Intg Amps: Hegel 590 vs NAD M33 Masters vs Gryphon Diablo 120

Hi All: I am getting an itch to upgrade my integrated amp from Hegel 190 to something more robust that facilitates future speaker swapping.  And no, I'm not presently interested in separating components that much further (e.g. separate DAC; separate amp; clock; etc. etc).  I mainly interested in the following 3 on a used basis:

Hegel 590 OR NAD Masters 33 OR Gryphon Diablo 120

Max budget is $7500 if I choose to go towards the Gryphon (used), but curious if it's really THAT much better.   I'm particularly interested to hear from people that have had or auditioned at 2 out of 3.  The room correction on NAD is very appealing but I quite like my Hegel and it's tight control, and so something nice about staying true.


Current Setup:

* Unideal Brooklyn Apartment living room into Kitchen

* Hegel 190

* Monitor Audio Silver 7G 500

* Pine Tree Audio Cables

* Dual 1216

* Schiit Mani 2 (though I hear the phono preamp on some of above may make this superfluous)

* Spotify/Tidal (main streaming source)


Of the amps you mentioned, I have heard two and they are very different. ( Hegel and NAD)  Great, but different. Unfortunately, it was an apples to oranges, different dealers and rooms listening.  I have a real soft spot for Hegel and not for NAD. The NAD is supposed to be a Purify, but I was not impressed. Maybe all the digital stuff in front. Don't know. Maybe I like the distortions from the Hegel. They were on Wilsons which are pretty good.  I heard the  NAD on B&Ws which I do not like at all. Don't get me wrong, both are serious great units. Just my preference. 

Your weakest link, kind of stretching to call it weak, is probably your RIAA stage. 

Do look at the actual bitrade of the files you are streaming. They may not be as good as you think. 

Have you considered an outboard DAC?  I am not sure the Hegel ( or NAD) internal is as good as it could be. Not bad, but not great. I auditioned the Hegel with a Qutest, the NAD with it's internal. 

Room correction can be critical, but do you need as complex as Dirac?  My room is too bright and being a LIVING room, no treatments are forthcoming. I put an Antimode on the sub ( single family so I can run a sub) but on the mains, I find just a traditional tone control to balance very nicely. My speakers are pretty flat in free space.  I could do that in JRiver, but I find some CDs I need to adjust a little so for now, old school tone control for the treble.  Your brain will "pattern" the room and unless things are really bad, fix a lot of EQ issues. You get used to it, or as the subjective reviewers say, the "electronics needs weeks to burn in". Really, it is their brain adjusting. Dielectrics form in hours, not weeks. 

I can contribute that I have owned the H590 and found it a formidable amp.  Plenty of power, a DAC that reviewers gush over, and Hegel's design philosophy that the amp should add nothing to the sound.  It is smooth and neutral.  I would look for one slightly used.  Only sold it when I decided to move up to the H30.  

In general in this pursuit you get what you pay for… particularly when you get to the ~ $7 - $10K or above. These are professionally designed, well reviewed and must be sonically of value or they are not going to sell for long.

Bringing in an audiophile component into your system will likely give it a big boost. My rule of thumb is you need to jump at least 2x in investment to get a clear and substantial improvement. So, I think the Gyphon meets that criteria.


However, you are talking about a system. While you can absolutely make good speakers sound great by investing more in electronics. In the end, you have a system and to have it perform well you need all equal performing carefully chosen components .


My rule of thumb in investment is 35% speakers, 15% streamer, 15% DAC, 20% preamp, and 15% amp. It is not a hard and fast rule. But I have gone through half a dozen upgrades over the last fifty years and usually ended up about there. My current system is $32K, $22K, $17K, $17K, $22K respectively… as an example.

Those of us that are really passionate about this tend to plan our upgrades to a new level, although it may take several years to get there.


I hope this is helpful.


Second sentence, "And no, I’m not presently interested in separating components that much further (e.g. separate DAC; separate amp; clock; etc. etc)."


Very first reply, "Have you considered an outboard DAC?"


Do people not read or just figure they’re going to disregard what’s been asked or already stated? Baffling.

Gryphon by miles

Agreed. @gill_benedek , if you can  get a used Gryphon within your budget, throw the Hegel and NAD in a ditch (it's a no brainer).

The gryphon does a bit better quality parts in general  they make some very expensive gear.

NAD M33 did not last more than a month in my system.  I was not impressed with it.

your hegel 190 is 150w, which is more than the gryphon--unless you're planning on powering inefficient planars in a very large room, i'm not sure you need more power, though i certainly understand the urge to change/upgrade. i would think you'd get more bang by upgrading your speakers. happy hunting in any event.

