[A2029]

BH/BH+ can reach up to ~24V rms output from 1.2V rms input (using 6J5 driver tubes), so even standard 2V RCA input is plenty

 

[OctavianH]

So mr @A2029 when you are saying more about your upcoming amp?

 

[A2029]

So mr @A2029 when you are saying more about your upcoming amp?

Not quite ready for all the info to be released on that amp yet, but hopefully more info to come soon!

 

[raindownthunda]

Random musings to keep bumping this thread:

• 5998 glow is hard to beat, as is the sound
• 2 sounds good, but 4 sounds better
• i'm in love with the 5a/152m drivers... insane transparency. might be my new "reference" drivers?
• i swapped the bf2/64 for a yggy+ gs2/a1/unison about a month ago... this sounds like a completely new amp and it's taken me a long time to even begin to adjust to what i'm hearing. i really wans't expecting this dramatic of a difference. the yggy a1 has really opened my eyes/ears into how technically capable this amp truly is. hard to find the words to describe it. i'll just say i've had dozens of hours of back to back comparisons now with the nitsch dsha-3fn... and with most tube rolls the amount of information/microdetail/texture that can be heard with the blue halo+ is basically on par. however, there is a much greater sense of space, fluidity, 3d layering effects. this amp continues to amaze me.

 

[leftside]

Random musings to keep bumping this thread:

• 5998 glow is hard to beat, as is the sound
• 2 sounds good, but 4 sounds better

How about 6?

 

[raindownthunda]

How about 6?

OK, fine... For science, and posterity:



It sounds pretty good... Honestly I'm not sure how different it sounds from 2 or 4 as I got a new DAC two days ago and my brain is still adjusting.

According to Mischa's table in the Blue Halo+ guide, the output impedance of 6x 5998 drops down to 14-15 ohm. Not as drastic of a change compared to going from 2 to 4.

I have been hesitant to try 6x out. Although Mischa said the amp has extra-beefy components with enough power to handle safely, the extra strain on the components (from the heat I believe?) would likely reduce the lifespan for some of the components.

@leftside's peer pressure has been weighing on me for weeks, so I felt it was time to finally time to try this out. Out of curiosity (and being a little nervous) I decided to run an experiment to monitor the temps.

There is a temperature sensor inside my amp that was added to the LED controller board. It's not super accurate, but gives a rough idea (within a few degrees) of the ambient temperature inside the case. I check this pretty regularly to get a sense of if the amp is warmed up. I have a pretty good idea of what's within "normal range". BH runs at ~80-85 degrees and BH+ runs at 90-100 depending on tubes used.



There are two Noctua 120x15mm fans on the bottom of the case to provide active cooling. There's an external fan controller I have set to 60-65%. That seems to be the sweet spot between low noise and adequate cooling. One time I accidentally unplugged the fans, so I have seen the amp get dangerous hot (130+ F ambient). The case was scalding! I try to keep it under 100 F.

After turning amp on, I started capturing a temp reading every minute until it stopped increasing:

Highest reading was 94 F ambient. After an hour or so I cranked the fans to 100% and ambient temps rapidly dropped down to around 84 degrees F.

The results were pretty surprising to me as I've seen higher ambient temps from just 2x 6520 or 4x 6080. The sides of the amp (where most of the heat sinking happens) did feel quite hot, but unfortunately I don't have a temp gun to measure surface temps. Since I can't measure the amp chassis temps: I think the ambient readings are interesting, but not enough to draw any real conclusions from.

This was done out of curiosity, not to try to prove it's safer than the manual states. Listen to the warnings in the manual on reduced amp life!

With how good the amp sounds in all the other configurations, I don't think I'll be doing this again... 2x 6528 gets to the same output impedance as 6x 5998 in BH+ mode, and Mischa has said that shouldn't have any detrimental impact to component life span. Not to mention 6x 5998 are also at least 10x more expensive than than a pair of 6258's!

End experiment. Party mode engaged:

 

[LobalWarming]

OK, fine... For science, and posterity:



It sounds pretty good... Honestly I'm not sure how different it sounds from 2 or 4 as I got a new DAC two days ago and my brain is still adjusting.

