[mithrandir38]

So how does the Encore compare to the original?

It has the same tonality as the original, but slams a bit harder with the optional input transformers. It's a bit quiet than the original. The dual inputs are a godsend, and it sounds great as a preamp. In short, everything that was good about the Kenzie is improved on the Encore.

 

[JoeDoe]

It has the same tonality as the original, but slams a bit harder with the optional input transformers. It's a bit quiet than the original. The dual inputs are a godsend, and it sounds great as a preamp. In short, everything that was good about the Kenzie is improved on the Encore.

I gotcha. Thanks for your thought's!

 

[JoeDoe]

Well, as of last night, it's settled. I've got a Kenzie with upgraded caps in the build queue! Decided to build an endgame rig for my PS1000's and I think it'll be the Kenz with a Neko D100ii DAC.

Had the Leeloo for a short time and loved it, but had to part with it prematurely. Hoping that I can liquidate some of my other gear before the Kenzie gets here!

 

[desik]

Anyone got a chance to compare Kenzie Encore with something else same price range, like Zana Deux?

 

[desik]

@mithrandir38, did you have a chance to compare your amp with something else?

 

[mithrandir38]

@mithrandir38, did you have a chance to compare your amp with something else?

Just my Mjolnir 2 amp, which I sold to a friend on another site. I prefer the all tube sound of the Encore. I'll a have a review up on the coming weeks

 

[cute]

Those are different adapters. You need separate adapters for 5755 and 12ax7 types

Could you please post, or link to the exact Sovtek 12AX7 that you are using?

Thanks

 

[ampsandsound]

The Sovtek is likely they 12AX7LPS. Has long plates and spiral filaments. Great sounding tube and won’t break the bank.

 

[cute]

The Sovtek is likely they 12AX7LPS. Has long plates and spiral filaments. Great sounding tube and won’t break the bank.

Thanks Justin! Hey I sent you an email asking about outboard transformers for my Kenzie. Mine is a few years old, would it benefit my unit?

Thanks

 

[Elzizo]

http://ampsandsound.com/

Mogwai

Like many of our products, the Mogwai evolved from our earlier designs, borrowing from the Bigger Ben and Classic Wonder, while embracing the form factor of the Kenzie. The Mogwai offers more than an entry point for tube amps, but a hybrid product, meant for serious headphone and speaker use.

Our circuit offers the ability to roll a wide variety of tubes inexpensively and bring increased power to headphones without any sacrifice of design choices that conflict with our values.

The Mogwai combines the features of a full sized amp into a small amplifier package, weighing ~15lbs largely due to its over spec’d custom wound transformers. The Mogwai utilizes Single ended Class A operation with zero feedback to provide the essence of our Classic Wonder sound; strictly old school SET sound, while paired with a more accessible tube selection.

The performance of the Mogwai is made possible with custom wound ultra-high quality output transformers from Transcendar Transformers providing amazing frequency extension and flat response.

The Mogwai does not use a voltage divider network, but depends on transformers instead. We chose 32ohm tap for headphones to offer a dedicated selection for the widest range of headphones, and an 8ohm speaker tap to connect the Mogwai to moderately efficient speakers.

The Mogwai displays its transformers prominently on the chassis to frame in the tube selections, which can vary from a 6L6GC to a KT88.

Volume control is handled by the ALPS volume pot to allow attenuation and simplify the signal path… no preamp is needed. Zero feedback on the outputs negates the need for a pre, an iPhone can drive the Mogwai without issue.
The Mogwai differs from the Kenzie as it aims to provide powerful output while remaining true to 50s tube ideals, and single ended sweetness. As with all ampsandsound products, we strive for a neutral, non-fatiguing sound, and demand that all our products be ultra-quiet in operation. Quiet operation is not just a goal but a guiding principle that shapes all design and implementation choices… from pots to resistors we strive for tube amps to never distract from the music.

Input tube: 6SL7 or equivalent
Output tubes: 6L6GC, EL34s, KT66, KT77, KT88, 6550s and KT90s
Personal favorite is the TungSol 6L6GC STR. Warm, strong and tight bass.
Cathode Bias/automatic bias allows for easy tube changes without adjustment.

Compatible with 32ohm-300ohm headphones using the “32ohm” 1/4″ jack. (Beyerdynamic T1-600ohm were used successfully but not ideal.)

