[Aleksandar R.]

Imc

I could hear a significant difference between the SAEQ HSA-1c solid state- and Felix Envy tube-amp, driving Immanis through the transformer interface.

I still could hear a significant difference with SAEQ HSA-1c direct drive, so the transformer does change something, but even passes through the amp character.

And - even the amp might react to the different impedance load.
So, there‘s no way to finally check with your own rig.

Very good points.

Regarding the amp's behavior with different load, that could be very significant part, depending on the amp.

HSA driving headphones direct or via the Interface, as I sometimes do at Shows, is a very specific case of showing what changes in amplifier behavior with extremely different load.
HSA-1a/b/c is loaded with 1 Ohm when driving headphones directly (headphones, cable and internal ballast resistor).
In that case, higher order distortion harmonics are more pronounced than in the case of plugging a 32 Ohms load provided by the Interface.
The amp itself becomes more benign in high-order distortion products and mellows down significantly.
No surprise, given that the current it needs to swing is reduced ~10 times.
The Transformer Interface isn't really "rounding" the sound, but the amp itself behaves differently with lower load. (Higher impedance is lower load)

A Power J-FET Single Ended amp like Firstwatt J2 is very sensitive to load and it sound quite different if loaded with 8 Ohms or 32 Ohms. Distortion products do not change in order (it has nothing over 5th harmonic in any case), but the quantity of distortion changes a lot. Enough so that with 32 Ohms, it sounds like a regular solid-state amp with no specific character and quite neutral, while with 8 Ohm load, it sound like a full-bodied Single Ended amp, as the level of 2nd harmonic has risen for ~15dB.

Large speaker amps that have multiple output transistors with total bias of 0.5A per bank, pretty much never leave Class-A when on 32 Ohm load and asked to deliver only 2-3 Watts. They will either not change the sound at all, or become more refined.

Amps with very tight control of distortion, like Benchmark AHB2 that feature error correction circuitry instead of a classic negative feedback loop, or "compound" amps with output section inside the feedback loop of input op-amp, don't really care.
You can plug in a resistor 2 Ohm load in series to headphones, or a 4-32 Ohms Transformer Interface, it will sound the same. It'll only clip sooner with 2 Ohm load.

Basically, Transformer Interfaces are very transparent and will easily transfer the behavior of the amp. However, there are large differences of how the amp itself will behave when loaded outside its expected load.

In general, large speaker amps will sound pretty much the same or smoother at 32 Ohms, headphone amps should be loaded with 32 Ohms and SET's should be loaded with 8 Ohms. That way you will make sure that the amp hasn't lost it's character and the Interface will just reflect that to headphones.

 

[HiFiDJ]

Anybody own a yammy (yh5000) to compare? Would be interesting to hear how it holds up...

 

[MokhaMark]

So, I was going to just ask this on Saturday at CanJam, but think maybe it's better to ask it here for the benefit of all (sorry if this is already well trodden territory, I'm new to this ribbon thing!): to what extent does the interface allow the character of the amp to come through? If I have, for example, a DNA Stellaris that I particularly like the sound of, to what extent can I expect the character of that sound to be transmitted through the energizer/interface? Or is the amp merely a power source, i.e. solid state vs tubes will make little or no difference because the energizer converts all of that energy either way into something the ribbon can ingest?

I would agree with others, the interface boxes just let the amplifier do the talking, but the behavior is different based on the type of circuit. The very first thing you will notice, however, is gain and drive, especially bass response. I've tried a pretty good number of speaker and headphone amps with the both the old speaker interface, and the the new TI1b. The basic data (watts per channel) do not tell the whole story. You will notice important differences in gain that make or break the combination, and it is especially noticeable in bass quantity and impact, and treble stridency. As I write this, I believe Alex has given a more technical explanation, LOL. Here you have my luddite's opinion.

You mentioned the DNA Stellaris. I do not know if that has a lot more power than the Stratus or not, but I spent some time using my Stratus using the TRS output (low impedance setting) into the TI1b (16 ohm input) listening to the SR1a. Both of the new multi ribbon headphones are supposed to be more sensitive than the SR1a, so they may very well work better or really nicely like this. But it just was not enough juice for the SR1a if deep bass was expected. Now, with solo piano, it was magical. But for most other genre, even the simple Jotunheim R performed more to expectations. But the timbre was spectacular.

