[ChJL]

I also own this amp paired with the Caldera's although just in stock form for now. In all honesty I don't feel the need to go down the NOS rabbit hole as the sound really is stellar.

Don't think this amp gets much exposure so hopefully threads like this will bring it into focus a little more.

I should add it's built like a tank and the brass plate on the top looks high end for sure!

thanks for picking up the invite!

 

[ChJL]

My prayers to the dark audiophile gods have been answered, another acolyte/owner emerges on this thread!

you're welcome as soon as I've seen that nice Pic on the Caldera thread I also was intreagued on getting some more impressions from yet another owner...

I'll have to look at tube rolling at some point but for now I'm very happy for sure!

I do think rolling the rectifier and input tubes will improve it at a less eye watering investment level than seeking out NOS 205Ds.

I asked @ Icon if they would supply different rectifier and input valves...
answer :
"Some NOS are good, but they are usually expensive as they are not many around, so you usually pay for rarity rather than quality, a good new manufacture valve is just as good"

didn't tell with which they send it out stock.

capacitor upgrade is 195 extra though...

 

[ardbeg1975]

you're welcome as soon as I've seen that nice Pic on the Caldera thread I also was intreagued on getting some more impressions from yet another owner...

Thank you.

I asked @ Icon if they would supply different rectifier and input valves...
answer :
"Some NOS are good, but they are usually expensive as they are not many around, so you usually pay for rarity rather than quality, a good new manufacture valve is just as good"

didn't tell with which they send it out stock.

capacitor upgrade is 195 extra though...

Like any proud parent, Icon likes their amps best “just as they are” with stock tubes. That said, having rolled through 8+ rectifiers with my Eddie Current and 3 on the Icon, non-stock tubes do subtly but audibly change the sound and largely for the better, specially with some (I agree not all) NOS tubes. The NOS 205Ds sound better than the Psvane. I wish they didn’t as the cost is painful due to both rarity and sonics.

I went for the upgraded capacitors because “why not” but I did skip the ~$100 Bluetooth module. I prefer Redbook and Hi-res sources but I’m not biased against Bluetooth (AirPod Pros still rule on a noisy train commute) but I didn’t need wireless input on my desk setup.

 

[ardbeg1975]

I will add that David Shaw at icon for whom I have nothing but respect has not heard a NOS WE205D set in his amp (I asked). That isn’t a dig as why should he have as the tubes are very rare in good condition and thus impractical for a builder. The Icon uses UX4 sockets for the power tubes to maximize compatibility and allow swaps between modern 205Ds and new and NOS 300B tubes which also use UX4. Vintage 205Ds use UV4 and require an adapter. As stated in earlier posts, the Psvanes sound great in the amp and are attainable BUT if you are chasing the sonic dragon to the ultimate doom of your sanity and wallet, the NOS do sound divine.

 

[ardbeg1975]

For this evening's random Icon HP205D musings, I will discuss the Mullard GZ34 metal base rectifier, a highly desirable 5AR4, in the Icon. Despite its well deserved reputation, I have mixed feelings about this valve. In the EC Studio B which is already very fast and dry, the metal base's characteristic crispness, energy, and fast transients push that particular amp to be too "urgent" in its delivery. I'm not a fan of very slow and syrupy DHT amps, but with the EC and metal base combination the pendulum swings too far in the opposite direction. However, and back to the subject of this thread, in the Icon the GZ34 works better as an alternative to 274Bs such as the Tak or Elrog. The Icon remains a more middle ground amp on the fast / slow (or dry / wet) continuum compared to the EC. The metal base nudges the Icon in a more energetic direction but never off balance. I think I'm going to ultimately use the Tak 274B more than the Mullard but some may well prefer the Icon's voicing with the metal base.

 

[geoffalter11]

For this evening's random Icon HP205D musings, I will discuss the Mullard GZ34 metal base rectifier, a highly desirable 5AR4, in the Icon. Despite its well deserved reputation, I have mixed feelings about this valve. In the EC Studio B which is already very fast and dry, the metal base's characteristic crispness, energy, and fast transients push that particular amp to be too "urgent" in its delivery. I'm not a fan of very slow and syrupy DHT amps, but with the EC and metal base combination the pendulum swings too far in the opposite direction. However, and back to the subject of this thread, in the Icon the GZ34 works better as an alternative to 274Bs such as the Tak or Elrog. The Icon remains a more middle ground amp on the fast / slow (or dry / wet) continuum compared to the EC. The metal base nudges the Icon in a more energetic direction but never off balance. I think I'm going to ultimately use the Tak 274B more than the Mullard but some may well prefer the Icon's voicing with the metal base.

