[g0ldl10n]

Alright let's compare apples to apples. I've used EL81 in Ultimate many times but never as a side by side comparison with Oblivion. So here we go.

Ultimate - 6S3P, Siemens 6CJ6 (EL81), Tesla EZ81. Single Ended amp.
Oblivion - Marconi 6AV6, Siemens CV2721 (EL81). Balanced amp.

Now Ultimate soundstage opens up with the 6S3P and EL81 but Oblivion still sound more wide spread, deeper, higher. Tone wise they are more alike now and we're splitting hairs here but I have a slight preference with Oblivion on EL81 tubes. Both are gorgeous sounding.

Remember that Tomas chose EL81 specifically for Oblivion because he said the tube measures very linear. Likewise he chose EL36 for Citadel.

Both are incredibly good looking too. I've decided to lose the socket savers in Ultimate for this photoshoot.

Dimensions are almost the same.
Ultimate - 43 mm x 31 mm x 9 mm
Oblivion - 45 mm x 29 mm x 9 mm

Whoa!! Those are some tiny amps.

Ultimate coming in at 43 millimeters, that has got to be some sort of record!!

 

[UntilThen]

43 cm. Just to trick you into thinking it will fit easily on your desktop or the palm of your hand.

 

[mordy]

Ask Eric what he thinks of an amp using 6528/6336 tubes with 12AV7?

 

[UntilThen]

Ask Eric what he thinks of an amp using 6528/6336 tubes with 12AV7?

I did but he wasn’t very keen on 6336. However if a client ask for it I’m sure he can accommodate it.

 

[crakers7]

@UntilThen will you be adding some more of Erics speaker amp details and types ?

 

[UntilThen]

@UntilThen will you be adding some more of Erics speaker amp details and types ?

Yeah as I go along. A lot have been described in the other thread. As I see it, there are only 2 that I am interested in. The KT170 amp (uses a lot of the pentodes and beam tetrodes) and the 300b amp.

@rollinbr Chameleon is really a KT170 amp that uses Super Silk output transformers. That's a beautiful muscular amp and at the Arizona meet, those guys love it driving Susvara !

There's also the Push Pull that has a lot more power for speakers. 6L6GC or KT150. You're looking at 25w and 50w respectively.

My previous Destiny 300b amp is really a speaker amp at 8 watts but it drives Susvara with great bass and authority. I went with Interstage transformers instead of caps. That's $300 extra. By right I shouldn't have sold off that amp but there are a lot of things I shouldn't have done in this journey.

I had already paid up for Telemachus 90% of the cost and could almost smell it but then tragedy strikes and I didn't get to see it in real life. This was the amp I was willing to give up Destiny for even though I haven't heard Telemachus.

This is Telemachus 10 beautiful watts with Monolith Magnetics output transformers. Now I can only speculate what life would be like if I had gotten it.

 

[UntilThen]

Still waiting on Silk output transformers but Matt's Super Black Ultimate with everything is taking shape. Black does look nice.

 

[UntilThen]

Finally the Silk transformers from https://www.sacthailand.com/ arrived for the KT150 amp. I may get hold of this amp for an audition on Thursday or Friday.

 

[UntilThen]

It's confirm. I will be picking up the KT170 amp on Thursday morning and will only keep it until Sunday morning. I ask Eric why it's call KT150 amp instead of KT170 amp. Eric's reply is that the customer ordered it with KT150 tubes. So it could be call whatever because it will handle KT170, KT150, 6550, EL34, 807, etc.

This amp design is different from Ultimate. This amp will use 6EM7 as drivers. Heavy duty drivers. Bigger power supply and will use 5 volt rectifier. Bias for the power tubes will be fixed, i.e. I have to manually set it. So I can set KT88 to 60mA and EL12 spez to 50mA, etc.

I will be doing the test with Susvara and HD800. Part of the purpose of my test is to see if GEC 807 ATS25 or VT60 will sound better in this KT170 amp or Ultimate. I will be doing the same with the other power tubes - 6550, EL34, EL39, EL38, etc. Ultimate is auto bias and we know that 807, EL39, EL12 spez sound great in Ultimate but will it sound better in the fixed bias KT170 amp. This will be one of the main focus of my test.

Lastly, as the KT170 amp is a speaker amp of about 11 watts, I will test it driving my speakers - both bookshelf and floorstanders. Both are Axis Technology speakers made by John Reilly, the man with the golden ears. John was in my living room btw and we were listening to Led Zeppelin 'Stairway to heaven' with the speakers made by him or his workers. His design. This was several years ago.

The Axis speakers in my lounge.

 

[crakers7]

It's confirm. I will be picking up the KT170 amp on Thursday morning and will only keep it until Sunday morning. I ask Eric why it's call KT150 amp instead of KT170 amp. Eric's reply is that the customer ordered it with KT150 tubes. So it could be call whatever because it will handle KT170, KT150, 6550, EL34, 807, etc.

This amp design is different from Ultimate. This amp will use 6EM7 as drivers. Heavy duty drivers. Bigger power supply and will use 5 volt rectifier. Bias for the power tubes will be fixed, i.e. I have to manually set it. So I can set KT88 to 60mA and EL12 spez to 50mA, etc.