Have you considered Bel Canto? The E1X integrated is what I’m looking at right now to simplify things. I’ve got the DAC 2.8 and if the DAC in the E1X is as good as the 2.8 then this should tick all the boxes.


I have the Hegel H390 and really like it as an integrated amp although now that Hegel is heavily discounted the H590 because of the H600 release, I don’t think you can really do better for for the money. They are both neutral to a tij warm sounding.

All the best.

h590 is sonically vastly superior than the nad (leaving aside the nad’s ability to do dirac, which may benefit some room applications) - top hegel is one of the very best, purest sounding amps out there, regardless of price

can’t speak to how to compares to the small gryphon

I’ve had 3 Gryphon amps.  There’s no contest here assuming the Gryphon is in good condition.

There is Gryphon Diablo 120 from Canada on US Audiomart for about $7k, US dollars, plus shipping. I decided not to get it so it's yours if that's what you wish.

Forget Nad. Hegel I know nothing about.

Diablo, hands down. If you can wait a little, there should be some good deals on the Diablo 300 since its replacement is coming. I was in awe as to what the 300 can do, especially in the bass region. I think it is a much better performer than the 120. 

Diablo 300 > Hegel 590 > Diablo 120

NAD doesn't belong in that list, sorry!

If possible audition the Gryphon and the Krell.

The Diablo 120 will work nicely with your speakers.

I had the Krell driving Wilson Sabrina's (excellent ) 

Different sound than the Hegel 

I suspect that those dismissing the $12K H590 against the Diablo have never heard the Hegel or are unfamiliar with the brand! Gryphon’s cheapest Amp is not going to be significantly better than Hegel’s best Integrated. Maybe the Diablo 300 would be a more direct competitor. Do not assume that just because it says Gryphon that it’s their best effort especially in the $6-15K region! 

If the Gryphon doubles at 4 ohm and 2 ohm I would not be concerned.  I see it puts out 440W @ 2 ohms.The big Gryphon will drive anything.  I have not seen a class D products that do that.  I don't listen to lots of gear but heavy and doubling Watts are critical to me.

Hi All: What a rich response thread!  For those keeping track, here is the top-line: NAD cannot hang with Hegel and The Gryphon.  And I have moved on accordingly.

Hegel 590: about 7 votes

Gryphon Diablo 120: about 6 votes

Negative votes for NAD

I am planning to move forward with Hegel 590 (contingent on certain pricing), and look forward to having a true A/B test--my system with a 190 versus my system with a 590.  

I got the H590 to drive my Harbeths because Harbeth demos their speakers at shows with Hegel amps. And I did find it drives them better than my other amps, which includes the ARC Reference 150SE. So… at least with Harbeths it’s the amp to have. I think you will be pleased with it.

Hello gill_benedek!  In my experience, the "room correcting" feature of many companies makes an enormous improvement in my systems. I have five systems in the house (and a very tolerant wife), all have been "corrected." NAD uses the Purifi Audio output sections, which are are very good (I have four of them - two stareo pairs). Surely, the NAD is worth a try. Haappy listening!

You don't always get what you pay for. Boutique audio is the proof of that. 

But, If you don't pay for it, you won't get it!   Good power is unfortunately not cheap.   

The Hegel is out of my price range, so I just ordered a Vidar to get "decent". Not sure if it will actually be an upgrade to my own amp.  If I had gone class D, it would have been a Buckeye. 

@tvrgeek I'm not sure what your budget would be but the H590 can be had slightly used at very good prices.  As an example:

I purchased the H590 from an original owner a few years back.  You would never have known it wasn't brand new when I received it.  As quality amps are built to last for decades, paying 50% or more extra just to get the "new car smell" has always made me ask why.  Cheers. 


I purchased the H590 from an original owner a few years back.  You would never have known it wasn’t brand new when I received it.  As quality amps are built to last for decades, paying 50% or more extra just to get the "new car smell" has always made me ask why.

I wonder if there are any purchases other than high end audio equipment that suffers such a loss in value over a couple of years?  It's worse than purchasing a car.

Many years ago when I lived in Boulder, on Pearl street was a huge used store. Most stuff was buy @ 25%, sell @ 50.   Got a lot of stuff there.  Some special stuff held it's price better. Luxman and Mac amps, Revox reel to reels.  

Just about all stereo stuff has progressed in the last few years in quality and price.  So be careful looking backwards through rose collared glasses.   Also be aware that some equipment does age. Big electrolytics dry out and their ESR skyrockets. Pots and switches get dirty.   Also be aware, about half of what one finds on E-bay has hidden defects. 

