[tdinut]

I only ask because I need just a few watts, but would love a very typical SET sound.


Build quality here looks wonderful and am excited to see Andrew succeed.




How difficult would it be to modify the design for one of the above tubes?

[Tomy2Tone]

I only ask because I need just a few watts, but would love a very typical SET sound.


Build quality here looks wonderful and am excited to see Andrew succeed.




How difficult would it be to modify the design for one of the above tubes?

+1

[Wolf Ear Audio]

I only ask because I need just a few watts, but would love a very typical SET sound.


Build quality here looks wonderful and am excited to see Andrew succeed.




How difficult would it be to modify the design for one of the above tubes?

Sorry for being late to respond. I am now active on my forum again after some serious health and personal issues, so I would like to respond now even though it is late.
An amp like this is very possible, but not with the current design. If designing for the 45, 2A3 and 300B tubes I would like to have regulated DC supplies for each tube since I am very picky about noise (not really an issue with indirectly heated tubes like in the Kitoki, but directly heated tubes like those would have a lot more noise with an AC heater like the Kitoki uses).
I am not opposed to building an amp for those tubes, but it would likely be a very limited run since I expect the cost to be much higher vs building the Kitoki V2, which was designed with high value in mind.

[Wolf Ear Audio]

If there's enough interest in this idea I would love to flesh it out, maybe into either a power amp or monoblocks. Or maybe even an integrated with both speaker and headphone outputs (but I'm probably getting a bit too ahead of myself here lol).

[Shogun]

I only ask because I need just a few watts, but would love a very typical SET sound.


Build quality here looks wonderful and am excited to see Andrew succeed.




How difficult would it be to modify the design for one of the above tubes?

There's already a manufacturer that I'm sure will meet your expectation for a triode tube. It's Triode Lab and its sister company. Top notch sound, build quality and support if needed. My first choice if I ever want SET or a EL84 (Finale Audio 7189 mk2).

http://www.triodelab.com/

http://www.finaleaudio.com/

For Andrew, may I suggest a KT150 SE integrated amplifier. There's only a few of these design around.

[Wolf Ear Audio]

There's already a manufacturer that I'm sure will meet your expectation for a triode tube. It's Triode Lab and its sister company. Top notch sound, build quality and support if needed. My first choice if I ever want SET or a EL84 (Finale Audio 7189 mk2).

http://www.triodelab.com/

http://www.finaleaudio.com/

For Andrew, may I suggest a KT150 SE integrated amplifier. There's only a few of these design around.

That's a pretty monstrous tube with some pretty serious potential power output. In SET mode with a high B+ (400-500vdc) it could hit 10 watts output, or maybe over 20 watts in Ultralinear mode with a single output tube. Could be pretty fun

[Shogun]

For inspiration, look a these KT150 SE.

Denis Had Fire Bottle KT150, 10-12w
Icon Audio Stereo 30 SE, 18-28w, UK
Lab12 Suono, 25w, Greece
Dared Saturn, 25w, China

What I want to see is: 25w, triode-UL switch, 2000us max and Wolf Ear Audio build quality . 25w from KT150 SE is to be able to power real world loudspeaker with the sound of a single ended class A, but without the price of a 811/845 tubes.

There's a market for that type of amplifier. For what ever reason, nobody here, in north america, is making them. Dennis Had is retired and he's not making them on a constant basis. Maybe Wolf Ear Audio can fill this gap. 

[Wolf Ear Audio]

For inspiration, look a these KT150 SE.

Denis Had Fire Bottle KT150, 10-12w
Icon Audio Stereo 30 SE, 18-28w, UK
Lab12 Suono, 25w, Greece
Dared Saturn, 25w, China

What I want to see is: 25w, triode-UL switch, 2000us max and Wolf Ear Audio build quality . 25w from KT150 SE is to be able to power real world loudspeaker with the sound of a single ended class A, but without the price of a 811/845 tubes.

There's a market for that type of amplifier. For what ever reason, nobody here, in north america, is making them. Dennis Had is retired and he's not making them on a constant basis. Maybe Wolf Ear Audio can fill this gap. 

Hey, I think that may just be doable. I'll have to see about finding a supplier for KT150 tubes, but I'll draw up a schematic over the weekend and see what I can do

[Tyson]

KT150 is actually a very nice sounding tube.  I can run it in my Dennis Had Inspire SEP amp and it's a big/bold sounding tube.  Maybe not as refined as a NOS 6550 or KT88 but it has a better sensed of drive and slam, while still sounding pretty sweet. 

[Tomy2Tone]

KT150 is actually a very nice sounding tube.  I can run it in my Dennis Had Inspire SEP amp and it's a big/bold sounding tube.  Maybe not as refined as a NOS 6550 or KT88 but it has a better sensed of drive and slam, while still sounding pretty sweet.

Hey Tyson, if you had your choice would you rather listen to a kt150 tubed amp or a 45 tubed amp?

[Tyson]

Hey Tyson, if you had your choice would you rather listen to a kt150 tubed amp or a 45 tubed amp?

Depends on the speaker.  If it's a speaker with an active bass section and an easy load for the mids/highs like my Serenity Acoustic Super 7s, then I'd probably lean to the 45.  On the other hand, if it's a full range passive speaker, like my Klipsch Heresy IIIs in my 2nd system, I'd lean toward the KT150.  Even though the Klipsch are 99db efficient, they need something with real grunt and control to sound their best. 

[Tomy2Tone]

Depends on the speaker.  If it's a speaker with an active bass section and an easy load for the mids/highs like my Serenity Acoustic Super 7s, then I'd probably lean to the 45.  On the other hand, if it's a full range passive speaker, like my Klipsch Heresy IIIs in my 2nd system, I'd lean toward the KT150.  Even though the Klipsch are 99db efficient, they need something with real grunt and control to sound their best.

