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Other Stuff => Archived Manufacturer Circles => Wolf Ear Audio => Topic started by: tdinut on 20 Nov 2018, 10:50 pm

Title: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: tdinut on 20 Nov 2018, 10:50 pm
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?



Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tomy2Tone on 24 Nov 2018, 04:25 am
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
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Wolf Ear Audio on 15 Jan 2019, 10:43 pm
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.
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Wolf Ear Audio on 15 Jan 2019, 10:47 pm
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).
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Shogun on 16 Jan 2019, 03:33 am
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.triodelab.com/)

http://www.finaleaudio.com/ (http://www.finaleaudio.com/)

For Andrew, may I suggest a KT150 SE integrated amplifier. There's only a few of these design around.
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Wolf Ear Audio on 16 Jan 2019, 05:27 pm
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.triodelab.com/)

http://www.finaleaudio.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 :)
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Shogun on 17 Jan 2019, 12:51 am
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 :D. 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.  :D
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Wolf Ear Audio on 17 Jan 2019, 06:51 pm
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 :D. 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.  :D
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 :)
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tyson on 18 Jan 2019, 04:44 pm
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. 
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tomy2Tone on 18 Jan 2019, 10:04 pm
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?
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tyson on 18 Jan 2019, 10:13 pm
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. 
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tomy2Tone on 18 Jan 2019, 10:17 pm
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 15ā€ driver to push. Thanks for your thoughts
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tyson on 18 Jan 2019, 10:26 pm
Nice, my klipsch speakers are 101db but do have a 15ā€ 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. 
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tomy2Tone on 18 Jan 2019, 10:33 pm
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 15ā€ 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 Iā€™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
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Wolf Ear Audio on 23 Jan 2019, 05:02 pm
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?  8) ).


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 :D. 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 :)
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tyson on 23 Jan 2019, 10:44 pm
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. 
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Shogun on 24 Jan 2019, 01:06 am
Very promising and tempting. 30w in SE :D, 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.
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Wolf Ear Audio on 24 Jan 2019, 02:24 am
Very promising and tempting. 30w in SE :D, 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?
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: mresseguie on 24 Jan 2019, 03:16 pm
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
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tyson on 24 Jan 2019, 03:51 pm
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).
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Wolf Ear Audio on 24 Jan 2019, 04:40 pm
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
For the stepped attenuator the audio curve I designed on this one is similar to the Alps Blue Velvet potentiometer audio curve. It averages about 2db between each step and it is more accurate, but theres no reason I couldn't use a potentiometer (smooth volume control) if you prefer. More steps mean finer control but I would still use the same audio curve.
Dimensions would be the similar to the Kitoki, but the output and mains transformer would be on top for size reasons.
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Tomy2Tone on 24 Jan 2019, 04:58 pm
For the stepped attenuator the audio curve I designed on this one is similar to the Alps Blue Velvet potentiometer audio curve. It averages about 2db between each step and it is more accurate, but theres no reason I couldn't use a potentiometer (smooth volume control) if you prefer. More steps mean finer control but I would still use the same audio curve.
Dimensions would be the similar to the Kitoki, but the output and mains transformer would be on top for size reasons.

Hi Andrew, do you offer a remote for volume control if requested?
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Wolf Ear Audio on 24 Jan 2019, 07:16 pm
Hi Andrew, do you offer a remote for volume control if requested?
Not at the moment. I'm not sure if I will for some time, but if demand is high enough I would look into it.
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Nidri17 on 25 Jan 2019, 05:06 pm
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).

Indeed.

In addition to the models already mentioned, I found this Italian-made design offering 30wpc from 2 x KT150's:

https://www.gabrisamp.it/negozio-online/nuovo/calypso-kt150/

This goes for $2,500+ (equivalent) - as another point of comparison.
It's pretty big (380mm x 460mm x 210mm).
Quite heavy at almost 60lbs (27kg).
& Doesn't offer Triode/UL switching either.

The projected specs for the Wolf Ear seem more attractive to me.
More versatility, lower weight, etc.

(Just my impression, I'm not making any assumptions or claims about the sound quality of either product.)
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Wolf Ear Audio on 5 Feb 2019, 08:23 pm
Indeed.

In addition to the models already mentioned, I found this Italian-made design offering 30wpc from 2 x KT150's:

https://www.gabrisamp.it/negozio-online/nuovo/calypso-kt150/

This goes for $2,500+ (equivalent) - as another point of comparison.
It's pretty big (380mm x 460mm x 210mm).
Quite heavy at almost 60lbs (27kg).
& Doesn't offer Triode/UL switching either.

The projected specs for the Wolf Ear seem more attractive to me.
More versatility, lower weight, etc.

(Just my impression, I'm not making any assumptions or claims about the sound quality of either product.)
Alright, I'm thinking about going ahead with this design but I'm still a bit unsure. It would likely replace my Makoyi as far as headphone amps go while also filling a gap for integrated speaker amps.
I only have parts for a few Makoyi amps left so this would be an easy enough decision for me (I can also give a decent discount to any of our Audio Circle members to help clear out stock as well, just e-mail or message me).
If I do commit to doing a small batch of this new amp (10-25 completed amps) I may have to do a Kickstarter or similar in order to fund the production of it since the transformers, tubes and general parts for this design are going to be very costly for me.
Or I could sell them semi-custom amps like I already do with the Makoyi and Natayo, but that would increase the price since I wouldn't get the same kind of bulk discounts. I would be interested in knowing what people would prefer :)
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: 15invo on 6 Feb 2019, 05:04 pm
I'll  be interested in the kickstarter !
Title: Re: Any chance we'll see a 45, 2A3, 300B or similar amp coming in the future?
Post by: Greydogs on 3 Feb 2021, 03:49 am
Hi,
I recognize this is an old thread, but is there any chance this integrated KT150 amp will be released? Sounds like a great idea. Icon audio has a similar KT150 amp, but this amp sounds great in price and features.