Aegis DIY Tube Headphone Amplifier

[DenverW]

Man, I haven't soldered anything in over a month. Perhaps it's time to start poking around with mods and 'upgrades.'

What little tweaks has everyone done? Anyone with bypass capacitors? Internal wiring change? Different electrolytic caps? Inquiring minds want to know!

 

[Toonartist]

The mods I’ve made so far are…

Furutech Rhodium IEC Inlet/socket

Neotech Solid core 20awg Teflon coated wiring throughout… except earth connections which were stranded.

Kemet first input cap for 274b rectifiers

Jupiter Silver Foil Comet Caps

Toroidal 4 amp transformer with resistors to balance heater supply for 5v 3amp & 2amp rectifiers. The 4amp rating should provide enough headroom for tubes demanding more than 3amp.

 

[martelanc24]

I have made some similar mods, full Neotech wiring, 4uF input capacitor, extra 5V/4A toroidal transformer, 12.000 hour electrolytic Rubycon capacitors for longevity,... I wrote about all this in detail in my post: https://www.head-fi.org/threads/aegis-diy-tube-headphone-amplifier.965530/post-18569233

1. I would go for the functionality expanding mods first. Both "cheap" and not super hard to do.
- The 4uF capacitor is a really easy mod and none of us found any problems with it.
- Adding a toroidal transformer for 3A rectifier tubes is more complicated in terms of mounting it and figuring out the optimal resistor value to stay close to 5V on 2A and 3A rectifiers.
But the downside for the above mods is you will then be looking at 274B and various 3A rectifiers.

2. Changing the Jupiter foil capacitors will change the sound, but for a high price, especially Jupiter Silver Foil Comet Caps.

3. The hardest mod, but adding even more functionality, would be the relay array board. You add one extra output impedance and a pre-amp out. But this means a massive rewire of the already assembled amp, drilling holes and figuring out how to mount the extra PCB.

That is the extent I went to. I haven't explored or have any wishes to mod the actual circuit of the amp, meaning changing component values, cutting traces on the PCB or things like that.

 

[DenverW]

This is an interesting looking little cap, but I don't believe the lead spacing will work, as it's 10mm from the data sheet, instead of 7.5mm.

https://partsconnexion.com/mundorf-...lar-radial/?searchid=583308&search_query=22uf

 

[Schuie Driver]

Hello fellow DIY Aegis builders/owners and @L0rdGwyn. First off, I'd like to just say that I am absolutely in love with the sound qualities of my DIY Aegis (built by @mchuckp) and this post is really just a plea for help/ideas as I've got one issue with mine that I can't seem to get rid of. What problem is that? Noise. Not a hum, but what sounds like a low level electrical noise or static. This CANNOT be heard while music is playing, but can be heard between tracks (but you do have to listen for it many times). It is not specific to left or right and does not appear to go away based on different tubes or by swapping input/output tubes from left to right or a rectifier tube swap. It also does not increase in volume as the volume dial is increased. The noise is NOT present at all until an input to the Aegis is turned on. (Regardless of input source) What's also strange is that it seems to increase in volume the longer Aegis is left on, but again does not become so loud that it overpowers the music itself in any way. I would also say (and this could be just one ear being more sensitive than the other) that it seems "slightly" louder in the right channel vs the left.

Here is what I'm using in my chain. Node 2 -> Schiit BiFrost 2 -> Aegis -> Atrium Open

Things I've tried so far:

• Moving Node 2 away from Aegis
• Putting all equipment plugs on single surge protector plugged into one outlet
• Plugging Aegis into outlet by itself separate from other items
• Using all three items on a separate circuit in my house
• Removing plugged in items like computers/basement fridge from the same circuit Aegis was using
• Different power cords for the Bifrost and Aegis
• Plugging all three into a Belkin power conditioner
• Plugging Node and Bifrost into Belkin with Aegis into the outlet directly
• Different tube combinations
• Replacing COAX out from Node to Bifrost with optical from Node to Bifrost
• Different sources for input including Node directly into Aegis, Bifrost into Aegis or old DVD player into Aegis
• Different RCA cables
• Making sure my phone is a good distance from Aegis.