Headphones driven successfully or tested with the amp include, Mr. Speaker Ethers, Mr. Speaker Ether Cs, Audeze LCD-2.2F, Audeze LCD-XC, AKG240, AKG701, Sony MDRV6, Sennheiser HD650, Sennheiser HD800, Beyerdynamic T1-32ohm, HIFIMAN HE400i.

The Mogwai is made with pride in Southern California with US sourced parts, including our precision transformers.

Specs:
Input impedance is 250Kohm with alps pot, .5v for full power.
Noise with pot fully counterclockwise is 500 micro volts RMS
Measured with 6550 output tubes on 1/4″ 32ohm optimzied headphone jack. 500mW RMS output 20 Hz (-2db) to 17.7 kHz (-3db)
Measured with 6550 output tubes on 8 ohm tap. 3W RMS output 30 Hz (-1db) to 20 kHz (-2db)

Please look at our news section for feedback from owners of the Mogwai.
Mogwai Headphone amp – $1,700 with tube set.

Kenzie Headphone Amp

Like many of our products, the Kenzie Headphone Amp evolved from our earlier designs – in this case, rave reviews about the SE-84’s headphone section. The inevitable question followed; why didn’t we build a dedicated headphone amp?

Why indeed? After some research, we came to the conclusion that the Kenzie amp using the much loved darling circuit was the right choice for us. The outstanding performance of the Kenzie Headphone amp is made possible with custom wound ultra-high quality output transformers providing amazing frequency extension. The Kenzie does not use a voltage network, and has more than enough power to drive even the most difficult headphones. We chose 32ohm and 600ohm to allow use with the widest variety of headphones.

The Kenzie Headphone amp showcases the transformers on the chassis to frame in the amazing 1626 tubes in all their single-ended direct-heated bliss. We have included an ALPS volume pot to allow attenuation and simplify the signal path… no preamp is needed.

The 1626 AKA Kenzie is one of the sweetest-sounding amps you will ever hear. The 1626 is commonly referred to as the poor man’s 300b; all the same great imaging, texture, and single-ended sweetness without the cost to break the bank.

The 1626 is a WWII era tube used as a transmitter tube in radar installations. The design is shy on pure output, but is overflowing with texture and drive, and is paired with a massive choke and robust output transformers for ultra-quiet operation. As with all of our products, parts selection was crucial during this build and each chosen not for price, but for best quality and synergy.

Input tube: 12SL7 or equivalent
Output tubes: 1626 or VT-137 which is a WWII transmitter tube and characterized as sounding like a mini 300b.
Cathode Bias/automatic bias allows for easy tube changes without adjustment.
Compatible with 32ohm-300ohm headphones using the 32ohm 1/4″ jack.
Headphones above 300ohms will benefit from using the 600ohm 1/4″ jack.
Headphones driven successfully or tested with the amp include, Mr. Speaker Ethers, Mr. Speaker Ether Cs, Audeze LCD-2.2F, Audeze LCD-XC, AKG240, AKG701, Sony MDRV6, Sennheiser HD650, Sennheiser HD800 (though reduced volume), Beyerdynamic T1-600ohm, HIFIMAN HE400i.

The Kenzie is made with pride in Southern California with US sourced parts, including our precision transformers.

Specs:
Input impedance is 250Kohm with alps pot, .5v for full power.
Noise with pot fully counterclockwise is 5mV RMS (Average)
All measured at 32 ohm tap. All power measurements in RMS
100mW 20 Hz (-1db) to 17.7 kHz (-3db)
150mW 20 Hz (-1db) to 14.8 kHz (-3db)
200mW 20 Hz (-1.25db) to 16.7 kHz (-3db)

Please look at our news section for feedback from owners of the Kenzie Headphone amp.
Kenzie Headphone amp – $1,500 with NOS tube set.

Gizmo

I picked up the Mogwai that was at CanJam SoCal. Really loving it! These amps deserve their own thread. I'd post a pic of it, but it's the one on the website and the pictures are way better than what I can take.

Since I bought the prototype, I'm claiming the right of prima nocta... or something... and nicknaming my Mogwai "Gizmo."

Reviews

Kenzie Headphone Amp

Positive Feedback
Headphone.Guru
mithrandir38
joespride

Thank you for taking to time to put this together. I for one appreciate your efforts!

-Elzizo

 

[Luckbad]

Thursday
I'm listening to Justin's personal Mogwai Special Edition at home right now. The Mogwai holds a special place for me as my first big boy tube amplifier and I've always had nostalgia for its musicality.