It is worth respecting what running a brick and morter costs.  If they can't make 50%, they can't keep the doors open. Middlemen not much better.  That is why a lot of companies have gone direct sales. Thy take the middlemen cut, but save you the retail cut.  IF you know what you want, win-win.  Of course, some hold direct sales at the same price as their retail outlets to protect them.  Otherwise it is like cars. You go to your local high-overhead dealer and cost them time test driving, then go online and buy from a volume seller. 

I had a max for the amp of about 3K, but did not have to spend that. I am hoping the $700 for the Schitt is a safe move.  If not, there are quite a few others. Atoll, Hegel, Denafritps, Anthem, ATI, Acrus, Aragon, Audiolab, Rotel, Outlaw, Soncoz and that is not touching the class D.  ...  


Wow - I’ve had the H590 for 2 years and haven’t touched all of its many features and capabilities mentioned in the review - I wasn’t even aware of them all.

As I noted, I got it because it was one of the best driving Harbeths.

word to the wise -- savvy buyers would snap up well-cared-for, used h590... now that hegel has introduced the h600

improvements are in the dac section, the amp section is the same (bent holter’s revised thinking on amp design was installed in the h590 when it was introduced, and now carried forth into the 600 without material change)

at the prices that h590’s are trading at, one can obtain truly ’highest tier’ quality of solid state amplification for a silly low price (as such things go... in the sphere megabuck/nosebleed amps like d’agostino, boulder, dartzeel, gryphon et al)...

I think everyone steering you away from the NAD is good advice. Not a bad amp but not in the same class. 

People seem generally happy with Hegel so it seems like a solid choice. I haven't done direct comparisons, but Gryphon will give you a very different sound quality. Not necessarily better, but different. As a manufacturer it is in a very different class from Hegel, and if such things matters to you, it is still handmade in Denmark (vs. having a lot of Chinese-sourced components like most other manufacturers, including Hegel). Personally I have found Hegels rather plain-sounding and not particularly engaging. Different Gryphon models vary in character, and I have not heard the 120, but I understand it is the most "warm and cozy" model in the lineup. One thing all Gryphons have is an incredible solidity and dimensionality to their midrange and bass - not tube-like, but with a comparable density of tone and none of the thinness or grain of most solid state. Somewhat like Pass Labs, but with even more depth. Hegel is good, but still sounds more akin to typical SS to me.  

My journey started as a vintage/listening to vinyl rig and I’ve slowly been updating as my usage/wants have changed. I started with a completely restored Yamaha CT-810/CA-810 amplifier streaming music from a Node n130 through a Denefrips DAC. My vinyl source was a Music Hall 9.3 with a MC cart with a Vincent PHO-701 phono amp. I decided to try to upgrade the amplifier and possibly simplify my setup with the NAD M33 as an all in one. I started streaming some high res music and I was disappointed with the NAD. It truly didn’t sound nearly as good as my vintage Yamaha integrated amplifier. I thought maybe the Denefrips DAC was making the difference but even plumbing the node directly into my old Yamaha it was still way better. I then went to the Hegel 390 and this was clearly better than the NAD for my ears anyway. Funny thing is that in the end both the Hegel and NAD were returned and I ended up with another Yamaha. An A-S2200 now holds down my shelf.🤷🏻‍♂️


This was a long way to go to say I didn’t like the NAD right from the start.

@marcyun I met Rune Skov of Gryphon at a demo, he said that all Gryphon amps are very neutral, except for the Antileon and Diablo 120 which are warmer, rounder and a bit colored.

@bigtwin how much of a difference did going from the H590 to H30 make exactly? I see that you have them monoblock configuration in your picture?

I had H590 and downsized to H390, did not see a big difference in my space. The same formidable detailed sound. I would change your speakers though. I had great resutlts with Dynaudio and Stirling (Harbeth like). 

