I am considering upgrading the stock 300B. Anyone compare the Psvane ACME to the EML XLS ? Also there is new Linlai Elite in the market which Grant Fidelity is now selling.
I have the Q Acoustics Concept 500 floorstanders, wich are 6 ohm average with 3.8 ohm minimum. I find the 8 ohm binding post and NFB set on 4 in my LM-508 to sound the best by far. Alive, full bodied and incredibly holographic. I guess we all have to try and trust our ears. My amp has Robert Lai's internal upgrades, maybe that helps, I don't know.
By the way, I was using until yesterday the Sylvania 7F7 and for the last days I was feeling that something was missing. So I decided to try back my loved Sylvania 6SL7 WGT brown base (golden letters on the glass). Well, that's "the one", at least from my stock. It takes the LM-508 to a "whole" new level. I mean the 7F7 is a very nice tube, but the brown base has better everything: layering, 3D sound, resolution, transcients, tone, etc. It's not a night and day difference, but noticeable. It's going from "it's a very good tube" to "WOW, what is this". I haven't tried Mullards in the 6SL7 slot, but I've tried several well rewarded 6SL7 tubes and this one is incredible for the price, about 30 to 40 euros.
Does anyone know what size anode grid caps and wires to get for the RCA 805 ? I ordered the acme 300b and have a bunch of tubes coming in this week and next. Will post impression when I get a chance to run them in.
They're sold here. Ceramic top cap (LARGE SIZE) for 805 / 811A / 812A / 866A/ 872A (7 in stock) - Tube World Express
thanks @Strat-Mangler. Can you (or someone) also help with the wire and what connector is needed on the other end ?
Read here and continue to read for the next page or so if you want more details. New Line Magnetic 508ia Integrated Amp
Thanks, but I can run my Muraudio SP1s with a freakin' Advent 300 receiver and the high end is back. Not my hearing, it's the 508.
I see a number of folks here have been running the Psvane ACME 300B's ... but has anyone tried the Psvane WE 300B replica's? (both original and more recent Plus version).
A friend has a LM amp, though not this one. He really disliked them quite a bit. All mids and nothing else.
Only 13 hrs on them so far but the Psvane ACME 300B's have been more impressive than I expected. They have really fleshed out the sound without being muddy. Just so well balanced in all aspects. Sonic improvements across the board. That said, I was surprised that when I put them in the bias jumped to 140 ma ... had to bring it back down to 120. Which suggests that my stock tubes had really diminished over the past 14 months of use or that the ACME's run at different levels for same plate voltage? Unclear on that.
I also got the ACME 300b couple of days back and burning in. Will report back after having 100hrs or so but there is already an uptick from the stock. I noticed that there is a pop from the speakers after 2/3 secs from the power-on the amp. With the stock 300b, no such pop. Chris, do you have this issue ? On the different note, the 7F7 with the adapters sounds really great. Probably the quietest as well. Anyone tried 7N7 w/ adapter in the 6SN7 slot ?
@Devg no I have not noticed any pops with the ACMEs. I should probably withhold my observations until 50-100 hours myself but it was readily apparent in my case. Again I suspect that my original stock tubes have lost their edge a bit. Your amp is new right? yeah the 7F7 is the quietest tube I have had in the 6SL7 slot. I love it and have not bothered going back to the ECC35 or other tubes. What I would say about it is that is absolutely clean, neutral and does no harm - all other 6SL7’s I have tried have something that I don’t like. My two ECC35’s, while very musical, being muddy and noisy for example. Now waiting on my Psvane 805 ACME’s, at which point I will be running the two pairs of ACMEs, the mint early JAN-CHS 7F7 and a pair of possibly well worn ECC32’s (but they were relatively cheap and sound great).
Interesting. Mine pop'ed from the start I put the acme 300b replacing the stock. I replaced the acme 300b with the stock and there is no pop. Yes, the amp has probably around 300 hrs on it. Yeah, the acme 805 will be my next purchase. Did you purchase the acme from hifi-amplifiers ?
I had been quite since I had enjoyed almost infinite comination of tube rolling after having Schitt Freya + in front of LM 508. Schitt Freya is very effective to remove any remaining ground hum. It is good to hear that some guys are enjoying Psaven Acme 300b and 805 that I had introduced to this site 3 years ago. I also had collected more than 20 6f8g tubes (RCA, Sylvania, Tungsol. Raytheon, National Union, Zenith, etc). Although 1578 Melz is my first choice overall, other 6f8g tubes also give interesting flavors. It is also good to collect Nos 805 tubes before they are gone. I had collected more than 10 pairs of Nos 805 tubes which are almost as good as Acme 805 with different flavors. One advice to newbie of LM 508 or 805 is not to let amp on more than 2 hours to prevent deterioration of capacitors inside amp. Then you may be able to use LM 508 for more than 3 and half years (around 6000 hours so far) without big issue like me. Good luck to everybody.
How is this different from any other amp ? Are you talking about power supply caps or the coupling/electrolytic caps in the signal path ? Almost all amps with have capacitors in these forms. I have always read charging/discharging of capacitors cause more issues than not.
I can not answer your question. I also have Silbatone 300B amp which use more expensive caps. But I had to replace all caps inside it after using it for 6 k hours about 8 years ago. After that incident, I make it a rule to let the class A tube amp cool down for one hour at least after two hours of playing. It had worked.
just trying to understand - are you talking about tube amps in general or specifically about the 508/805 ?
@thomaskong you have prescribed this theory of hours before on here. There is no evidence that cooling down the LM amp after 2 hrs will prolong its life. If this was really the case no one would use tube amps. I certainly wouldn’t. btw, seeing as how you have spent thousands of dollars on rolling tubes including many 6F8G’s, its strange you have not tried out ECC32’s in the 6SN7 slots. .... you have a big hole missing in your stash ...
What you're saying (again) makes no sense. Caps can last decades. Your limited experience with one fluke situation doesn't make you wise about this stuff. It's just wholly incorrect to write this nonsense. 6K is nothing for a good cap.
There are some terrile and rude guys like Chris and Strat here. I have much more experience in tube amps than you guys. That is the reason that I had not written anything in this thread for a while. I have some useful information about 6f8g tubes but I will not write here. There are some overhyped and overpriced tubes. But you can enjoy nice sound out of reasonably priced tubes with careful selcetion. This will be my last comment here because of two terrible guys.
