[CADCAM]

Strange thing happened, I put the Svetlana back in and it is buzzing again where before it had been quiet. Not sure if it could be some outside source that's making the amp buzz.
Need to look into this further...

 

[Cyberthingy]

Strange thing happened, I put the Svetlana back in and it is buzzing again where before it had been quiet. Not sure if it could be some outside source that's making the amp buzz.
Need to look into this further...

I am slowly learning that once you get a configuration that works well that you don't keep messing with it when it comes to tube amps. Maybe the high end (expensive) amps are more stable but the Darkvoice and Monolith amps seem to be a little erratic with tube swaps. Maybe it has to do with secure seating of the tubes? I don't know, but they can be fickle beasts.

 

[CADCAM]

I am slowly learning that once you get a configuration that works well that you don't keep messing with it when it comes to tube amps. Maybe the high end (expensive) amps are more stable but the Darkvoice and Monolith amps seem to be a little erratic with tube swaps. Maybe it has to do with secure seating of the tubes? I don't know, but they can be fickle beasts.

Very good advise my friend, I put the first 6N3P tubes back in that I loved the sound of and the CEI 6080 back in and it's bliss!
No extraneous noises, beautiful detail and texture. Bass is absolutely fantastic and that tube character in the highs is ever present, smooth smoky mids too!

 

[CADCAM]

Just a quick update as I've been rolling some tubes into this with mixed results mostly good though.
I ordered 6 pair of different 6N3P tubes and several different 6080\6AS7G to try.
I'm in process but this amp is fine for tube rolling, it's built like a tank and the tube sockets are solid. No issue swapping out tubes. My only real problems were a gassy Svetlana and a noisy RCA 6AS7G. I'm trying to take notes so I can remember what sounded like what and I'll post my opinions when I'm finished but this takes up some serious time!
So far though my CEI 6080 sounds best to my ears but I have a 55' Sylvania Gold Brand on the way...

 

[Cyberthingy]

Just a quick update as I've been rolling some tubes into this with mixed results mostly good though.
I ordered 6 pair of different 6N3P tubes and several different 6080\6AS7G to try.
I'm in process but this amp is fine for tube rolling, it's built like a tank and the tube sockets are solid. No issue swapping out tubes. My only real problems were a gassy Svetlana and a noisy RCA 6AS7G. I'm trying to take notes so I can remember what sounded like what and I'll post my opinions when I'm finished but this takes up some serious time!
So far though my CEI 6080 sounds best to my ears but I have a 55' Sylvania Gold Brand on the way...

I have left mine alone recently. I swap back and forth between the Darkvoice and Monolith amps as I enjoy them both a lot. I still give a slight edge to the Monolith sound wise but the Darkvoice is much cooler looking with the exposed tubes. I wish I were a bit more industrious and creative to come up with a way to modify the Monolith case in a way to expose the tubes.

 

[CADCAM]

I think I may have just solved an issue with my Monoprice Monolith amp that I've had since I purchased it. It seems very well built and tube rolling hasn't been an issue. Tube sockets are secure and well mounted, I wish the tubes were visible but can't do anything about that. The issue is the volume pot. It's super sensitive, thank God for the impedance selection switch or I'd be in more trouble. Usable maybe to 9 o'clock even with my 600 ohm Beyers. Just gets too loud too quick.
I used to vertically bi-amp my speakers with twin McCormack dna .5's but have sold the speakers and amps off recently. The only thing left over from that system is a Placette RVC which uses a ladder array of vishay resistors to precisely control volume with 125 steps. I'm thinking if I put the Placette in between my DAC and the amp to control volume I'll have a little more adjustment & wiggle room.

 

[CADCAM]

I randomly purchased a CEI 6080 tube for this amp and it ends up being my favorite tube yet! Great detail in the top end and excellent bass as well as smooth textured mids.
I've tried several other tubes with varying results, some I like but are a bit noisy so obviously they are problematic when trying to do any critical listening.
I read an article that said cleaning the pins can solve some noise issues so I brought two of the tubes that were giving me problems into work and cleaned them with some fine emery paper under a microscope. One tube, a CEI 6080 backup I had bought was basically unlistenable but after cleaning the pins (which looked pretty good to begin with) the noise was down I'd say at least 60%! I ended up listening to that tube all night last night and never felt like I had to swap it out. The other tube I cleaned is an RCA 6AS7G that was really buzzing and\or humming and tonight I'll see how that works out. At any rate even if your tube pins look clean try cleaning them to further increase sq or get rid of noise problems.
I'll post on how I make out with the RCA later and today I brought my GE 5 Star and Sylvania GB 6080 into work! Let the cleaning begin...