According to Mischa's table in the Blue Halo+ guide, the output impedance of 6x 5998 drops down to 14-15 ohm. Not as drastic of a change compared to going from 2 to 4.


I have been hesitant to try 6x out. Although Mischa said the amp has extra-beefy components with enough power to handle safely, the extra strain on the components (from the heat I believe?) would likely reduce the lifespan for some of the components.

@leftside's peer pressure has been weighing on me for weeks, so I felt it was time to finally time to try this out. Out of curiosity (and being a little nervous) I decided to run an experiment to monitor the temps.

There is a temperature sensor inside my amp that was added to the LED controller board. It's not super accurate, but gives a rough idea (within a few degrees) of the ambient temperature inside the case. I check this pretty regularly to get a sense of if the amp is warmed up. I have a pretty good idea of what's within "normal range". BH runs at ~80-85 degrees and BH+ runs at 90-100 depending on tubes used.



There are two Noctua 120x15mm fans on the bottom of the case to provide active cooling. There's an external fan controller I have set to 60-65%. That seems to be the sweet spot between low noise and adequate cooling. One time I accidentally unplugged the fans, so I have seen the amp get dangerous hot (130+ F ambient). The case was scalding! I try to keep it under 100 F.

After turning amp on, I started capturing a temp reading every minute until it stopped increasing:





Highest reading was 94 F ambient. After an hour or so I cranked the fans to 100% and ambient temps rapidly dropped down to around 84 degrees F.

The results were pretty surprising to me as I've seen higher ambient temps from just 2x 6520 or 4x 6080. The sides of the amp (where most of the heat sinking happens) did feel quite hot, but unfortunately I don't have a temp gun to measure surface temps. Since I can't measure the amp chassis temps: I think the ambient readings are interesting, but not enough to draw any real conclusions from.

This was done out of curiosity, not to try to prove it's safer than the manual states. Listen to the warnings in the manual on reduced amp life!

With how good the amp sounds in all the other configurations, I don't think I'll be doing this again... 6528 gets to the same output impedance in BH+ mode and Mischa has said that shouldn't have any detrimental impact to component life span.

End experiment. Party mode engaged:

That's a whole lotta burning of very 'spensive heaters all at once. Thank you for the cheap thrills! Not cheap for you!

Wonder if the BH+ burn unit could take a pair of 7241s.... imagine would get output impedance below 10 ohms... on just 15A of heater current!

 

[ARCXENOS]

OK, fine... For science, and posterity:



It sounds pretty good... Honestly I'm not sure how different it sounds from 2 or 4 as I got a new DAC two days ago and my brain is still adjusting.

According to Mischa's table in the Blue Halo+ guide, the output impedance of 6x 5998 drops down to 14-15 ohm. Not as drastic of a change compared to going from 2 to 4.


I have been hesitant to try 6x out. Although Mischa said the amp has extra-beefy components with enough power to handle safely, the extra strain on the components (from the heat I believe?) would likely reduce the lifespan for some of the components.

@leftside's peer pressure has been weighing on me for weeks, so I felt it was time to finally time to try this out. Out of curiosity (and being a little nervous) I decided to run an experiment to monitor the temps.

There is a temperature sensor inside my amp that was added to the LED controller board. It's not super accurate, but gives a rough idea (within a few degrees) of the ambient temperature inside the case. I check this pretty regularly to get a sense of if the amp is warmed up. I have a pretty good idea of what's within "normal range". BH runs at ~80-85 degrees and BH+ runs at 90-100 depending on tubes used.



There are two Noctua 120x15mm fans on the bottom of the case to provide active cooling. There's an external fan controller I have set to 60-65%. That seems to be the sweet spot between low noise and adequate cooling. One time I accidentally unplugged the fans, so I have seen the amp get dangerous hot (130+ F ambient). The case was scalding! I try to keep it under 100 F.

