Tube Pre/ Class D Amp - Who has done it?

I have had a pair of ADG Class D monoblocks in my system. My preamp is an Audio Research Reference 6SE. I was really impressed at the  sound for the money. 

One thing, I will say, that when you take out one piece of equipment with a very synergistic system... that one piece tends to sound as good as it ever could. So I had all Audio Research electronics a substituted just the amp. 

But sounded great for the ~$9K

I had ARC sp16 and Bel Canto ref1000m monoblocks for many happy years. Moved on to newer Class D and dropped the tubes.

It was a very”musical” combo I could listen to for hours, but slightly rolled off high and low end extension, and slightly limited dynamics air and detail.

I recently bought a Marantz PM10 for my summer home, but had it shipped to me at my Florida home first to check it out.  The PM10 was used in lieu of my Conrad-Johnson ART 27A which is Class A, and I used my C-J ART 88 as the line stage.  My speakers in the system are Sony SS-AR2, which have a rated efficiency of 89 db at 1 meter and are a fairly easy load.  So the PM10 was not driven very hard, but in terms of sound quality it acquitted itself very well.  The PM10 line preamp section did not compare as well and so I did not bother to compare the phono stages.  The ART Phono is one of the great phono stages.  When I took the PM10 up to it's permanent home and connected it to B&W 802 Diamonds it worked much harder, but also sounded quite good.  This has been my first experience with Class D amps outside of subs and it has been very satisfactory.  A good tube pre connected to a Class D power amp can be a winning combination. 

I have a system with a tube preamp (ProJect Pre Box RS2, selectable tube stage) and a Class D Purifi amp (NAD 298). It is a very good combination.

Macintosh 12000 tube/ ss pre hybrid,either ss or tube.mcintosh class d mi1502 500 watt/ 1000 hypex class d with good synergism.enjoy the music.

I have an Atma-Sphere MP-3.3 tube preamp pushing Atma-Sphere Class D mono blocks and they're glorious. All the beauty of my previous Atma-Shpere M-60 amps without the 12 tube-per-monoblock paranoia. Speakers are Zu Druid Vs, not hard to drive at all but loving the headroom provided by 50 watts.

I have a Schiit Freya+ preamp with 6SN7 tubes feeding a PS Audio S300 class D amp into Harbeth 30.2 XD Speakers and a REL T/5x Sub. I like it.

I use an Aric Audio Super 6sn7 linestage with an Orchard Audio Starkrimson Ultra. 

I have used two hybrid integrated amplifiers in my second system:

1. Rogue Sphinx v3
2. Heaven 11 Billie v2 (current)

Speakers have been:  Zu Omen Monitors; Golden Ear BRX (current)

Sources are:  PS Audio SACD Transport; PS Audio Perfect Wave DAC; Technics SL 1500c TT.  

I like the system, don't quite love it.  It sounds very good and is perfectly fine, it just doesn't move me the way my main system does, which doesn't have components that are that much better.  

I know speaker set-up is part of the issue (on top of 5 foot high bookshelves).  I think the answer is an all tube amp, though I have been very distracted the last year or so.

Rich 

My Luxman CL-38uC preamp and my Red Dragon 500 mono-blocks sound wonderful together.

I have a BHK preamp controlling my Atma-Sphere Class D amps I am amazed how good the combination sounds. I also have. a pair of Cary 211FE amps that I also use with the same preamp. It is nice to be able to go from an all tube system to a hybrid with the Class D. 

I have a Cary SLP-05 tube preamp and used a well known high quality 500 watt GaN class D amp for a while.  

The sound was comparable to the better Class D amps I have heard except truly the speed of this amp was off the charts.  It was able to delineate differences in rapid fire percussion like no other amp I have owned or heard.  Actually topped the speed of the Pass XA25, another unusually rapid fire amplifier.  

I just did not prefer the overall sound of the amp.  Somewhat drier, matter of fact, not even a hint of glow.  

I would recommend a quality class D amp if you need lots of relatively economic power for current hungry speakers like Magnepan or have a need for amplifiers with a light weight compact footprint.  

