[Scarydog]

Justin recommended I try this for my Amperex Bugle Boy ECC81:
https://www.ebay.com/itm/384447053179

Noticed my input tube is very sensitive to RFI nearby. He also recommended some weights to put on top of the transformer housing in case of transformer hum...

Interesting. I will try that!

Also wondering about how the rca and xlr inputs work on the back of the nautilus.

Would it be ok to have my Dac plugged into one and the turntable into the other?

Would having both playing at the same time (accidentally) damage the amp?

 

[DenverW]

So there are tube shields for 12au7 type, but I can’t seem to locate any for octal 6sn7 type? I’m curious if it will help a potential signal I’m picking up; i get intermittent high pitched sounds.

 

[ampsandsound]

Interesting. I will try that!

Also wondering about how the rca and xlr inputs work on the back of the nautilus.

Would it be ok to have my Dac plugged into one and the turntable into the other?

Would having both playing at the same time (accidentally) damage the amp?

Won’t hurt it but should only have one hooked up or the other. Xlr goes through the input transformers, rca is straight through.

 

[nwavesailor]

A nice chicken wire (spray painted black). faraday cage should go nicely over the single 6SN7 and BB..

I assembled one with wire ties for my first Garage 1217 amp and it did the trick!

 

[DenverW]

A nice chicken wire (spray painted black). faraday cage should go nicely over the single 6SN7 and BB..

I assembled one with wire ties for my first Garage 1217 amp and it did the trick!

Well, I'm investigating. What I thought was an issue with the 6sn7 may actually be a tube going bad on my audio mirror dac. I've swapped it out this afternoon and so far so good. Sometimes it would take 20 minutes or so to show up, but I'm feeling confident that I've identified the issue. I had been trying to identify the tube on the amp that was having a problem...possibly looking at the wrong source!

 

[nwavesailor]

It sound like you found the bad actor!

Here was my Faraday cage.............

 

[duranxv]

Won’t hurt it but should only have one hooked up or the other. Xlr goes through the input transformers, rca is straight through.

Do you recommend using the RCA or XLR inputs in general for the Nautilus?

 

[ampsandsound]

Different sounds. Depends on what your dac is doing

 

[theveterans]

Different sounds. Depends on what your dac is doing

Agreed! A great amp lets the DAC take authority/influence to the sound rather than let the amp gloss over the DAC

 

[Little Bear]

Agreed! A great amp lets the DAC take authority/influence to the sound rather than let the amp gloss over the DAC

If I understand your meaning, it makes no sense to me. The whole point of a tube amp is to impart a euphonic coloration to the sound. If you want to "hear the DAC" instead, then you need the most neutral solid state amp you can find.

 

[ampsandsound]

Different sounds. Depends on what your dac is doing

What I meant specifically was that the RCA is best suited to a single ended signal. Many balanced dacs sound best outputting in balanced/xlr and thusly the xlr input should be used. Obvious personal preferences matter most but that’s the general guidance.

 

[theveterans]

If I understand your meaning, it makes no sense to me. The whole point of a tube amp is to impart a euphonic coloration to the sound. If you want to "hear the DAC" instead, then you need the most neutral solid state amp you can find.

That's the conclusion that I personally experienced when demoing different DAC and amp combinations. A great tube and solid state amp EASILY lets you hear the DAC through the system more than those "neutral" 0.000000x THD amps out there where they impose their own signature rather than the DAC itself

 

[keithc]

@duranvx if I can help clarify, the Nautilus is unique since its RCA input does not use the input transformer, while the XLR inputs do. There is a tonal and interpretative difference w/ the music across both; I did not notice the RCA being any noisier or having a technical disadvantage, but rather, for my music, I found the XLR/input transformer sound was slightly more enjoyable to me. BOTH are great, just depends on your preference.

 

[paradoxper]

If I understand your meaning, it makes no sense to me. The whole point of a tube amp is to impart a euphonic coloration to the sound. If you want to "hear the DAC" instead, then you need the most neutral solid state amp you can find.

No. You also need a tube DAC to fully realize.

 

[Little Bear]

No. You also need a tube DAC to fully realize.

LOL. Fully realize what? I don't think either one of us understands his post.