After turning amp on, I started capturing a temp reading every minute until it stopped increasing:





Highest reading was 94 F ambient. After an hour or so I cranked the fans to 100% and ambient temps rapidly dropped down to around 84 degrees F.

The results were pretty surprising to me as I've seen higher ambient temps from just 2x 6520 or 4x 6080. The sides of the amp (where most of the heat sinking happens) did feel quite hot, but unfortunately I don't have a temp gun to measure surface temps. Since I can't measure the amp chassis temps: I think the ambient readings are interesting, but not enough to draw any real conclusions from.

This was done out of curiosity, not to try to prove it's safer than the manual states. Listen to the warnings in the manual on reduced amp life!

With how good the amp sounds in all the other configurations, I don't think I'll be doing this again... 2x 6528 gets to the same output impedance as 6x 5998 in BH+ mode, and Mischa has said that shouldn't have any detrimental impact to component life span.

End experiment. Party mode engaged:

6 is dangerous, you should throw 2 in my dangerous tube bin!

 

[A2029]

OK, fine... For science, and posterity:



It sounds pretty good... Honestly I'm not sure how different it sounds from 2 or 4 as I got a new DAC two days ago and my brain is still adjusting.

According to Mischa's table in the Blue Halo+ guide, the output impedance of 6x 5998 drops down to 14-15 ohm. Not as drastic of a change compared to going from 2 to 4.


I have been hesitant to try 6x out. Although Mischa said the amp has extra-beefy components with enough power to handle safely, the extra strain on the components (from the heat I believe?) would likely reduce the lifespan for some of the components.

@leftside's peer pressure has been weighing on me for weeks, so I felt it was time to finally time to try this out. Out of curiosity (and being a little nervous) I decided to run an experiment to monitor the temps.

There is a temperature sensor inside my amp that was added to the LED controller board. It's not super accurate, but gives a rough idea (within a few degrees) of the ambient temperature inside the case. I check this pretty regularly to get a sense of if the amp is warmed up. I have a pretty good idea of what's within "normal range". BH runs at ~80-85 degrees and BH+ runs at 90-100 depending on tubes used.



There are two Noctua 120x15mm fans on the bottom of the case to provide active cooling. There's an external fan controller I have set to 60-65%. That seems to be the sweet spot between low noise and adequate cooling. One time I accidentally unplugged the fans, so I have seen the amp get dangerous hot (130+ F ambient). The case was scalding! I try to keep it under 100 F.

After turning amp on, I started capturing a temp reading every minute until it stopped increasing:





Highest reading was 94 F ambient. After an hour or so I cranked the fans to 100% and ambient temps rapidly dropped down to around 84 degrees F.

The results were pretty surprising to me as I've seen higher ambient temps from just 2x 6520 or 4x 6080. The sides of the amp (where most of the heat sinking happens) did feel quite hot, but unfortunately I don't have a temp gun to measure surface temps. Since I can't measure the amp chassis temps: I think the ambient readings are interesting, but not enough to draw any real conclusions from.

This was done out of curiosity, not to try to prove it's safer than the manual states. Listen to the warnings in the manual on reduced amp life!

With how good the amp sounds in all the other configurations, I don't think I'll be doing this again... 2x 6528 gets to the same output impedance as 6x 5998 in BH+ mode, and Mischa has said that shouldn't have any detrimental impact to component life span. Not to mention 6x 5998 are also at least 10x more expensive than than a pair of 6258's!

End experiment. Party mode engaged:

Main reduction in amp lifespan running 6x of the 6080/6AS7/5998 is from the heavy current running through the electrolytic capacitors in the heater supplies. High current causes the electrolyte within the caps to heat up and dry out over time. Even with the long-life capacitor upgrade those caps see so much current when running 6x 6080/6AS7/5998 that their internal temperature would be quite a lot higher than the ambient temperature and the stress on them is pretty significant. Okay to try out for short periods once in a blue moon but definitely will reduce the lifespan of the amp if run for prolonged periods, so I generally suggest just sticking with 4x as max

 

[raindownthunda]