@ampsandsound can correct me if I'm wrong, but I believe this particular unit is running with:

• Two inputs (with a switch to swap between them on the fly). One with an input transformer, one without
• Wima capacitors (not the upgraded caps)
• A badass Mullard 5AR4 rectifier
• Input (driver) tube looks to be a JJ 6SL7
• Power (output) tubes are Tung-Sol 6L6GC STR
• 32 ohm & 300 ohm headphone outs, 8 ohm speaker taps
• Rosewood casework (don't think this is normal--it's his personal unit)

The tube complement is going to influence a lot of my impressions because this type of amplifier is dramatically influenced by the tubes. That said, it's still pretty easy to judge you'll enjoy an amp with just about any decent tube, and the tubes in here are pedestrian but known for their reliability (with the exception of the rectifier, which is balls-to-the-wall outstanding and costs ~$200).

My initial impressions were using the Sennheiser HD650 from the 32 ohm output and the input with the transformers.

And what a first impression the Mogwai SE makes!

The musicality is incredible. The deep, slamming bass is better than I've ever heard on the HD650s. Soundstage depth is very good, width is good. The background is very quiet with these cans--much quieter than my original Mogwai was, that's for sure.

With the RME ADI-2 DAC it's pretty easy to compare two different inputs. I had one output from the headphone out in front and the other output from the line outs in back. To maintain volume control (because either the ADI-2 DAC's output levels are different between the two or the inputs on the Mogwai SE are at different volumes, not sure which), I kept it in a mode that lets me press the volume button (or a remapped key on the remote) to switch between line and phone out.

I quickly came to the conclusion that the input with the transformer(s?) is better. Unfortunately, that's something like a $400 option, but hey, it's better in just about every way to my ears.

Testing between the 300 ohm and 32 ohm outputs is a little tougher because they output at different volumes, but I'm pretty sure I prefer the 32 ohm output. I don't have the necessary cables to convert the 8 ohm speaker taps to a 1/4" out so I don't get to test that.

This amp reminds me of why I was swept off my feet at the CanJam meet a couple years ago when I originally bought a Mogwai. It is raw musicality. This latest version doesn't want for detail and fulfills all of the audiophile checkboxes in my book.

It does not pair wonderfully with the Audeze LCD2 Classic. Those headphones need lower output impedance and might do well from the 8 ohm taps.

The ZMF Auteur, on the other hand, sounds lovely. I'm pretty unfamiliar with this headphone but first impressions are very good when paired with the Mogwai SE.

The Mogwai Special Edition is the sort of amplifier that makes you want to saturate paragraphs with hyperbole.

I'm tired of typing and going to relax into the amp for the rest of the night.

Three Days Later...
I spent a little more than the weekend with the ampsandsound Mogwai SE. As I mentioned earlier, its tube complement was a high end rectifier and the other 3 tubes were fairly common new production tubes. I didn't tube roll, so my experience is based exclusively on those.

After the weekend, I've come to the conclusion that I've never heard a better amp for the HD650s. It drove them with more authority than anything I've owned or encountered for any real period of time (no, I've never heard the Aficionado).

My limited memory of the pre-production DNA Stellaris (when it was the Super Stratus) is that it has similar tonal characteristics to that, which puts it in a similar playing field to the Stratus (which I haven't heard in good conditions, but I loved what I heard from that).

Compared to the Eddie Current Super 7--from memory but with the Liquid Crimson as reference and Orchid as a familiar DAC--it hits considerably harder. It has a similar wetness and musicality, but may very well outresolve it. Mine was minimally modified (decent but not great film capacitors, nicer wiring, good RCA jacks).

I noted this previously, but it's the sort of amp that makes you prone to hyperbole. It has an ineffable quality to it. It's euphonic, musical, and joyous. The Mogwai SE is an amplifier that you plug into and can't help but crack a smile. It's the warm fire and cocoa on a cool winter night. It wraps you up in the music.

Perhaps the highest compliment you can pay to a piece of audio gear is that you just want to keep listening as you get lost the music. That's what the Mogwai Special Edition accomplishes.

It's not as clean as the Liquid Crimson. It doesn't manage the same level of microdetail and microdynamics. But it has a magical quality to its presentation that makes it more alluring a listen.