Personally I am hoping the new ones are more efficient and work even better with our favorite 2A3 amplifiers!

 

[Aleksandar R.]

...

Personally I am hoping the new ones are more efficient and work even better with our favorite 2A3 amplifiers!

Will try Yamamoto A-011 soon in Israel at Byrdio - Analog Audio!

I expect it to be a wonderful match...

 

[MokhaMark]

Will try Yamamoto A-011 soon in Israel at Byrdio - Analog Audio!

I expect it to be a wonderful match...

oh cool, I love the look of that. Safe travels.

 

[nfandi]

Very good points.

Regarding the amp's behavior with different load, that could be very significant part, depending on the amp.

HSA driving headphones direct or via the Interface, as I sometimes do at Shows, is a very specific case of showing what changes in amplifier behavior with extremely different load.
HSA-1a/b/c is loaded with 1 Ohm when driving headphones directly (headphones, cable and internal ballast resistor).
In that case, higher order distortion harmonics are more pronounced than in the case of plugging a 32 Ohms load provided by the Interface.
The amp itself becomes more benign in high-order distortion products and mellows down significantly.
No surprise, given that the current it needs to swing is reduced ~10 times.
The Transformer Interface isn't really "rounding" the sound, but the amp itself behaves differently with lower load. (Higher impedance is lower load)

A Power J-FET Single Ended amp like Firstwatt J2 is very sensitive to load and it sound quite different if loaded with 8 Ohms or 32 Ohms. Distortion products do not change in order (it has nothing over 5th harmonic in any case), but the quantity of distortion changes a lot. Enough so that with 32 Ohms, it sounds like a regular solid-state amp with no specific character and quite neutral, while with 8 Ohm load, it sound like a full-bodied Single Ended amp, as the level of 2nd harmonic has risen for ~15dB.

Large speaker amps that have multiple output transistors with total bias of 0.5A per bank, pretty much never leave Class-A when on 32 Ohm load and asked to deliver only 2-3 Watts. They will either not change the sound at all, or become more refined.

Amps with very tight control of distortion, like Benchmark AHB2 that feature error correction circuitry instead of a classic negative feedback loop, or "compound" amps with output section inside the feedback loop of input op-amp, don't really care.
You can plug in a resistor 2 Ohm load in series to headphones, or a 4-32 Ohms Transformer Interface, it will sound the same. It'll only clip sooner with 2 Ohm load.

Basically, Transformer Interfaces are very transparent and will easily transfer the behavior of the amp. However, there are large differences of how the amp itself will behave when loaded outside its expected load.

In general, large speaker amps will sound pretty much the same or smoother at 32 Ohms, headphone amps should be loaded with 32 Ohms and SET's should be loaded with 8 Ohms. That way you will make sure that the amp hasn't lost it's character and the Interface will just reflect that to headphones.

Alex, last Saturday we used the Feliks Audio Envy with the 32Ohm interface and you stated that headphone amps should be used with the 32Ohm interface. But, the Feliks Envy is a SET amp and should therefore be used with the 8Ohm interface. I’m confused . Please can you put me out of my misery?

 

[byrdparis]

im not Alex, but i think to your question,
1 - he was trying to show how to work with the 32ohm interface as he didnt had the 8 prepared... (just an assumption)
2 - if you connect to the ENVY 32ohm interface the power will divided by 4, so you will get 2W a side that is more than enough for the IMMANIS and you will keep your THD below 1%.
just a thought. i bet you can use them both (8 and 32) interfaces with the Envy.

best!

 

[KaiSc]

Looking at Feliks Audio Envy‘s specs: https://feliksaudio.pl/product/envy/ it‘s not even specified for 8 Ohm load.
Max. power is 5W @ 16 Ohm 1% THD, 8 W @ 16 Ohm 5% THD.

A transformer always has a lower than nominal impedance in the sub frequency range.
Therefore Envy might feel better when loaded with 32 Ohm nominal.