Would you say that the Icon is an extremely flexible amp in that you are able to use many different combos to great effect? I love the Mullard/Amperex GZ-34 in my ECAF, whereas I found perfect 5R4GY's, even wartime versions to not be suitable to my tastes as it felt like there was a slight lag in the sound.

But, the 205D is such a different tube, you are figuring out things almost no one on here has heard. Not even the builder of the 205D has even seen a real pair of WE205Ds from the 20s.

 

[geoffalter11]

I will add that David Shaw at icon for whom I have nothing but respect has not heard a NOS WE205D set in his amp (I asked). That isn’t a dig as why should he have as the tubes are very rare in good condition and thus impractical for a builder. The Icon uses UX4 sockets for the power tubes to maximize compatibility and allow swaps between modern 205Ds and new and NOS 300B tubes which also use UX4. Vintage 205Ds use UV4 and require an adapter. As stated in earlier posts, the Psvanes sound great in the amp and are attainable BUT if you are chasing the sonic dragon to the ultimate doom of your sanity and wallet, the NOS do sound divine.

How could they not? You are talking about perhaps the greatest and one of the rarest of tubes Western Electric made, one they only made for about 8 yrs. The fact PSvane has decided to make the tube is wonderful, but I can only imagine how good those NOS 205Ds sound. I imagine them to be completely different from the DHT tubes everyone chases. I know that they were mostly used for old radios and an amplifier or two built around that time as they are not a tube built for wartime activities.

I think your description is incredible, just so hard to understand as it is such a rare beast.

 

[ChJL]

As stated in earlier posts, the Psvanes sound great in the amp and are attainable BUT if you are chasing the sonic dragon to the ultimate doom of your sanity and wallet, the NOS do sound divine

yeah one of the first things I looked for on ebay but just one search though and I guess they were 7k+...

chasing something which is close to being extinct

an extremely flexible amp in that you are able to use many different combos

anyways, since I´ve looked for quite some time for a potential HP tube amp I might just take it easy and start with a somewhat standard version... Psvane 205s and will also go

for the upgraded capacitors because “why not” but I did skip the ~$100 Bluetooth module

sounds the Icon provides a unique, high quality foundation to build upon and play around with for quite some time, especially if one just starts out with tubes!

so one could play it save and go for new stock (Tak, Psvane, WE, Elrog,...) variants and I´m getting a "feeling" for NOS rectifiers and input tubes over here:

https://www.head-fi.org/threads/dub...ifer-tube-rolling-thread.694525/post-10053310
https://www.head-fi.org/threads/692...cc-cca-7308-e188cc-tubes.761078/post-11464856

 

[ChJL]

So I've looked at this:
https://theaudiophileman.com/hp205d-head-amp-from-icon-audio/

because I wanted to find pictures of the tube base of each type.

That's correct, right?

rectifier is called octal base... so I need to find GZ34s, 274bs with 8 pins? do most/all have 8 pins?
same for 205Ds (I'm aware that WE NOS require an adapter) and 300Bs... do most/all have 4 pins?
6922/ECC88 variants... do most/all have 9 pins?
thanks!

@ardbeg1975
lets say you use the tallest tubes with it, probably 300Bs... how high is the Amp from top to bottom?
probably best to place it on top of a rack with nothing above, right?

 

[ardbeg1975]

Would you say that the Icon is an extremely flexible amp in that you are able to use many different combos to great effect? I love the Mullard/Amperex GZ-34 in my ECAF, whereas I found perfect 5R4GY's, even wartime versions to not be suitable to my tastes as it felt like there was a slight lag in the sound.

Yes, it is very flexible.

 

[ardbeg1975]

So I've looked at this:
https://theaudiophileman.com/hp205d-head-amp-from-icon-audio/

because I wanted to find pictures of the tube base of each type.

That's correct, right?

Yes

rectifier is called octal base... so I need to find GZ34s, 274bs with 8 pins? do most/all have 8 pins?

274Bs, GZ34, 5AR4. Octal base.

same for 205Ds (I'm aware that WE NOS require an adapter) and 300Bs... do most/all have 4 pins?

Yes, 4-pin UX4

6922/ECC88 variants... do most/all have 9 pins?
thanks!

Yes, all 6922 variants are 9-pins — 6DJ8, 6922, ECC88, E88CC, and 7308.

@ardbeg1975
lets say you use the tallest tubes with it, probably 300Bs... how high is the Amp from top to bottom?
probably best to place it on top of a rack with nothing above, right?

~10”