I feel like my last remaining option is to take the Aegis and my input gear to another location (other than my house) and try it on their power to see if perhaps it just may be an issue with the power at my home unless you all can think of something else. Or maybe you can just tell me this noise is inherent in tube amps and I'm overanalyzing it. For reference (as I think @mchuckp did a really nice job on the construction of the Aegis), maybe he can post an internal photo of the unit as well.

 

[mattiastomas]

Hello fellow DIY Aegis builders/owners and @L0rdGwyn. First off, I'd like to just say that I am absolutely in love with the sound qualities of my DIY Aegis (built by @mchuckp) and this post is really just a plea for help/ideas as I've got one issue with mine that I can't seem to get rid of. What problem is that? Noise. Not a hum, but what sounds like a low level electrical noise or static. This CANNOT be heard while music is playing, but can be heard between tracks (but you do have to listen for it many times). It is not specific to left or right and does not appear to go away based on different tubes or by swapping input/output tubes from left to right or a rectifier tube swap. It also does not increase in volume as the volume dial is increased. The noise is NOT present at all until an input to the Aegis is turned on. (Regardless of input source) What's also strange is that it seems to increase in volume the longer Aegis is left on, but again does not become so loud that it overpowers the music itself in any way. I would also say (and this could be just one ear being more sensitive than the other) that it seems "slightly" louder in the right channel vs the left.

Here is what I'm using in my chain. Node 2 -> Schiit BiFrost 2 -> Aegis -> Atrium Open

Things I've tried so far:

• Moving Node 2 away from Aegis
• Putting all equipment plugs on single surge protector plugged into one outlet
• Plugging Aegis into outlet by itself separate from other items
• Using all three items on a separate circuit in my house
• Removing plugged in items like computers/basement fridge from the same circuit Aegis was using
• Different power cords for the Bifrost and Aegis
• Plugging all three into a Belkin power conditioner
• Plugging Node and Bifrost into Belkin with Aegis into the outlet directly
• Different tube combinations
• Replacing COAX out from Node to Bifrost with optical from Node to Bifrost
• Different sources for input including Node directly into Aegis, Bifrost into Aegis or old DVD player into Aegis

I feel like my last remaining option is to take the Aegis and my input gear to another location (other than my house) and try it on their power to see if perhaps it just may be an issue with the power at my home unless you all can think of something else. Or maybe you can just tell me this noise is inherent in tube amps and I'm overanalyzing it. For reference (as I think @mchuckp did a really nice job on the construction of the Aegis), maybe he can post an internal photo of the unit as well.

Sorry you’re running into that issue. Noise can be an annoying thing to track down. It’s definitely not normal, as my Aegis is dead quiet. Even with the volume turned all the way up there’s no noise.
You said that if the Aegis is on by itself that there’s no noise? If so I would check and see if the RCA connectors are plugged in all the way and not loose on both ends.
Did you also try a difference pair of RCA cables?

 

[Schuie Driver]

Sorry you’re running into that issue. Noise can be an annoying thing to track down. It’s definitely not normal, as my Aegis is dead quiet. Even with the volume turned all the way up there’s no noise.
You said that if the Aegis is on by itself that there’s no noise? If so I would check and see if the RCA connectors are plugged in all the way and not loose on both ends.
Did you also try a difference pair of RCA cables?

Yeah, to say it's been frustrating would be an understatement. That said, I love the sound from Aegis so much I just keep listening

Yep, no change in noise with different RCA cables.
Aegis is also quiet with RCA cables plugged in, but input sources turned off. Meaning the cables do not need to be disconnected in order for Aegis to be quiet on its own under power.

 

[theveterans]

Hello fellow DIY Aegis builders/owners and @L0rdGwyn. First off, I'd like to just say that I am absolutely in love with the sound qualities of my DIY Aegis (built by @mchuckp) and this post is really just a plea for help/ideas as I've got one issue with mine that I can't seem to get rid of. What problem is that? Noise. Not a hum, but what sounds like a low level electrical noise or static. This CANNOT be heard while music is playing, but can be heard between tracks (but you do have to listen for it many times). It is not specific to left or right and does not appear to go away based on different tubes or by swapping input/output tubes from left to right or a rectifier tube swap. It also does not increase in volume as the volume dial is increased. The noise is NOT present at all until an input to the Aegis is turned on. (Regardless of input source) What's also strange is that it seems to increase in volume the longer Aegis is left on, but again does not become so loud that it overpowers the music itself in any way. I would also say (and this could be just one ear being more sensitive than the other) that it seems "slightly" louder in the right channel vs the left.