The unit I had here was equipped with two inputs. One had a pair of transformers (one per channel), and the other input did not. I preferred the transformer-coupled input without question. It was cleaner yet more authoritative. In fact, I'm really curious about the effect of inputs transformers on other amps and might ping Justin to see if I can get some outboard input transformers to find out.

High impedance dynamic headphones like the Sennheiser HD650 and ZMF Auteur were utterly outstanding from the 32 ohm output. I didn't love the Sennheisers from the 300 ohm output, as it crept some of the upper bass toward the mids and seemed to smear things a little more to my ears. The Auteurs fared a bit better at 300 ohms.

I also do not think it played nicely with the Audeze LCD2 Classics. You need a lower output impedance amp with those, it seems. They became a bit bloated and glossed over. I wish I had an adapter to try the 8 ohm speaker taps with the Audezes or Sennheisers.

With the Orchid, the Mogwai SE became too much of a good thing. It was too wet, too smooth, too bloomy. With the RME ADI-2 DAC using a filter without much rolloff (e.g. SD Sharp), it was outstanding. Folks like atomicbob espouse system synergy for a reason.

Compared to the original ampsandsound Mogwai, the Mogwai is basically a little better in every way. More moarness. Ergonomically, it's also considerably better. The headphones outs up front make things much less awkward.

This is very late in the comment to note this because for some reason I've been taking for granted that people know some things about the amp but...

General characteristics of the Mogwai Special Edition:

• Full, layered, impactful bass
• Rich, luscious mids
• Smooth yet somewhat airy treble
• Engagement is favored without sacrificing much detail, clarity, or dynamics
• Soundstage approaches "spooky" levels similar to Eddie Current (though EC still performs this magic slightly better)

So did I buy one? No, not yet.

Reasons? Sure...

• Price: It's above my self-imposed limit of $2000 for an amplifier. Maybe if one happens to show up used below that cutoff.
• Versatility: I have lower impedance headphones as well as IEMs. The Liquid Crimson does great with those, but the Mogwai is especially well-suited to high impedance dynamics.
• Tube Nervosa: Some of you saw what happened when I had 7 tubes to choose in the Super 7... it quickly gets stupid and I acquire a pile of tubes and stop enjoying the music.

If I had room in the budget for an amp to specifically pair with my modded Sennheiser HD650s, I'd already have an order in with ampsandsound.

 

[omniweltall]

Great review! Really enjoyed reading it.

Luckbad is certainly one of few ears I trust here. He gives objective reviews and has experience to review gears.

 

[zach915m]

Thursday
I'm listening to Justin's personal Mogwai Special Edition at home right now. The Mogwai holds a special place for me as my first big boy tube amplifier and I've always had nostalgia for its musicality.

Great write up I couldn't have said it better!

We will have a Mogwai SE at our booth at CanJam NYC with a very similar configuration (same amp diff tubes) as @Luckbad is checking out right now. It is incredible how the Mogwai manages impact, weight and musicality while not sacrificing linearity and extension. It's a cool experience.

 

[dunkyboy]

Just wanted to post my [long, ongoing] Mogwai SE story.

I bought ZMF Eikons last August, hoping they’d be the end of my search for the perfect closed-back headphones, for the office. (I also bought a pair of Atticus to compare, but decided they weren’t for me.) They came so close to perfection that I’ve been on a follow-up search for the perfect amp for them!

I found my Schiit Lyr lacking, even with rolled tubes. My Chord Mojo drove them pretty well on its own (better than the Lyr, though with less raw power), but with a persistent grain and lack of sweetness & air in the treble. I suspected the high-impedance Eikons weren’t mating well electrically with the low-output-impedance solid state amps.

So I bought a Valhalla 2, hoping the all-tube design would work better with the 300-ohm Eikons. It definitely sounded better than both the Lyr and Mojo, bringing some of that sweetness and air to the treble, and some nice mid tones. Stock tubes were quite bright, but with NOS Amperex Orange Globes, the brightness was tamed and the sound was natural and slightly warm. It lacked a bit in dynamics, but sounded good overall, especially for the price. I thought I’d leave it at that for a year or two, when I might be able to justify an upgrade into $1000+ territory, maybe Zach’s recommended Decware CSP.

But whenever I listened to my home system (rarely now, with 1yo twin boys running around), a dream all-Audio Note system (DAC3 into Oto Phono Signature driving AN-E HE LX), my Eikon rig sounded clearly “mid-fi”… Everything - resolution, tonal color, dynamics, frequency extremes, soundstage - was good, but not where I wanted it to be.