Based strictly on sound quality the answer is no.  

Due to a recent change in speakers, I decided I needed a more powerful set of monoblock amps than my Herron M2 class A/B amps (160 watts each) which were matched with a Herron VTSP-360 tube preamp.

I decided to give the PS Audio M1200 Stellar monoblocks a try. They are Class D, and 600 watts each. They have a single tube in the input stage.

This turned out to be a nice pairing, providing the power needed for my power hungry Gershman Studio xDB speakers while giving up nothing in sound quality to the Herron amps, which sound amazing, but just didn’t have enough grunt for the Gershmans.

I also have an older Wyred 4 Sound stereo amp in a second system paired with an ARC LS26 and Klipsch Quartet speakers. The W4S amp is just a little rolled off in the treble, which results in better control of the "shouty" nature of the Klipsch speakers. It’s in a bedroom system and not set up ideally or ever played very loud, but sounds great at moderate volumes. It could be a nice main system for someone on a budget.

I use Atma-Sphere Class D amps during the summer with an Atma-Sphere tube preamp.  It’s a very nice combination as you might expect.  I still prefer the Atma-Sphere tube amp during the remainder of the year unlike some who have reported here in the past, including its maker.  Like everything else in this hobby synergy is the key.

I have a Shindo preamp into Quicksilver V4 monos(170w into 8 & 4 ohms w/kt150s). Went to a difficult stand speaker, 85 dB, 4 ohm dipping down to 3.2, ouch!  Tried class D power amps because of the drip in impedance, base got faster but everything else, (ie, what I call tube magic) was lost. 
 

Class D has its place in my opinion, just not in a critical listening environment when the life of the music is most important.  

@daytrader bass got faster but everything else, (ie, what I call tube magic) was lost. Class D has its place in my opinion, just not in a critical listening environment when the life of the music is most important.  

+1, yep, and the difference is notable when comparing to good tube amplifier designs and tubes. Getting closer but not there yet [in most cases]. A few designers claim to be as good as or better now with Class-D, and hope they keep working at it. Will be interesting to see more Class-D powering all parts of the main speakers [not just low freq] showing up at the shows next few years, as tbd.  

dehavilland 6SN7 style preamp into hypex amp. Very nice combo but still a bit sterile in mids and bright/forward in highs.

By way of usual audiophile nonsense, I once had my VAC Master tube preamp ($30K) hooked up to a NAD M22 (nCore class D). It sounded great! Much MUCH better than with matching M12 digital preamp, which was comparatively awful. I even considered sticking with this combo for a while (in my second system), or upgrading to the M23 (Eigentakt). However, in the end - yes, I still prefer either a really good SS class AB (Phison) or tube amp (VAC), versus the class D. But that little NAD M22 was a hell of pleasant surprise, and it’s super for the money (my other amps are much more expensive). However, I think it really benefits from a tube pre to round out its sound for best 2ch enjoyment. Yes, it is "drier" in comparison to really good traditional amps. 

For few years i used Primaluna Prologue Premium preamp with Nord Hypex NC500 class-D poweramp. Was quite happy with the result (Focal Electra speakers). When tested RME ADI 2 DAC with integrated preamp instead of Primaluna, sound was clean, but lifeless, unnatural and boring, in lack of better description. Later switched to Primaluna EVO 400 preamp with much lower output impendence, and that had better extension and clarity, very obvious improvements after few seconds of listening!  

I've done it with a Voyager GAN 300 wpc class D amp with an Aric Audio Motherlode II tube preamp.  Now am running the combo of a PSAudio M1200 class D hybrid monoblocks driven by the Aric Audio Motherlode XL tube preamp.  The latter combination is the heart of my reference system and, for the record, it sounds heavenly.  I have had awesome solid state amps - the JC1 Prarsound monoblock amps for example - but I don't miss the sonics of those backbreaking boat anchors because of the outstanding Audio reproduction of my reference systems.

I’m have a Raven tube preamp from Spatial Audio with a D-Sonic m3a-1200-s amp driving Gunned MMGs.