I’ve had the opportunity to audition all three of the great integrated amps that you’re considering, extensively, and here’s my assessment (I auditioned the Gryphon Diablo 300). The NAD M33 is great for the money, but system matching is critical with it. The NAD M33 isn’t in the same league as the other two. The Gryphon Diablo 300 outshines the Hegel H590 when it comes to build quality (although the Hegel H590’s build quality is outstanding as well), and aesthetics. But, that’s about as far as it goes. Firstly: The Hegel H590 should be compared to the Gryphon Diablo 300, along with all other best-in-class reference integrated amps currently on the market.  When comparing the Hegel H590 to the Gryphon Diablo 300, honestly, I could go either way. I use an outboard DAC, so I’m referring to the sound quality of the amp/preamp sections of each integrated, exclusively.  To my ears, the Hegel H590's awesome sound quality didn’t have to take a back-seat to any other high end integrated on the market, including the renowned Gryphon Diablo 300 (the Hegel H590 is pretty "renowned," too). I strongly believe that the H590 is a much better value than the Gryphon Diablo 300, as it’s very comparable to it in terms of sound quality (and I do mean "Comparable"). I’m not one of our more well-heeled audiophiles.  High end audio is expensive enough as it is. I definitely don’t have money to burn.  So, for my money, I'd undoubtedly go for the Hegel H590, save a bundle of dough, and just forget about the rest.  The Gryphon Diablo 300 is one of the best, but so is the Hegel H590 (for less). To be totally candid with you, I auditioned several other integrated amps as well, including the above mentioned, and I has prepared to spend more money for something like the Gryphon.  But, I was so blown away by the Hegel H590, I purchased it and never looked back.  Kudos to Hegel Music Systems for producing such an absolutely fabulous product.

Auditioned many integrateds including the 3 the OP is asking about, bought the 300, to my ears the best of the lot.

Here is my informal ranking of the integrateds:

Gryphon 300

Accuphase E-5000

Aesthetix Mimas

Mcintosh MA12000

Hegel 590 <-> Gryphon 120

Luxman 509


My system:

B&W 804 D4s

Lumin P1 streamer/DAC

Lampizator Baltic V4 DAC

Linn LP12 Selekt TT

Primaluna EVO 100 phono stage

Transparent and Audioquest cabling

Puritan power conditioner and ground system

The Accuphase I suspect for most ears is as good as the Gryphon, just not to my ears for my musical tastes which run the gamut from ambient electronica to jazz to chamber music to classic rock etc. Those with less broad musical tastes - vocals and acoustic instruments for example - might even prefer the Accuphase for its more refined tone/timbre. The gap between the 300 and the Accuphase and the rest of the amps on the list is large IMHO.

Gryphon and Accuphase will last for decades. They almost never break. Listen to some people here - get one of those depending on your taste and forget about the rest. I would definitely add Boulder 866 to the list. Those three know how to do solid state amplification. Don't waist you money. Please.


Hard to compare a NAD Masters M33 to the Gryphon Diablo 120.  I consider the NAD as a convenient lifestyle swiss army knife product that really doesn't excel at anything. The amp of the NAD doesn't deliver ample current to control speakers and I find it to be severely harsh sounding at moderate volume levels.  While convenient, the NAD's built-in DAC / Streamer is average at best.  I did find the BluOS control system and the DIRAC room correction to be nice to have's but again fit into the convenience lifestyle category. 

Before purchasing my Gryphon Diablo 300 I auditioned the Diablo 120 and found it to have the same sonic footprint as the Diablo 300 with the same incredible build quality that Gryphon is famous for.  The Gryphon Diablo 120 has ample power to drive your Monitor Audio Silver 7G 500 speakers and most any future speaker upgrades you may consider. 

Don't be fooled by Hegel watts compared to Gryphon watts. Gryphon wattage ratings are always conservative and typically double down based on speaker resistance as you can see in their specs.  Hegel's specs only state wattage at 8 ohms.  Speaker resistance varies at different frequencies and rarely operate at 8 ohms.  This is the area where Gryphon excels. 

My Diablo didn't have the optional DAC module as I use a dCS Rossini as my DAC/Streamer.  I did have the Gryphon phono module which will allow you to get rid of your Schiit Mani 2 phono stage.  You'll be amazed how good a turntable can sound with a good phono stage. 

I can't comment on the Hegel 590 as I've never owned or auditioned Hegel equipment.  Based on others in this forum, it seems that a Hegel 590 would also be a great option. 

I saw someone recommend a Boulder 866.  I love Boulder and have owned many of their components.  The 866 build quality is terrific but the 866 SQ doesn't really live up to high praises I have for their separate components.  And you must use Roon with the 866 as the MConnect app that Boulder recommends as an alternative is horrible. 

There's really no comparison between the NAD and Gryphon.  The NAD feels like a plastic toy compared to the amazing build quality Gryphon provides.  The Gryphon speaker terminals are a good indication of how serious of a component the Diablo is.  And the Gryphon remote is what you'd expect from a $50,000 component.  

If you want your last integrated, I highly recommend the Gryphon Diablo 120. 


One of the few reviews on H590 which is not all that favorable. He is one of a very tiny list of reviewers I find credible. Was surprised to hear his take on the amp




@marcyun I met Rune Skov of Gryphon at a demo, he said that all Gryphon amps are very neutral, except for the Antileon and Diablo 120 which are warmer, rounder and a bit colored.