Here is what I'm using in my chain. Node 2 -> Schiit BiFrost 2 -> Aegis -> Atrium Open

Things I've tried so far:

• Moving Node 2 away from Aegis
• Putting all equipment plugs on single surge protector plugged into one outlet
• Plugging Aegis into outlet by itself separate from other items
• Using all three items on a separate circuit in my house
• Removing plugged in items like computers/basement fridge from the same circuit Aegis was using
• Different power cords for the Bifrost and Aegis
• Plugging all three into a Belkin power conditioner
• Plugging Node and Bifrost into Belkin with Aegis into the outlet directly
• Different tube combinations
• Replacing COAX out from Node to Bifrost with optical from Node to Bifrost
• Different sources for input including Node directly into Aegis, Bifrost into Aegis or old DVD player into Aegis

I feel like my last remaining option is to take the Aegis and my input gear to another location (other than my house) and try it on their power to see if perhaps it just may be an issue with the power at my home unless you all can think of something else. Or maybe you can just tell me this noise is inherent in tube amps and I'm overanalyzing it. For reference (as I think @mchuckp did a really nice job on the construction of the Aegis), maybe he can post an internal photo of the unit as well.

Does not exist in mine either and this is with more sensitive Bokeh Open turned ALL THE WAY to max position and let my Saga OG preamp control the volume. Definitely something is seeping through the RCA which is probably acting like an EMI/RFI antenna to your Aegis. It’s normal for the noise to get slightly louder as the tubes keep warming up. You would need to troubleshoot where in your house is that coming from

 

[JTbbb]

Hello fellow DIY Aegis builders/owners and @L0rdGwyn. First off, I'd like to just say that I am absolutely in love with the sound qualities of my DIY Aegis (built by @mchuckp) and this post is really just a plea for help/ideas as I've got one issue with mine that I can't seem to get rid of. What problem is that? Noise. Not a hum, but what sounds like a low level electrical noise or static. This CANNOT be heard while music is playing, but can be heard between tracks (but you do have to listen for it many times). It is not specific to left or right and does not appear to go away based on different tubes or by swapping input/output tubes from left to right or a rectifier tube swap. It also does not increase in volume as the volume dial is increased. The noise is NOT present at all until an input to the Aegis is turned on. (Regardless of input source) What's also strange is that it seems to increase in volume the longer Aegis is left on, but again does not become so loud that it overpowers the music itself in any way. I would also say (and this could be just one ear being more sensitive than the other) that it seems "slightly" louder in the right channel vs the left.

Here is what I'm using in my chain. Node 2 -> Schiit BiFrost 2 -> Aegis -> Atrium Open

Things I've tried so far:

• Moving Node 2 away from Aegis
• Putting all equipment plugs on single surge protector plugged into one outlet
• Plugging Aegis into outlet by itself separate from other items
• Using all three items on a separate circuit in my house
• Removing plugged in items like computers/basement fridge from the same circuit Aegis was using
• Different power cords for the Bifrost and Aegis
• Plugging all three into a Belkin power conditioner
• Plugging Node and Bifrost into Belkin with Aegis into the outlet directly
• Different tube combinations
• Replacing COAX out from Node to Bifrost with optical from Node to Bifrost
• Different sources for input including Node directly into Aegis, Bifrost into Aegis or old DVD player into Aegis

I feel like my last remaining option is to take the Aegis and my input gear to another location (other than my house) and try it on their power to see if perhaps it just may be an issue with the power at my home unless you all can think of something else. Or maybe you can just tell me this noise is inherent in tube amps and I'm overanalyzing it. For reference (as I think @mchuckp did a really nice job on the construction of the Aegis), maybe he can post an internal photo of the unit as well.