Main reduction in amp lifespan running 6x of the 6080/6AS7/5998 is from the heavy current running through the electrolytic capacitors in the heater supplies. High current causes the electrolyte within the caps to heat up and dry out over time. Even with the long-life capacitor upgrade those caps see so much current when running 6x 6080/6AS7/5998 that their internal temperature would be quite a lot higher than the ambient temperature and the stress on them is pretty significant. Okay to try out for short periods once in a blue moon but definitely will reduce the lifespan of the amp if run for prolonged periods, so I generally suggest just sticking with 4x as max

Thanks for the explanation @A2029! Helpful to know that the ambient temps are pretty much irrelevant. I definitely didn't feel like there was any real material benefit to running 6x from a sonic perspective. Not worth it!

 

[Xcalibur255]

My own amp gets hot enough that it triggers the hot-stove touch reflex if I put my hand on the top plate after it's been on a while, I can only imagine how much heat your PSU would be generating in that config. The fans are definitely a nice addition. I actually think more tube amps ought to have something like this. A single Noctua A14 throttled way down to 400 RPM with a resistor would be silent at a distance of more than 12 inches or so and even that modest amount of airflow would probably bring temps down meaningfully.

 

[leftside]

OK, fine... For science, and posterity:



It sounds pretty good... Honestly I'm not sure how different it sounds from 2 or 4 as I got a new DAC two days ago and my brain is still adjusting.

According to Mischa's table in the Blue Halo+ guide, the output impedance of 6x 5998 drops down to 14-15 ohm. Not as drastic of a change compared to going from 2 to 4.


I have been hesitant to try 6x out. Although Mischa said the amp has extra-beefy components with enough power to handle safely, the extra strain on the components (from the heat I believe?) would likely reduce the lifespan for some of the components.

@leftside's peer pressure has been weighing on me for weeks, so I felt it was time to finally time to try this out. Out of curiosity (and being a little nervous) I decided to run an experiment to monitor the temps.

There is a temperature sensor inside my amp that was added to the LED controller board. It's not super accurate, but gives a rough idea (within a few degrees) of the ambient temperature inside the case. I check this pretty regularly to get a sense of if the amp is warmed up. I have a pretty good idea of what's within "normal range". BH runs at ~80-85 degrees and BH+ runs at 90-100 depending on tubes used.



There are two Noctua 120x15mm fans on the bottom of the case to provide active cooling. There's an external fan controller I have set to 60-65%. That seems to be the sweet spot between low noise and adequate cooling. One time I accidentally unplugged the fans, so I have seen the amp get dangerous hot (130+ F ambient). The case was scalding! I try to keep it under 100 F.

After turning amp on, I started capturing a temp reading every minute until it stopped increasing:





Highest reading was 94 F ambient. After an hour or so I cranked the fans to 100% and ambient temps rapidly dropped down to around 84 degrees F.

The results were pretty surprising to me as I've seen higher ambient temps from just 2x 6520 or 4x 6080. The sides of the amp (where most of the heat sinking happens) did feel quite hot, but unfortunately I don't have a temp gun to measure surface temps. Since I can't measure the amp chassis temps: I think the ambient readings are interesting, but not enough to draw any real conclusions from.

This was done out of curiosity, not to try to prove it's safer than the manual states. Listen to the warnings in the manual on reduced amp life!

With how good the amp sounds in all the other configurations, I don't think I'll be doing this again... 2x 6528 gets to the same output impedance as 6x 5998 in BH+ mode, and Mischa has said that shouldn't have any detrimental impact to component life span. Not to mention 6x 5998 are also at least 10x more expensive than than a pair of 6258's!

End experiment. Party mode engaged:

Very nice!