I use a Italian Lector ZOE preamp, with a CI audio class D amp with excellent results. The ZOE got a major major upgrade when I installed NOS brimar tubes, totally transformed it, the ciaudio is stock except for a excellent Synergistic Research fuse...

Really love having a small light amp that doesn't run hot, and sounds as good or better than my old Sonic Frontiers tube amp that had eight KT 88s, weighed 160lbs, and could heat your house.

Had a PS Audio BHK preamp and M700’s for a couple of years. They worked well together, but I still thought the same system sounded better when I replaced the M700’s with a CODA continuum 8 class A/B.  But really, I don’t think you can generalize about whole classes of amps. Maybe the Atmasphere class D amps would have been as good or better than the CODA.

I normally bi amp with a VTL ST 150 and a Nord Audio Purifi Class D driven by a VTL 5.5 pre but the VTL pre is currently in for repair. So I am now using the Class D full range and the SQ is very good, maybe not as 3 dimensional as when bi amping with the VTL ST 150 on the mids/highs but very good anyway.

Correction it is the ST 150 that is in for repair.

Currently, as an experiment, I’ve been using a music hall 25.2 hybrid headphone amp/pre with two NAD 268 amps that are bridged (300 watts/channel). I think it sounds fantastic. It did not cost me a ton of dough, as I got deals on them. I am partial to my sugden class A and my musical fidelity class AB, but I’m telling you, this combo just works. I got the idea from the rogue sphinx which combines class D topology with tubed pre section. I think they are/were on to something. What prompted me to do this was I did not think my other amps provided the oomph I needed when I wanted to rock out with say AC/DC, zeppelin, etc. I can tell you that I’m no longer wanting for that oomph or volume with the aforementioned combo, bizarre as it may be. The MH 25.2 is a hidden gem of a component when used as the pre. My next test is to sub in my passive pre, combined with the NAD"s. For class D, the NAD 268, to me, sounds warm and detailed with no grating harshness. I was surprised, and it has changed my mind about class D. I use the Tannoy eatons biwired. They are fairly sensitive and also add some warmth to the sound, which I’m sure the MH 25.2 is also adding with its tubes. I’m also using, with the NAD’s, the music hall A3 tubed phone stage, equipped with a volume control. That too sounds great. ASR reviewed the NAD 268, and gave it a very favorable review. Other than that, not much fanfare from other reviewers. Some here may look upon these components as total sh#t, I don’t care, I took a gamble on them and I’m loving it. So Tonight That I Might See by Mazzy Star has never sounded so good! Totally enveloped by the music.

Class d is comming of age the fosi audio monoblock is a bargain you can change the op amp to what you want sound wise.i do like d sonic,who doesn't like 2 kw into 4 ohms Dennis is fun to talk to.enjoy the music

Really happy to see all the on-topic replies here. Especially happy that this discussion has stayed focused on the union of tube and Class D as opposed to a free-for-all discussion about Class D vs whatever you like better.

Those discussions are already plentiful in A’gon.

I ask this question in part because I'm about to go fully active in my main system and wanted to know what kinds of combinations had great synergy, but  also because I've always suspected that a juicy tube pre with a solid performing Class D would be heavenly.

I used to run Orchard Audio Ultra DMC Stereo & Monoblocks with a BAT VK50-SE for many years. But recently, I've moved onto the Black Ice Aries/DAC/Preamp driving the Ultra's. Sometimes I'll direct drive the Ultras with my PS Audio DirectStream DAC Sr. (MK1). It's fun when you have options.

The Orchard Amps are a "straight wire with gain" philosophy which will then tell you how good or bad your source is. 

Gato dia 400s.

@erik_squires What amp or amps are you getting?

I run an Allnic L-7000 pre with Atma Class D’s and don’t miss the heat, but @marco1 has me curious to see if I need to test the Atma tubed power amps to see if I missed something.

I use an Audio Research ls28se Pre, in the past I used PSA m700 monos then switched to M1200. The M1200 really thump out the bass and that is what I was looking for as my speakers hold 4 12" woofers each. I have them and my subs running tru a modified mini DSP. Bass is very tight and controlled. 