I will be doing the test with Susvara and HD800. Part of the purpose of my test is to see if GEC 807 ATS25 or VT60 will sound better in this KT170 amp or Ultimate. I will be doing the same with the other power tubes - 6550, EL34, EL39, EL38, etc. Ultimate is auto bias and we know that 807, EL39, EL12 spez sound great in Ultimate but will it sound better in the fixed bias KT170 amp. This will be one of the main focus of my test.

Lastly, as the KT170 amp is a speaker amp of about 11 watts, I will test it driving my speakers - both bookshelf and floorstanders. Both are Axis Technology speakers made by John Reilly, the man with the golden ears. John was in my living room btw and we were listening to Led Zeppelin 'Stairway to heaven' with the speakers made by him or his workers. His design. This was several years ago.

The Axis speakers in my lounge.

Looking forward to hearing your thoughts

 

[UntilThen]

Looking forward to hearing your thoughts

It’s fast track now. I am picking up the amp tonight. UntilThen lives in a fast pace world.

 

[UntilThen]

This is going to be a very long night. I will probably be seeing the sunrise.

Ok, let's start again. This is the KT170 Silke amp. More than 10 watts into 4 ohms. Speaker outputs have 4 and 8 ohms. It is not a new amp but it is the standard extension of the 6L6GC timE or SilkE amp. It is working at about 220v - 350v high tension. It is adjustable fixed bias so users can set the bias for power tubes for optimization. For KT170, I've set the bias to 70mA as instructed by Eric. He ask to me to compare setting to 60mA vs 70mA. That will happen tomorrow. For now it's set to 70mA.

The input / driver tube is the wonder tube 6EM7 / 6FD7 / 6DR7, using direct coupling between it's dual dissimilar triodes.

The amp sounded a bit edgy, being new but the power is awesome. I've never heard Susvara being driven this way before. It's gutsy, forceful and just dynamite. Involuntarily my head started bobbing and my feet started tapping. Treble is super clear, bass is jaw dropping and the midrange will entice you. Soundstage is super wide. This KT170 amp is doing to Susvara what Ultimate is doing to HD800. I am using speaker taps headphone cord. With Susvara, the volume is sitting at only 10am for really loud listening. Any louder and the ears will get damage.

I'm almost certain that I want this KT170 amp and I will call it Hercules.

Side by side with Ultimate. This is my initial rumbling. I'm just so engrossed with what I am hearing. It's just song after song. I couldn't stop.

Edit:- Coupling caps is Russian k40y-9.

2nd edit:- It is super quiet with HD800 and Susvara. This came as a surprise to me.

3rd edit:- If I get this amp, it will definitely have headphone outputs at the front just like Ultimate.

 

[crakers7]

This is going to be a very long night. I will probably be seeing the sunrise.

Ok, let's start again. This is the KT170 Silke amp. More than 10 watts into 4 ohms. Speaker outputs have 4 and 8 ohms. It is not a new amp but it is the standard extension of the 6L6GC timE or SilkE amp. It is working at about 220v - 350v high tension. It is adjustable fixed bias so users can set the bias for power tubes for optimization. For KT170, I've set the bias to 70mA as instructed by Eric. He ask to me to compare setting to 60mA vs 70mA. That will happen tomorrow. For now it's set to 70mA.

The input / driver tube is the wonder tube 6EM7 / 6FD7 / 6DR7, using direct coupling between it's dual dissimilar triodes.

The amp sounded a bit edgy, being new but the power is awesome. I've never heard Susvara being driven this way before. It's gutsy, forceful and just dynamite. Involuntarily my head started bobbing and my feet started tapping. Treble is super clear, bass is jaw dropping and the midrange will entice you. Soundstage is super wide. This KT170 amp is doing to Susvara what Ultimate is doing to HD800. I am using speaker taps headphone cord. With Susvara, the volume is sitting at only 10am for really loud listening. Any louder and the ears will get damage.

I'm almost certain that I want this KT170 amp and I will call it Hercules.

Side by side with Ultimate. This is my initial rumbling. I'm just so engrossed with what I am hearing. It's just song after song. I couldn't stop.

Edit:- Coupling caps is Russian k40y-9.

2nd edit:- It is super quiet with HD800 and Susvara. This came as a surprise to me.

3rd edit:- If I get this amp, it will definitely have headphone outputs at the front just like Ultimate.

Interesting , so you prefer this amp tonally over the 300b amp ?

 

[UntilThen]

Interesting , so you prefer this amp tonally over the 300b amp ?

I do actually. KT170 SE amp has more linear extension and sweeter treble than the 300b amp. @xtiva is coming over today to have a listen. Another Susvara user. However I suspect that there will be fans of both camps. Best is if you have both.

This amp has triode and ultralinear mode. I'm still on triode mode. Haven't got to UL yet. That will give more power. As if more power is needed.

 

[UntilThen]

Trying GEC 807 VT60 on Hercules now. Gawd I hate that name. It's only temporary. It's not a permanent name. I bias it to 50mA. You can see the volume knob is at slightly above 9am with Susvara. This amp has monster power. I have not heard Susvara moved so much. When I first heard Susvara with WA33 in 2017 at Addicted To Audio booth at the Sydney HiFi show, I was literally star struck with how deep and visceral the bass sounded. However Susvara on Hercules is even more amazing.

GE 6EM7, GEC 807 VT60, Miniwatt GZ34 made in Sittard Holland.