 

[leftside]

Main reduction in amp lifespan running 6x of the 6080/6AS7/5998 is from the heavy current running through the electrolytic capacitors in the heater supplies. High current causes the electrolyte within the caps to heat up and dry out over time. Even with the long-life capacitor upgrade those caps see so much current when running 6x 6080/6AS7/5998 that their internal temperature would be quite a lot higher than the ambient temperature and the stress on them is pretty significant. Okay to try out for short periods once in a blue moon but definitely will reduce the lifespan of the amp if run for prolonged periods, so I generally suggest just sticking with 4x as max

My "ridiculous" "V6 Thunder" is fine with 6 5998's tho right? Well, it's been running that config for almost 4 years, so I presume so. Sometimes I do throw in 6 6080 or 6 6AS7G for fun as well.

 

[A2029]

My "ridiculous" "V6 Thunder" is fine with 6 5998's tho right? Well, it's been running that config for almost 4 years, so I presume so. Sometimes I do throw in 6 6080 or 6 6AS7G for fun as well.

Yup, no problem for your mega beast V6 amp.

 

[raindownthunda]

Listening to some humble 6922 equivalents on the Blue Halo+ tonight and having fun with iPhone 15PM exposure settings.

First up was the Brimar 6BQ7A + GEC 6080 (pair). Wasn't doing it for me. Didn't sound terrible, but seemed dry and lacking that tube magic. These Brimar's are NOS - maybe they need some burn in? Didn't last long enough to take a picture... I know we can do better...

Keeping the GEC 6080, I tried a pair of late 50's Melz 6N1P. Much better. Vocals sound lovely - noticable increase in creaminess (without being overly lush). Sweeter and more rounded edges. Detail and spatial information is there, but it's just a bit smooth and relaxed. Explosive sub-bass with electronic tracks that seems to extend into the depths of the Mariana trench. This is a fun listen, but I want to really want to see what the Yggy+ MIB can do with tubes, and I know there is more microdetail and spatial information to be uncovered.

Sticking with the Melz 6N1P, I swapped the power tubes to a pair of Tung-Sol 7802. Despite looking very similar to the Tung-Sol 6080 (there are subtle differences), these have nearly 3x the transconductance of the 6080 (20,000 vs 7,000 µmhos). If my math is correct (@A2029 keep me honest) a pair of these run the amp at about ~28-30 ohm output impedance.

Immediately noticable is more grip, speed, and slightly higher fidelity sound. Space around notes feels larger. Layering more holographic. More microdetail. Texture in instruments more nuanced and tactile. Vocals haunting. Despite the increased grip and sharpness, there is still a lovely sense of finesse and sweetness.

Sticking with the 7802, I swapped in the Foton 6N6P. This is simply awesome. The grip, clarity, layering, microdetail, texture, slam - it's all there. Defying logic, there's ALSO a greater sense of smoothness, fludity, and slight decay that's absolutely ear melting. The sound manages to stay totally coherent without falling apart from diffusion.

Listening to "Throw Me a Line" by HAEVN and "Thingamajig" by Miya Folick, two of my favorite male/female vocal tracks (respectively) are both utterly haunting.

"Pink+White" by Remi Wolf (live at Electric Lady version) sounds like instruments are coming from behind my head.

"Murmuration" by Joaquín Cornejo portrays a holographic array of delicate notes cascading down a sonic waterfall. It's hard to fathom the amount of spatial information that I'm picking up with absolute clarity. The notes are portrayed in the headstage in an intricate and chaotic pattern, extremely tiny in proportion like a single pixel on a 4K TV. I can pinpoint the exact location of each new note and the relative juxtaposition of each prior note. Observing a spewing geyser of microdetail droplets like I’m Neo in the Matrix. I've never heard anything like it.

"Resynthesis 3D" by Max Cooper blurs the lines between sobriety and a psychadelic headspace.

I'm a big fan of how the 6922 family is sounding in the BH+. It's worth noting that every single one of these tube rolls was DEAD silent. Zero hum, white noise. Totally black background with no music palying. I have't tried them in BH mode yet... and I still have a handful of other 6922 equivalents to try out, but there's no way I'm giving up this sound tonight.

Some other day I'll try these tubes with some of other other higher transcondunctance power tube rolls (6528, 6336, 6x 6bl7, etc) to see if the magic is still there.

P.S. The Yggy+ MIB synergy is ridiculously good with the Blue Halo!!