 

[CADCAM]

Yea, pin cleaning is super important. I've spent the last few days cleaning pins on a bunch of tubes and the effect has always been extremely positive. One tube in particular, a GE 5 Star 6080 sounds so dam good now and it's really impressive in the Monolith. I'm using my Beyer DT990 600ohm cans with a Keces DA-131.1 DAC. Bass is just so badass. Mids and highs are also very enjoyable and you just don't get this out of SS equipment.
Cleaning pins is like having a picture behind a piece of glass and you just clean the glass so you can appreciate the picture more clearly. Now go clean some pins!

 

[Cyberthingy]

Yea, pin cleaning is super important. I've spent the last few days cleaning pins on a bunch of tubes and the effect has always been extremely positive. One tube in particular, a GE 5 Star 6080 sounds so dam good now and it's really impressive in the Monolith. I'm using my Beyer DT990 600ohm cans with a Keces DA-131.1 DAC. Bass is just so badass. Mids and highs are also very enjoyable and you just don't get this out of SS equipment.
Cleaning pins is like having a picture behind a piece of glass and you just clean the glass so you can appreciate the picture more clearly. Now go clean some pins!

OK, you convinced me. I'll give it a go this evening.

 

[CADCAM]

Cyberthingy how did the pin cleaning work out for you? Any improvements with noise and sq? I've been cleaning all my pins before swapping tubes and I think it makes a noticeable improvement.
Also picked up a 1977 Raytheon 6080 and am impressed by the sound, only gave it a quick listen but what I heard I liked alot. Hopefully after some serious listening sessions I'll affirm my initial impressions!

 

[Cyberthingy]

Cyberthingy how did the pin cleaning work out for you? Any improvements with noise and sq? I've been cleaning all my pins before swapping tubes and I think it makes a noticeable improvement.
Also picked up a 1977 Raytheon 6080 and am impressed by the sound, only gave it a quick listen but what I heard I liked alot. Hopefully after some serious listening sessions I'll affirm my initial impressions!

I finally cleaned off the pins of a variety of tubes but I really found that the pins on most tubes were already very clean. I did have a couple that had some mild oxidation. I used a product called Deoxit D5 which is used to clean contacts on switches and knobs. I had read posts on another forum that using steel wool on the pins was not a sound idea as little bits of the wool could be left behind and potentially create an issue. Bottom line is I found no improvements but then again the current tubes I am using were already performing well. I may try some additional tube swapping with tubes that may have been suspect previously but I am fairly certain they were underperforming because of their age or poor quality.

 

[CADCAM]

I finally cleaned off the pins of a variety of tubes but I really found that the pins on most tubes were already very clean. I did have a couple that had some mild oxidation. I used a product called Deoxit D5 which is used to clean contacts on switches and knobs. I had read posts on another forum that using steel wool on the pins was not a sound idea as little bits of the wool could be left behind and potentially create an issue. Bottom line is I found no improvements but then again the current tubes I am using were already performing well. I may try some additional tube swapping with tubes that may have been suspect previously but I am fairly certain they were underperforming because of their age or poor quality.

I used a fine emery paper and worked them under a microscope. My pins also looked to be clean but under the scope I was able to see discoloration and on some a coating of something perhaps oxidation on the pins. All my tubes benefited greatly from the cleaning process which unfortunately is tedious and time consuming.
To bad the contact clearer didn't result in any benefits.
I agree it's tough to tell if a tube is performing at optimum levels without a tube tester. Right now I'm running a Raytheon 6080 with great results in the Monolith.

 

[CADCAM]

Bought a pair of Svetlana 6H5C tubes last June on fleabay and one was super noisy and the other buzzed so I contacted the seller and they said replacements were on the way (from the Ukraine).
Got them in today! Seven months...not too bad! Anywho one is dated 1965 and the other 1966, tossed the 65 in and I like it...a lot, super quiet with my 600ohm Beyers to my 32ohm Monoprice Retro's. Bass and mids are fantastic, high end can be ever so slightly off a bit IMHO but the tubes are NOS from 1965 so I'll give it a few days to burn-in but already sounds so so nice! They look pristine which is a plus.

 

[CADCAM]

OK quick update if anyone is still listening out there.
The 1965 6N5S\6H5C power tube and a pair of 6N3P drivers from 1969 are in and sounding excellent right now. This is a great amp btw and zero regrets purchasing it! It seems if a chance to listen comes up (most of the time) I pick this system out of the three headphone setups I have at the house... so that says something right there.
Wish the tubes were exposed but the monolithic slab design is growing on me...

 

[Cyberthingy]

Great to hear you having success with the Monolith. I never switched away from the GE 5670W and Mullard 6080 because I like them so much. I'm very happy with the combo. I have not been listening to it much these last couple months because I purchased a Gustard X16 Dac and H16 Amp stack and they have garnered most of my attention in addition to a few new sets of IEMs. I also came down with the Covid then Pneumonia in February all while we dealt with that brutal winter storm. February was a bitch. This amp is a gem if you get a good one. I have found it plays nicely with most Planars which my Darkvoice does not do. I just got in a pair of Gold Planar GL2000 headphones I need to try with it. I'll report back once I do.