Nice, my klipsch speakers are 101db but do have a 15” driver to push. Thanks for your thoughts

[Tyson]

Nice, my klipsch speakers are 101db but do have a 15” driver to push. Thanks for your thoughts

I'm using an Almarro A318B on mine and it's a much better match than my 45 amp.  Big woofers in a box just need more headroom/power, IME.  One day I'll have to drag my Inspire monoblocks up to the main floor and try them out with the H3s.  For now though, I'm loving them with the Super 7s downstairs.  45 amp is sitting in the closet.  I never thought a great SE Pentode would be able to keep up with a SET, but indeed it's possible!! 

Back on topic, I bet a 20 Watt Ultralinear amp w/a KT150 would really bring your big Klipsches to life.  Hell, it'd probably sound great with a lot of speakers. 

[Tomy2Tone]

I'm using an Almarro A318B on mine and it's a much better match than my 45 amp.  Big woofers in a box just need more headroom/power, IME.  One day I'll have to drag my Inspire monoblocks up to the main floor and try them out with the H3s.  For now though, I'm loving them with the Super 7s downstairs.  45 amp is sitting in the closet.  I never thought a great SE Pentode would be able to keep up with a SET, but indeed it's possible!! 

Back on topic, I bet a 20 Watt Ultralinear amp w/a KT150 would really bring your big Klipsches to life.  Hell, it'd probably sound great with a lot of speakers.

I have the Pro series 396 speakers from klipsch and the 15” driver only goes to 60hz according to specs but does sound pretty good with my 845 set integrated that puts out 22 watts. Always wanted to try a 45 or 300b type amp but maybe I’m better off with more power. I do add in a couple Rythmik subs to go below 60hz but in my room I could get away without them.

https://f072605def1c9a5ef179-a0bc3fbf1884fc0965506ae2b946e1cd.ssl.cf2.rackcdn.com/product-specsheets/KI-396-SMA-II-Data-Sheet-v05.pdf

[Wolf Ear Audio]

Alright, so I drew up a schematic and these were the features/specs I wanted to include:

Output Tubes: 2x KT150
Input Tube: 1x 6SN7
Power (out):~ 12.5W (SET) / 30W (UL) per channel - (switchable)
Gain: ~20 (+26db)
Outputs: 4 ohm, 8 ohm and 16 ohm speaker outputs and headphones outputs (1/4" and 4-pin balanced) - (also switchable)
Inputs: 3 RCA - switchable
Input Impedance: 50K ohms
Output Impedance: ~1-4 ohms (depending on output used. The headphone output is ~4 ohms and the tap for 4 ohm speakers is ~1ohm)
Frequency Response: greater than 20hz-20khz @ +/-1db
Volume: 24-stepped series attenuator (built-in-house)
Weight: 30-40lbs
Notes: No negative feedback used. Entirely Class A (or Class Eh?  ).


I was thinking this could be used as a desktop amplifier because of the speaker and headphone outputs. It may have a lot of appeal to fans of mini maggies from magnepan, as well as owners of power hungry 'phones such as the HE-6, etc.

What I want to see is: 25w, triode-UL switch, 2000us max and Wolf Ear Audio build quality . 25w from KT150 SE is to be able to power real world loudspeaker with the sound of a single ended class A, but without the price of a 811/845 tubes.

Guesstimating the price based on what I currently pay for parts this would likely land under or near your 2000USD sell price with all these features. I would likely ship with all Tung-sol tubes as well.

I would love to make a product like this but would like to hear what you all think about it before committing to bringing such a project to life

[Tyson]

That looks amazing.  I'm not in the market for an amp (I have 5 already, haha).  But if I WERE in the market, this would be at the top of my list.  Single Ended, driven by the best sounding octal tube (6SN7) and up to 30 watts output, that's impressive. 

[Shogun]

Very promising and tempting. 30w in SE , KT150 sounds great and two of them are not expensive, the superior build quality based on your other projects and point to point wiring is easy to repair.

As they said, if you build it, they will come.

Just a suggestion, it would be great to make it compatible with other tubes like KT88. Just in case Tungsol can no longer make the KT150 tubes or the buyer already has the KT88.

[Wolf Ear Audio]

Very promising and tempting. 30w in SE , KT150 sounds great and two of them are not expensive, the superior build quality based on your other projects and point to point wiring is easy to repair.

As they said, if you build it, they will come.

Just a suggestion, it would be great to make it compatible with other tubes like KT88. Just in case Tungsol can no longer make the KT150 tubes or the buyer already has the KT88.

I thought about that, but that would be impossible given the design since most other tubes would not be able to handle the current bias and B+ voltage, so that would require a rework with lower voltages to make it compatible with other tubes and would result in an overall power loss and needing another switch for bias adjustment, etc.
Which would people prefer?

[mresseguie]

I'm asking this out of ignorance, so don't take it wrong, please.

Wouldn't the 24-step attenuator cause a big jump in volume with each step up? Would a 48 or 64-step control offer greater volume control?

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Separate question:

What would be the dimensions of such a case?

Regards,

Michael

[Tyson]

I thought about that, but that would be impossible given the design since most other tubes would not be able to handle the current bias and B+ voltage, so that would require a rework with lower voltages to make it compatible with other tubes and would result in an overall power loss and needing another switch for bias adjustment, etc.
Which would people prefer?

I think there's lots of good KT88/6550 amps out there already, and they're more limited in power.  I think the high powered KT150 fills a gap, particularly for people with more power-hungry speakers (ie, the vast majority of people).