I’ve tried Primaluna, Zesto, PS Audio BHK Pre (Hybrid Tube) with SS amps, class D included.  If you get the gain matched correctly, works really well, blending some of the tube magic with some of the attributes of SS / Class D.  Exciting to watch Class D technology, design continue to evolve.  Most of the designs in Audio currently are mature, tweaks that can be made but not the leaps happening with Class D.  Class D designers are working overtime to dispel the old stereotypes associated.
 

I'm running an ARC LS25 Mk2 pre with a DS225 amp.  It's not reboxed modules, it's ARC's class D design and sounds very tubelike.  I leave the amp on 24/7 and it only draws about 10-15w while idling.

I have been looking at doing a similar combination with Orchard and a Rumba Extreme.  

@erik_squires What amp or amps are you getting?

@lwin - I'm getting 3 way plate amps made by Hypex.  I'll be removing the passive crossovers and re-working them with the built in DSP capabilities.  It's not a straight conversion.  In addition to a white-paper redesign of the crossover I'm adding 2x 10" subwoofers to each speaker.

I've been using my LS7 tubed pre with a Classe D two channel amp for years and I genuinely love the combination. I've tried a couple of beefy A/B amps but the Classe seems to sound better at moderate volume, which is where most of my listening is done. When I do want to crank it up, no problems there either.

Sorry ARC preamp (ancient) in case anyone is wondering.

I have been using various combinations of tube pre / Class D amps over the last 7 or so years. Rogue RP-7 (really nice for the cost), ARC Ref 6SE (hard/aggressive), currently Backert Labs Rhythm now upgraded to v1.4. Amps - LSA Voyager GAN 300 (just OK), Bel Canto Ref1000 monos (rolled off HF), currently AGD Tempo upgraded to the current version. The shimmer, finesse, and depth of detail and imaging of the Maggie/AGD/Rhythm without any sharpness is quite addictive.  

I got a pair of LRS+ a few months ago (yes, I use a sub) and while the AGD drives them pretty well I thought I would try a higher powered amp because of their inefficiency. So I tried a pair of Orchard Starkrimson Ultra Premium LPS mono blocks. They definitely had the juice to drive them but I didn't perceive an actual improvement in sound, so I returned them. I gotta say Leo is a great guy and was very helpful. 

So I just ordered a Bryston 3B3. Reviews say it is extremely smooth and detailed, against a black background, with significant power reserves. And supposedly has great synergy with Maggies. If it works as reviewed I will be leaving the Class D camp. If not it will be going back and I will be sticking with my AGD. 

That has been my journey in amplification over the last maybe 7 years. 

I was using an Icon Audio LA4 MKII SIG. with a Hypex Nilai for the last few months. It's pretty good for the money. I used some overly "warm" DIY preamps with other class D modules in the past that were kinda cool with certain music. 

I found the Nilai to be fine with solid state as well. I've enjoyed messing with Class D the last couple years but I'm taking a break from it. 

@j-wall if you don’t miss the heat I’m not sure that OTL’s are the way to go. Although it is nice to listen in your skivvies during the winter. In all seriousness though, I think they should match up nicely with your Allnic. Just be sure your speakers are a good match as well. Whether you’re missing anything now is something only you can answer.

My AUDIO-GD HE1 XLR 10 tube preamp with the Peachtree GAN-1 is a match that makes music sound Real..Beautiful Synergy !..Love it with Any speakers I throw at it. ...From KLH Model 3's to Borresen X-3's....I love my system .

I have been running a McIntosh C220 pre (actually a tube hybrid) with an Arion Audio S-500 class D amp for almost 6 years now.  Very happy with the synergy.  I get a touch of tube warmth (with Mullard reproduction tubes) and plenty of clean, detailed power.  No interest in any upgrades.

I ran a Rogue RP-1 with Mullards and PS Audio S-300.  Sounded great for the $s.   Ended up getting some Quad speakers so moved the S300 down the line and picked up a Quad Altera stereo A/B to try and pick up some synergy.

Bryston coming out with a new class D offering that really interests me.

I think tube pre and class D amps or A/B make a great combo.