@swede58 Rune's comment aligns with my experience. If I had to characterize the ones I've heard: the Antileon is on the "fatter" side, Essence is agile and articulate, while the Diablo 300 is ballsy (but can be a little forward for some tastes). These are all very subtle traits though - I agree the entire line is centered on what most would consider neutral. I have not heard the Mephisto or Apex. :)  

@cycles2 your comments about the Boulder 866 are interesting - it was on my list of integrateds to try, but I wasn't sure how much to believe some of the raves I've seen. Boulder is probably a tad too lean for my Audiovector speakers anyway.

@marcyun Yes, he explained that the Antileon stands out from the other amps with it’s more colored sound; fuller, warmer with huge bass. He said that the Antileon will stay in their lineup forever. Rune also told us that the D120 is slightly warmer than the D300, a subtle but noticable difference.

I've heard the Gryphon 120 ,it blows compared to the 300,imo...way too many Hegel amps around for sale at any given time so those deals are kind of done with euro amps,service is questionable...for me I'd buy a Pass int 60..their customer service is surpassed by none., and the resale is fantastic 

i currently own the hegel h590 as well as the pass int60, have many hours with each into my modded maggie 1.7i’s and stock 3.7i’s

i have heard the gryphon 300 at some length driving maggies but not in my own system

when i recommend the hegel h590 to buyers wanting a higher power integrated amp, i am doing so on absolute performance and performance for $ spent (call it value)

at $12-13k the hegel competes favorably with $30k dagostino’s, $20k gryphons and so on based on performance (sound quality, ability to drive touch loads effortlessly and so on), but of course, there are sonic differences among these amps and there are ’pride of ownership’ differences too -- exclusivity, bling factor, made in xyz and so on

there is no free lunch in this world, much less in a competitive marketplace, you give up a few things to get the performance with hegel compared to more exclusive competing products -- hegel comes in a plain wrapper, assembled in china

pass is made in auburn california, has a cool meter, dag has bling aplenty, gryphon looks like a piece of industrial art, made in scandivania -- folks with money to buy any of these can choose what they want, what makes them feel good about owning a certain piece of expensive high priced stereo gear

the pass int60 has a warmer sound than the hegel, which is steadfastedly neutral and resolving (not lean, not shrill, but neutral), papa nelson adds something to the sound of his class a units... driven hard, the pass will clip earlier and show some strain earlier than the 590

my observations from actually owning these units, take from these comments what you will

at 12-13K the hegel h590 (and its replacement) is fully competitive in performance to the other names mentioned, at $6-7k used, it is a steal... performance and value wise -- you want other stuff, the others are readily available too

If you throw out the NAD, which really is not in the same category as the Hegel and Gryphon. Then you have to try to understand the seemingly contradictory comments between “they sound the same/similar” and “they are wildly different”. You are getting honest recommendations from different folks. So, one must look elsewhere to understand the difference.


My way of looking at this common problem comes from experience. I have been pursuing the high end for fifty years. As I have progressed, I have learned, both in how to listen and evaluate. The reason many folks find this pursuit so fascinating is that it is so nuanced and deep. You can learn layer after layer, for a lifetime. As your listening skills get better, your ability to appreciate and hear nuances becomes much better. Audio equipment is much like scientific instruments… the better they are, the more detail and nuance they get correct.

When you get into audiophile level gear from respectable companies you get what you pay for. Lots of the real satisfaction comes from what you don’t know when you buy it, but come to know after you own it. You learn to listen deeper and enjoy more. This is why you would buy an integrated that was twice as much. Over time you will discover nuances that you had no idea existed when you bought it.


I am reminded of a number of components I bought when I started off (used and relatively inexpensive) and suddenly became aware of a shortcoming that I had read about, for instance grainy treble. I remember a week after buying a used preamp that I thought sounded great, and suddenly (think a curtain of red dropping over my face) hearing the horrible grain in the treble… I took the unit back… loosing $250 (in 1978) in the process of trading to a used Audio Research preamp that I loved and cherished for nearly twenty years.

Great audio components teach you what is right, lessor ones show you what is wrong.


I am reminded of the Big Bang episode when Sheldon sets off to perfect scrambled eggs… after trying all sorts of variations of sizes of eggs, and ways of cooking, he concludes… there is nothing there… we do it just fine. Kind of the opposite of high end audio.




Hmmm…Sabrina, Jill or Kelly. All beautiful, all capable, but each different.  Which to choose?  Consider the entire package in each case and the correct  choice  will become more apparent.