[Pharmaboy]

Beautiful looking, beautiful sounding! By the experience conferred upon me - via ownership of Atrium & HP Signature - you are pronounced amp & headphone!!

What a bizarre thing to say (yet I'm snickering).

 

[jonathan c]

Prompted by the stunning visual match between @YtseJamer's Atrium & HP8

 

[YtseJamer]

Prompted by the stunning visual match between @YtseJamer's Atrium & HP8

Hey Jonathan, just wanted to quickly thank you for putting this amp on my radar through your posts. Your recommendation was spot-on, and I genuinely appreciate it. It's surprising to me that this amp isn't more popular, especially considering how well it compares to some of the best tube amps from Cayin, Woo, or Feliks.

 

[G8torbyte]

Welcome home! I missed my HP-8 while it was away a few days in Canada for a tune-up. Audioarcan did excellent work fixing the hum issue I mentioned earlier in the thread and they upgraded it with the Mundorf capacitors at my request. Great customer service with Warren, much appreciated. Enjoying it now with some NOS tubes: JAN-Philips 5751 and Zenith (GE)s.

 

[infinity3914]

I think I'm at my wit's end with the RF interference and I'm losing it...

I just moved to a new apartment in the same building - higher and not facing the street, which is much more peaceful (no more random people yanking on your backdoor at 5 am ). However, the past 2 days have been irritating as my HP8 is picking up random radio signals from somewhere. The static is back again, but this time it gets worse as I turn up the output impedance. I tried a group loop isolator, but that barely helped. I tried plugging the HP8 and DAC in the same outlet, but that didn't help. Tube swapping, different power cables, and aluminum foil didn't help either. Oddly, what helps the most is using my Heresy as a preamp and placing it on top of the power transformer (??)

As I was seething and malding, I looked outside and well duh, no wonder why it keeps picking up RF. I don't think removing the cell tower is an option, so do you guys have any suggestions?

 

[JonT]

I think I'm at my wit's end with the RF interference and I'm losing it...

I just moved to a new apartment in the same building - higher and not facing the street, which is much more peaceful (no more random people yanking on your backdoor at 5 am ). However, the past 2 days have been irritating as my HP8 is picking up random radio signals from somewhere. The static is back again, but this time it gets worse as I turn up the output impedance. I tried a group loop isolator, but that barely helped. I tried plugging the HP8 and DAC in the same outlet, but that didn't help. Tube swapping, different power cables, and aluminum foil didn't help either. Oddly, what helps the most is using my Heresy as a preamp and placing it on top of the power transformer (??)

As I was seething and malding, I looked outside and well duh, no wonder why it keeps picking up RF. I don't think removing the cell tower is an option, so do you guys have any suggestions?

I sympathise - in 2020 I moved from south west to south east London, right in the shadow of several famous radio masts in Crystal Palace.

I am sure you have tried this, but the permanent fix for me was moving to properly shielded interconnects (as in, old fashioned electrical theory inspired interconnects). In my case, these: https://www.hifisystemcomponents.com/interconnects-cables/cusat50-interconnect.html

Problem was solved.

 

[G8torbyte]

I think I'm at my wit's end with the RF interference and I'm losing it...

I just moved to a new apartment in the same building - higher and not facing the street, which is much more peaceful (no more random people yanking on your backdoor at 5 am ). However, the past 2 days have been irritating as my HP8 is picking up random radio signals from somewhere. The static is back again, but this time it gets worse as I turn up the output impedance. I tried a group loop isolator, but that barely helped. I tried plugging the HP8 and DAC in the same outlet, but that didn't help. Tube swapping, different power cables, and aluminum foil didn't help either. Oddly, what helps the most is using my Heresy as a preamp and placing it on top of the power transformer (??)

As I was seething and malding, I looked outside and well duh, no wonder why it keeps picking up RF. I don't think removing the cell tower is an option, so do you guys have any suggestions?

Yeah, I've noticed as well that the HP-8 will pick up noise from a mobile phone or wireless devices if in proximity.
Maybe a Faraday Cage could shield it? https://backyardbrains.com/experiments/faraday

 

[JerseyD]

I think I'm at my wit's end with the RF interference and I'm losing it...

I just moved to a new apartment in the same building - higher and not facing the street, which is much more peaceful (no more random people yanking on your backdoor at 5 am ). However, the past 2 days have been irritating as my HP8 is picking up random radio signals from somewhere. The static is back again, but this time it gets worse as I turn up the output impedance. I tried a group loop isolator, but that barely helped. I tried plugging the HP8 and DAC in the same outlet, but that didn't help. Tube swapping, different power cables, and aluminum foil didn't help either. Oddly, what helps the most is using my Heresy as a preamp and placing it on top of the power transformer (??)