Not mentioned in your diagnostics, and probably not a cause, but your mobile phone is well out of the way?

 

[Schuie Driver]

Not mentioned in your diagnostics, and probably not a cause, but your mobile phone is well out of the way?

Yes thank you for asking and I should update my list to include this and different RCA cables.

 

[mchuckp]

Does not exist in mine either and this is with more sensitive Bokeh Open turned ALL THE WAY to max position and let my Saga OG preamp control the volume. Definitely something is seeping through the RCA which is probably acting like an EMI/RFI antenna to your Aegis. It’s normal for the noise to get slightly louder as the tubes keep warming up. You would need to troubleshoot where in your house is that coming from

So I'm his good friend and builder of the Aegis. Couple things to add about the build itself and then all the conversations I've had with him as we've tried to track down the noise.

BUILD:

• This is my 2nd build. I was very meticulous. All testing was within spec. If there is a need for inside pix, I can supply.
• I used it at home for a number of hours over several days to test it. I did turn the volume all the way up and had zero noise (my build is the same). What I don't recall is if I had a source on it at the time. I THINK I did but not 100% sure.
• One thing I noticed during my testing was the WBT RCA inputs were a little loose on the back of the unit. I took the plate off, double checked all the connections, and tightened them. I found that since they are meant to be hand tightened, I had a hard time feeling they were snug. But they were installed corrected with the plastic ring and tightened as tight as I could.
• The item was packed quite well and shipped from OR to OH and appeared to arrive undamaged.

TROUBLESHOOTING (add'l comments to add to what he said):

• We first thought we eliminated noise when he switched his NODE>Bifrost from Coax to Toslink. But heard it again later.
• He swapped a power cable on his Bifrost and appeared to have less noise.
• He tried the Bifrost, Node, and a bluray player as a source and each provided different levels of noise (in that order from least to most)
• He moved to a different socket on the same circuit and it was quiet. So he did some dampening on the GFSI outlet he usually uses and it went quiet. But then came back later.

I don't know if there may be an issue with the Aegis and if so, what it would be. Hope was that someone on here may be able to help us at least decide if it certainly is or isn't and what to check if it could be. As noted, with some RCAs plugged into the Aegis but the DAC powered down it is dead quiet even at max volume. Once a source is added, he gets noise. But there has been times he hasn't gotten noise as noted above. So either something in the Aegis is causing the noise when it gets an incoming signal or he is picking up noise in his house.

Thanks everyone!

 

[TraugottJan]

Sounds like a killer project love that it’s all old-school tubes with no silicon.
Following for sure

 

[theveterans]

So I'm his good friend and builder of the Aegis. Couple things to add about the build itself and then all the conversations I've had with him as we've tried to track down the noise.

BUILD:

• This is my 2nd build. I was very meticulous. All testing was within spec. If there is a need for inside pix, I can supply.
• I used it at home for a number of hours over several days to test it. I did turn the volume all the way up and had zero noise (my build is the same). What I don't recall is if I had a source on it at the time. I THINK I did but not 100% sure.
• One thing I noticed during my testing was the WBT RCA inputs were a little loose on the back of the unit. I took the plate off, double checked all the connections, and tightened them. I found that since they are meant to be hand tightened, I had a hard time feeling they were snug. But they were installed corrected with the plastic ring and tightened as tight as I could.
• The item was packed quite well and shipped from OR to OH and appeared to arrive undamaged.

TROUBLESHOOTING (add'l comments to add to what he said):

• We first thought we eliminated noise when he switched his NODE>Bifrost from Coax to Toslink. But heard it again later.
• He swapped a power cable on his Bifrost and appeared to have less noise.
• He tried the Bifrost, Node, and a bluray player as a source and each provided different levels of noise (in that order from least to most)
• He moved to a different socket on the same circuit and it was quiet. So he did some dampening on the GFSI outlet he usually uses and it went quiet. But then came back later.

I don't know if there may be an issue with the Aegis and if so, what it would be. Hope was that someone on here may be able to help us at least decide if it certainly is or isn't and what to check if it could be. As noted, with some RCAs plugged into the Aegis but the DAC powered down it is dead quiet even at max volume. Once a source is added, he gets noise. But there has been times he hasn't gotten noise as noted above. So either something in the Aegis is causing the noise when it gets an incoming signal or he is picking up noise in his house.