 

[nfandi]

im not Alex, but i think to your question,
1 - he was trying to show how to work with the 32ohm interface as he didnt had the 8 prepared... (just an assumption)
2 - if you connect to the ENVY 32ohm interface the power will divided by 4, so you will get 2W a side that is more than enough for the IMMANIS and you will keep your THD below 1%.
just a thought. i bet you can use them both (8 and 32) interfaces with the Envy.

best!

1) This is correct. When buying Immanis as a full set it comes with the 32Ohm interface as standard. The 8Ohm and 16Ohm interfaces can be ordered also but this must be specified at the time of placing the order. We only had the 320hm interface last weekend in Heidelberg.

2) I have an Envy at home for a few days to try but alas not with Immanis, not yet. I have the old interface the TI-1b here also so I can listen with my SR-1b and CA-1a, and also directly with my Caldera.

I have an opportunity to buy the Envy and just wanted clarification, if I decide to keep it, which of the three interface options will partner best with Envy and Immanis. Thank you for your input.

 

[nfandi]

Looking at Feliks Audio Envy‘s specs: https://feliksaudio.pl/product/envy/ it‘s not even specified for 8 Ohm load.
Max. power is 5W @ 16 Ohm 1% THD, 8 W @ 16 Ohm 5% THD.

A transformer always has a lower than nominal impedance in the sub frequency range.
Therefore Envy might feel better when loaded with 32 Ohm nominal.

Thank you Kai. I started with the 16Ohm connection on the TI-1b last night but will switch to the 32Ohm for tonight‘s listening. There’s also the low, mid, high impedance settings on the Envy to take into account.

 

[byrdparis]

Thank you Kai. I started with the 16Ohm connection on the TI-1b last night but will switch to the 32Ohm for tonight‘s listening. There’s also the low, mid, high impedance settings on the Envy to take into account.

i think they are now called Gain and not impedance as they were confusing to sum
i think when you go with the 32ohm, you will need to get it to the HI (32 will drop the power by 75%).

 

[LucyWu]

I have an opportunity to buy the Envy and just wanted clarification, if I decide to keep it, which of the three interface options will partner best with Envy and Immanis. Thank you for your input.

Hi - I was wondering how you find the bass of the SR1a with the Envy? My hankering after a nice tube amp is strong but I haven't yet had a chance to listen to the Envy and I don't want to go out of my way to audition something with a flabby bottom. I know the Kallyste Amethyste offers a taught, potent low end, but it's double the price of the Envy. You seem to be enjoying it, so thought I'd seek your view.

 

[nfandi]

i think they are now called Gain and not impedance as they were confusing to sum
i think when you go with the 32ohm, you will need to get it to the HI (32 will drop the power by 75%).

Yes you’re right, my unintentional mistake. It is indeed a gain setting.

 

[nfandi]

Hi - I was wondering how you find the bass of the SR1a with the Envy? My hankering after a nice tube amp is strong but I haven't yet had a chance to listen to the Envy and I don't want to go out of my way to audition something with a flabby bottom. I know the Kallyste Amethyste offers a taught, potent low end, but it's double the price of the Envy. You seem to be enjoying it, so thought I'd seek your view.

I only set up the Envy yesterday evening and so haven’t really sorted out what I’m doing. However, the Caldera is back on the shelf and today’s listening will be entirely with my Raals using the TI-1b interface. I doubt very much that any amplifier can give the SR a flabby bottom but I will listen later and post my thoughts here. I think the Envy has reviewed well in terms of its bass but no review can be a substitute for a live audition. Start saving now if you like the Raal ‘sound’ but would like it to be fuller and with deeper bass. Immanis has landed.

 

[Aleksandar R.]

Alex, last Saturday we used the Feliks Audio Envy with the 32Ohm interface and you stated that headphone amps should be used with the 32Ohm interface. But, the Feliks Envy is a SET amp and should therefore be used with the 8Ohm interface. I’m confused . Please can you put me out of my misery?

Sorry, I was unclear.
When I said SET, I meant a speaker amp, and I lumped the Envy in "headphone amps".