As I was seething and malding, I looked outside and well duh, no wonder why it keeps picking up RF. I don't think removing the cell tower is an option, so do you guys have any suggestions?

That Faraday cage idea may actually work, but first, try shielded power cables and interconnects for your whole system (not necessarily expensive); possibly a power filter (I actually have one of these on order in hopes of lowering the noise floor: Pine Tree Audio Iso-Power 15A Power Filter). Keep us posted!

 

[Jay Smith]

I think I'm at my wit's end with the RF interference and I'm losing it...

I just moved to a new apartment in the same building - higher and not facing the street, which is much more peaceful (no more random people yanking on your backdoor at 5 am ). However, the past 2 days have been irritating as my HP8 is picking up random radio signals from somewhere. The static is back again, but this time it gets worse as I turn up the output impedance. I tried a group loop isolator, but that barely helped. I tried plugging the HP8 and DAC in the same outlet, but that didn't help. Tube swapping, different power cables, and aluminum foil didn't help either. Oddly, what helps the most is using my Heresy as a preamp and placing it on top of the power transformer (??)

As I was seething and malding, I looked outside and well duh, no wonder why it keeps picking up RF. I don't think removing the cell tower is an option, so do you guys have any suggestions?

I had static noise years ago found out that it caused by a pair of TP link powerline wi-fi extenders. After removing those extenders problem fixed. Hope it helps.

 

[shabta]

I had static noise years ago found out that it caused by a pair of TP link powerline wi-fi extenders. After removing those extenders problem fixed. Hope it helps.

I had the same experience as well.

 

[Pharmaboy]

I think I'm at my wit's end with the RF interference and I'm losing it...

I just moved to a new apartment in the same building - higher and not facing the street, which is much more peaceful (no more random people yanking on your backdoor at 5 am ). However, the past 2 days have been irritating as my HP8 is picking up random radio signals from somewhere. The static is back again, but this time it gets worse as I turn up the output impedance. I tried a group loop isolator, but that barely helped. I tried plugging the HP8 and DAC in the same outlet, but that didn't help. Tube swapping, different power cables, and aluminum foil didn't help either. Oddly, what helps the most is using my Heresy as a preamp and placing it on top of the power transformer (??)

As I was seething and malding, I looked outside and well duh, no wonder why it keeps picking up RF. I don't think removing the cell tower is an option, so do you guys have any suggestions?

Just stuff you're probably already aware of:

1 - Is your cellphone anywhere near the HP8?
2 - Is your router (any Wi-Fi broadcasting component) near the HP8?

 

[infinity3914]

Hi all, appreciate all of your advice and suggestions! I've tried some of these ideas but couldn't get rid of the RFI

I sympathise - in 2020 I moved from south west to south east London, right in the shadow of several famous radio masts in Crystal Palace.

I am sure you have tried this, but the permanent fix for me was moving to properly shielded interconnects (as in, old fashioned electrical theory inspired interconnects). In my case, these: https://www.hifisystemcomponents.com/interconnects-cables/cusat50-interconnect.html

Problem was solved.

I'd have bought these if they were in the States. Does anyone know any alternative source? I'm just using some XLR to RCA cables from Cable Matter at the moment.

I had static noise years ago found out that it caused by a pair of TP link powerline wi-fi extenders. After removing those extenders problem fixed. Hope it helps.

I had the same experience as well.

I remember reading this far up the thread the other night. Unfortunately (or fortunately) I don't have any Wi-fi extenders, and I'm running ethernet to my PC...

Yeah, I've noticed as well that the HP-8 will pick up noise from a mobile phone or wireless devices if in proximity.
Maybe a Faraday Cage could shield it? https://backyardbrains.com/experiments/faraday

I bought some military-grade, Faraday fabric off Amazon and it unfortunately didn't work. I taped it up to cover my window, tried covering the back side of the amp, tried covering the tubes, and tried covering the entire amp, but the RF interference still leaked through. Return

That Faraday cage idea may actually work, but first, try shielded power cables and interconnects for your whole system (not necessarily expensive); possibly a power filter (I actually have one of these on order in hopes of lowering the noise floor: Pine Tree Audio Iso-Power 15A Power Filter). Keep us posted!

This was my initial thought, that my power is not clean. I tried two different surge protectors, and plugged my amp into a Sinewave UPS running pink noise overnight, but neither got rid of the RFI At this point, I'm grabbing one of those power filters and hoping for the best.