And then CanJam came to NY… I brought my Eikons and tried them with every amp I could, hoping to determine whether it was the amp that was holding the Eikons back, or whether the Eikons themselves were limited.

I quickly learned that the Eikons benefitted hugely from higher-end amps, but I didn't hear anything that blew me away until I got to the ZMF table, where I ended up spending most of my time at the show listening to Eikons driven by Zach’s Ampsandsound Mogwai SE, with some choice NOS tubes rolled in. The combination was spellbinding! All the technicalities were superb, but more importantly (and like my Audio Note system), it just sounded *right* - like real instruments and voices playing real music. You just forgot about the reproduction chain and got lost in the music… The Eikons could really soar! *This* was what I wanted!

But it was $2500. Waaaay out of my budget!

But I couldn’t stop thinking about that listening session, and how much I wanted that sound. So, in a fit of financial recklessness (and with the help of PayPal Credit…) I bought it anyway.

It arrived last Friday, and I’ve spent most of my last two workdays listening to it (this is my office system). Source is a MacBook Pro into Chord Mojo, which is a fantastic little DAC.

Even [literally] cold, it was clearly a whole new ballgame from the Valhalla (as it should be of course, costing 7x as much!!) Huuuuge, wide open soundstage; rich, textured mids; sweet treble; thunderous, deep, clean bass. I did find it a touch on the warm side for my tastes, and that warmth seemed to obscure some detail. So after a couple hours of listening, I rolled in a NOS RCA 5U4GB rectifier tube that Zach recommended (the same one in his Mogwai SE at CanJam). That really brought it to life, bringing the treble out, and adding to the overall clarity and openness. It’s still a little warm, but not overly so, and I enjoy it that way.

I’ve already got the driver tube Zach recommended (again, from his CanJam setup) on order, an RCA 6SL7 - should arrive tomorrow. I’m holding off on getting the power tubes he was using (GEC KT8C with adapters) as they’re $250..! I’m hoping with the RCA rectifier and driver tubes in place, I’ll be happy for now..!

One other interesting thing to note is the difference between the 32-ohm and 300-ohm jacks, with the Eikons. The 32-ohm sounds tighter, more focused, denser, and a bit more midbass-forward, but I much prefer the 300-ohm - it sounds huge and expansive, with a lighter, more natural balance, with vocals more forward in the mix. It’s frankly spooky how good the soundstage is - sounds come out of nowhere and seem to hang in the air around your head! Love it.

So anyway, given the NOS rectifier and the 300-ohm tap, how does it sound currently? In a word, phenomenal! I had no idea the Eikons could sound so good - they’re clearly the best closed-back headphones to me (although the Sennheiser HD820s I heard at CanJam were excellent, but that’s another story - also they’re $1000 more!)

This is going to devolve into gushy word soup, but here goes… The sound is huge, open, unrestrained, and totally natural. Detail is present in spades, but isn’t thrust in your face or etched - it sounds like the real thing. Treble is sweet, silky smooth, crisp, sparkly, and airy - this is the best treble I’ve heard from a headphone, open or closed. Mids are slightly warm, but not overblown - beautiful and natural. Bass is huge, clean, tight, punchy, and deep. Tones and textures are dense and rich. The sense of scale, on music that has it, is immense, combining that huge soundstage, huge power, huge dynamics, and deep, punchy bass!

It never seems to run out of steam either… I was playing tracks on shuffle, and at one point went from a Vivaldi choral piece - mixed very low, so I had the volume cranked up - to Caribou’s “All I Ever Need”… the bass kick made me jump! And I'm find myself gradually turning the volume up and up over time while listening - usually a good sign (though maybe not for my hearing).

Anyway, I just wanted to add my voice to the chorus of praise for Ampsandsound’s amps, and the Mogwai SE in particular. If you can afford the frankly eye-watering price of entry, you’ll be richly rewarded - especially if you’re up for a little tube rolling! I found it interesting to learn how much entry-level amps were holding back the EIkons - it’s really a credit to ZMF that they scale so well. I honestly think they’re among the best closed-back headphones you can buy.

I’ll update when the 6SL7 arrives, and also if I do end up taking the plunge for those KT8Cs…

 

[ampsandsound]

Ok. Here is my secret sauce tubes. 5U4 NOS. Pref RCA and a 6889 with adapter. These are the most impressive tubes I’ve ever seen. Not the last word in power but some of the tightest bottem end possible.