Elrog ER845. This is the bias point which we use to match the tubes in the pairs. Specs are here: https://www.elrog.com/products/
Our tubes are rated for 100W max plate dissipation. If you run the tubes at that limit you might get some cherry red on the plates. if you run tubes like that the heat simply builds up and you will most likely also get some cherry red plates in old production tubes. BTW check the Amperex 845 data sheet: https://frank.pocnet.net/sheets/111/8/845.pdf
They rated them at 75W max for Class A amplifier service. Still it is a true 845 or not?
It is generally not a good idea to run your tubes right at the max rating. Drifts or mains voltage variations will then occasionally push the tubes beyond that limit. Not a good idea not only for new production tubes but also old US production. It is always better to stay clear of the max ratings if you want longest tube life
Best regards
Thomas
On a different note: seems Elite 805 from Linlai can be purchased already:
LINLAITUBE Elite Series E-805 Hi-end Vacuum Tube Electronic valve Matched Pair [LINLAITUBE Elite Series E-805] - $539.99 USD
LINLAITUBE Elite Series E-805 Hi-end Vacuum Tube Electronic valve Matched Pair [LINLAITUBE Elite Series E-805]
@JSA Wondering what your opinion is of the Linlai 805A-DG's is now that you have had them for a number of days. I tried a pair and unfortunately had to sell them. While the top-end was very nice and grain free, I simply found them far too lean. This seems to be in line with all reviews of LinLai vs Psvane so far. I went back to my stock Psvane 805 AT's until I get something else - either RCA VT-143's or ACME's I think.
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I'm still absorbing Thomas's comments. I looked at his spec and it says 1250 volt max plate dissipation 100 watts.
So what does that mean????? If a tube is still redplating at 88 watts, then what does 100 watts mean????? I thought plate dissipation meant it could shed the heat and not redplate with 100 watts. But thats not the case. Psvane, linlai and Elrog can't t even shed the heat at 88 watts. At 88 watts, a 1 to 2 volt swing of power at my house is not taking me anywhere near 100 watts.
So I'm feeling confused why do 845 tubes say they can dissipate 100 watts, but don't realy appear to be able too.
What is the bias on other peoples 845 amps?
So what does that mean????? If a tube is still redplating at 88 watts, then what does 100 watts mean????? I thought plate dissipation meant it could shed the heat and not redplate with 100 watts. But thats not the case. Psvane, linlai and Elrog can't t even shed the heat at 88 watts. At 88 watts, a 1 to 2 volt swing of power at my house is not taking me anywhere near 100 watts.
So I'm feeling confused why do 845 tubes say they can dissipate 100 watts, but don't realy appear to be able too.
What is the bias on other peoples 845 amps?
Hi Kingrex,
Well it means that the tube can handle that. if run at max dissipation a slight cherry red on the plate can occur visible when the room is dark. If you have more like an orange color on the plate visible at daylight you have more than 88 Watts dissipation. Can you share the exact voltages you have? grid voltage, plate voltage and cathode voltage (if auto bias) and/or plate current? I can replicate the same bias point on a tester and can show you how it is supposed to look.
Still 88W is an awful lot of dissipation and some of old production 845s were not designed for that. See also an excerpt form the RCA transmitting tube manual which also states 75W maximum dissipation for Class A audio service.
If you have different 845s with this behaviour it is a strong indication that it might not be the tubes. 88W is an awful lot of heat and added to that are the 32W of the filament which need to be dissipated. So how the tubes are installed in the amp, how close they are to other tubes or chassis sides will also play a role how far the tubes are heated up and if the plates show any color or not
Again I can only reiterate that some of the original old production 845s were not even designed for such use as the link to the data sheet and excerpt from the RCA manual prove. So I am puzzled why you keep questioning new 845s against old 845s. Have you tried an old production 845 and don't get the same color?
Best regards
Thomas
Well it means that the tube can handle that. if run at max dissipation a slight cherry red on the plate can occur visible when the room is dark. If you have more like an orange color on the plate visible at daylight you have more than 88 Watts dissipation. Can you share the exact voltages you have? grid voltage, plate voltage and cathode voltage (if auto bias) and/or plate current? I can replicate the same bias point on a tester and can show you how it is supposed to look.
Still 88W is an awful lot of dissipation and some of old production 845s were not designed for that. See also an excerpt form the RCA transmitting tube manual which also states 75W maximum dissipation for Class A audio service.
If you have different 845s with this behaviour it is a strong indication that it might not be the tubes. 88W is an awful lot of heat and added to that are the 32W of the filament which need to be dissipated. So how the tubes are installed in the amp, how close they are to other tubes or chassis sides will also play a role how far the tubes are heated up and if the plates show any color or not
Again I can only reiterate that some of the original old production 845s were not even designed for such use as the link to the data sheet and excerpt from the RCA manual prove. So I am puzzled why you keep questioning new 845s against old 845s. Have you tried an old production 845 and don't get the same color?
Best regards
Thomas
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Hi Thomas, i would have to ask my tech to take all the measurements. This is what I have seen
1100 93w
1200 87w Vp=967v Vk=124v
1250 85w
1500 74w
1750 67w Vp=1001v
2000 61w Vp=1011v
1000 98w
Right now I have the 1200 operating. I put the Elrog back in. At night under a dim light the plates are not really red from a distance. If you get up close and look you see the glow trying to break through. They are right at the tiping point.
If you have an image, it would be nice to see. It would help me to know my amp does not have isses.
1100 93w
1200 87w Vp=967v Vk=124v
1250 85w
1500 74w
1750 67w Vp=1001v
2000 61w Vp=1011v
1000 98w
Right now I have the 1200 operating. I put the Elrog back in. At night under a dim light the plates are not really red from a distance. If you get up close and look you see the glow trying to break through. They are right at the tiping point.
If you have an image, it would be nice to see. It would help me to know my amp does not have isses.
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