Just stuff you're probably already aware of:

1 - Is your cellphone anywhere near the HP8?
2 - Is your router (any Wi-Fi broadcasting component) near the HP8?

Hey Peter, thanks for asking. I usually have my phone at my desk, but for testing last night I moved it away. It helped a little bit, but I did notice that hovering and swinging my phone around the amp "warped" the RFI sound, as in, I'm bending the RFI. This morning it's not anywhere near my amp and the RFI is still here :/ I also don't have any Wi-Fi broadcasting component near the amp as my router is in another room, two walls away.

Things I've also tried the past two days and their effectiveness:

• Moving the HP8 away from the window: didn't help.
• Putting all audio components on one surge protector: didn't help.
• Ferrite chokes/beads: LOTS OF THEM. Where there is a cable, there are two chokes. What helped most was the choke on the headphone cable, coming out of the amp. This got rid of maybe 60% of the RFI.
• IFI SilentPower, GND Defender: didn't help, at all. It also didn't help the last time I got this problem, so I wouldn't recommend this stupid expensive block to anyone.
• Tylenol: helps a lot, but didn't get rid of the RFI.
• RCA Ground loop isolator: also didn't help, actually made it worse. This helped last time though.
• Different XLR to RCA cables: didn't help. But since these are longer, I could wrap them around the power transformer into a coil. This actually helped a ton and got the RFI down significantly to just background noise. Now when I listen to orchestra or film scores with lots of quiet passages, it sounds like the ADHD voices in my head. For busier genres, it's ignorable.
• This is very strange, but using my Heresy as a preamp and placing it on top of the power transformer noticeably suppressed the RFI. I don't understand the physics of this, but it was an odd phenomenon. Also having all of the components touching each other worked amazingly. Pictured is my ridiculous-looking, Frankensteined setup that reduces the RFI noise to a barely audible, whisper level.

Some observations:

• Gripping and holding the RCA cables noticeably reduced the RFI loudness, so could this be a grounding issue? But then the IFI SilentPower block and running my amp through a UPS didn't do much, so I'm not sure.
• The noise gets louder as I turn up the impedance switch. I can only listen to my Atrium and HD800s at the medium impedance setting. High impedance sounds like TV static.
  • Though interestingly, this is coming from only the left channel, and it's independent of tube types. I might have to bring the amp to a local tube amp repairman and have him look at it.

What's next for me:

• Grab a good quality power conditioner/filter from Amazon per @JerseyD's recommendation. I'm thinking this Furman one for its small footprint. Does anyone have experience with a power conditioner/filter that isn't massive?
• Bring the HP8 out to the shop when I pick up my QSA. At this point, I'm hoping that there's an electrical component issue that's fixable. I mean, this is still better than dealing with invisible radio waves.

Thanks everyone for chiming in! I'll keep y'all posted if I manage to not lose it.

Edit: If nothing helps, I might have to give up, sell my HP8, and go back to solid-state... I'm open to recommendations for a comparable solid-state amp (used), at $1000 - $1500. I've been looking at the Schiit Mjolnir 3, Violetric V281, Cayin IHA-6/IHA-8, Ferrum Oor, IFI Pro ICAN, and HeadAmp GS-X MK-2.

 

[JerseyD]

Hi all, appreciate all of your advice and suggestions! I've tried some of these ideas but couldn't get rid of the RFI

I'd have bought these if they were in the States. Does anyone know any alternative source? I'm just using some XLR to RCA cables from Cable Matter at the moment.

A quick look at the Blue Jeans Cable site (a trusted cable seller) suggests the Belden 1694A:
"Belden 1694A is also an excellent choice for analog audio; its foil/braid shield, though slightly less effective at excluding low-frequency EMI than 1505F's double braid shield, provides better RFI rejection, so 1694A may provide better shielding performance if you are beset with RFI issues. 1694A is an RG-6 type solid-core cable, and so is somewhat thicker and stiffer than 1505F."

I would suggest a conversation with them about all your cabling and issues. They will customize your connectors as needed.

 

[lauthoerer]

I totally feel you @infinity3914 - for whatever reason my interconnects this week started to give a hum to all my headphones above 30 ohms. E3 is fine, but from the Bokeh up, it just gets worse, especially on the VC

Thanks to all the helpful tips, I was able to make out the cables as the culprit, but still a ways to go to fully get rid of it.

 

[lauthoerer]

Anyway, with what I managed so far, I’ve been able to very much enjoy going through Pearl Jam’s entire catalogue, rotating all my HPs through the HP8 and got back to the HD820 for Binaural and - damn! I didn’t care about rotating anything, except the 2 Riot Act LPs that came next

There is NOTHING wrong with the bass on that can!