Thanks everyone!

Thanks for the recap! I appreciate it

Just to help troubleshooting, how about trying a (offline / airplane mode) DAP straight to Aegis so literally no mains noise or anything that'll seep through Aegis? An example would be a smartphone on airplane mode, no bluetooth no radios and use a USB dongle to have 3.5mm outs then 3.5mm to RCA if you don't have a dedicated DAP

 

[mchuckp]

Thanks for the recap! I appreciate it

Just to help troubleshooting, how about trying a (offline / airplane mode) DAP straight to Aegis so literally no mains noise or anything that'll seep through Aegis?

Thanks for the suggestion. This would be a good test. He doesn't have a DAP but does have an iPad or iPhone. Not sure how to get from USB-C or Lightening directly into the Aegis.
EDIT: Maybe the apple Dongle that would go to a 3.5mm then use a 3.5mm Y cable that goes to full size RCAs??

 

[wizzman121]

Hello fellow DIY Aegis builders/owners and @L0rdGwyn. First off, I'd like to just say that I am absolutely in love with the sound qualities of my DIY Aegis (built by @mchuckp) and this post is really just a plea for help/ideas as I've got one issue with mine that I can't seem to get rid of. What problem is that? Noise. Not a hum, but what sounds like a low level electrical noise or static. This CANNOT be heard while music is playing, but can be heard between tracks (but you do have to listen for it many times). It is not specific to left or right and does not appear to go away based on different tubes or by swapping input/output tubes from left to right or a rectifier tube swap. It also does not increase in volume as the volume dial is increased. The noise is NOT present at all until an input to the Aegis is turned on. (Regardless of input source) What's also strange is that it seems to increase in volume the longer Aegis is left on, but again does not become so loud that it overpowers the music itself in any way. I would also say (and this could be just one ear being more sensitive than the other) that it seems "slightly" louder in the right channel vs the left.

Here is what I'm using in my chain. Node 2 -> Schiit BiFrost 2 -> Aegis -> Atrium Open

Things I've tried so far:

• Moving Node 2 away from Aegis
• Putting all equipment plugs on single surge protector plugged into one outlet
• Plugging Aegis into outlet by itself separate from other items
• Using all three items on a separate circuit in my house
• Removing plugged in items like computers/basement fridge from the same circuit Aegis was using
• Different power cords for the Bifrost and Aegis
• Plugging all three into a Belkin power conditioner
• Plugging Node and Bifrost into Belkin with Aegis into the outlet directly
• Different tube combinations
• Replacing COAX out from Node to Bifrost with optical from Node to Bifrost
• Different sources for input including Node directly into Aegis, Bifrost into Aegis or old DVD player into Aegis
• Different RCA cables
• Making sure my phone is a good distance from Aegis.

I feel like my last remaining option is to take the Aegis and my input gear to another location (other than my house) and try it on their power to see if perhaps it just may be an issue with the power at my home unless you all can think of something else. Or maybe you can just tell me this noise is inherent in tube amps and I'm overanalyzing it. For reference (as I think @mchuckp did a really nice job on the construction of the Aegis), maybe he can post an internal photo of the unit as well.

Well given that you only hear the noise when an input is plugged in and powered on that narrows things down and likely rules out an issue with the Aegis. I dealt with some noticeable low level hum with my DIY Aegis as well. I narrowed down the background noises two two different sources. The first was I was hearing PC noise which was quite annoying. It was more of an inconsistent scratching sound that seemed to correlate to spinning hard drive and network activity. I was able to totally eliminate this with a cheap Topping device that I discussed in this post.

The hum sound I had turned out to come primarily from my Hypsos power supply that I use with my Wandla DAC. I only hear it through the Aegis. I hear nothing out of any of my other amps. I was able to significantly reduce the hum by plugging the Hypsos into this power strip/conditioner. It is still there but only really audible with no music playing if you are past 12 o'clock on the Aegis volume pot with more sensitive headphones.