Review: H2o Audio Signature Monoblocks


- REVIEW -

H2o Audio Signature Monoblock

Retail Price: $5,500.00 per pair

It was late July or early August and I was stuck in a hotel, on business travel while I was surfing A’gon and the other “audiophile” websites when I happened upon the Apogee user forums. There was quite a bit of buzz going on about a new startup company, H2o Audio. Henry Ho of H2o Audio had been building large class A amplifiers for many years at this point, trying to create the perfect mate to drive his Apogee Scintilla’s. Well from what I was able to garner from the Apogee website, Henry had been tweaking an amplifier using the B&O ICE module. Henry had come to a point where he felt he had created an initial stereo amp that achieves much of what he wanted. This amp went out to a few members of the Apogee users group on a trial basis. There was enough positive response to pique my interest. At this point I emailed perhaps five or six members that have had experiences with the H2o. After much email exchange and a few phone calls I had learned the modestly priced H2o stereo amp had replaced VTL 450 monoblocks, Pass Labs X600 monoblocks, and gave Reference Line Silver Signature monoblocks a run for their money. Now this was a $2,000 retail stereo amp at startup pricing. I did take this information with a grain of salt, as I am inherently a bit skeptical on new products. What intrigued me most is more than a few people replaced their tube amps with this amplifier. I have always preferred the sound of a good tube amp. In what respect you ask? In my experience tube amps almost always seemed to portray the “organic” feel and texture to instruments better. After many emails and phone calls with owners of the H2o I was intrigued enough to give Henry a call and chat a bit. I will also say I am very happy with owning Quicksilver V4 monoblocks at this time. The *only* issues where the heat produced, and perhaps not the last bit of control in the bass. With that being said, even though the H2o amps had a trial period after purchase I was not about to sell my V4’s to “experiment” with another “flavor.” Henry and I arranged a weekend in which I drove up to Richmond, VA with my First Sound Presence Deluxe Mk. II preamp and about 46 CD’s with me. (Just the necessary CD’s for demo!) I got into town quite late in the evening, expecting to go over to Henry’s house early in the morning. Now for those of you who have spoken to or met Henry, you already know he is a gentleman in every sense of the word. Henry insisted I come over that evening to get an initial impression of the system. I had listened to his system with an Adcom GFP-750 preamp (I think it was that model) as well as Henry’s Fire preamp he is building. We ended up inserting my preamp into the system in which Henry had set up with the standard H2o monoblocks. I was truly astounded. I may have made it through 8 or 10 of my necessary 46 or so “test” CD’s and I was talking to Henry about build time. I was also intent on making sure there was still the “trial period” as all the feedback I have heard, as well as his system was with Apogee speakers. I had Meadowlark Nighthawks at home… 4 Ohm load, 91 db, etc… not the same monster of a speaker to drive. The H2o also has an extremely high damping factor (1600 if I recall correctly) in which was a concern of mine. After speaking with Pat McGinty of Meadowlark Audio, he put to rest any worries about damping factor, as he said with a correctly designed speaker, the higher the damping factor, the better in general for bass control. I had been told by a couple of the H2o owners that Henry also had a “signature” model of his monoblocks that aren’t advertised… Of course I had to ask how much better they were than the standard monoblocks I was currently listening to and enraptured by. Well the reply wasn’t 5% or 10% better, but “a substantial and significant improvement” from Henry. I placed my order that evening, actually morning, as we listened well past midnight and into the morning. Thanks again for the great hospitality if you read this Henry!

About six weeks later I was placing my brand new H2o Audio Signature Monoblocks into my listening rig.

After verifying all of the cabling was correct I put Patricia Barber’s Modern Cool album in and let it play. I gave Henry a call to let him know, I am not certain these amps will work for me, they are just a bit bass heavy. Henry assured me I have the trial period to get used to it, and not to make any critical decisions until the unit has broken in. Well, it wasn’t but 30 minutes later I was calling Henry back to inform him his amps were not bass heavy. After swapping albums to Gerry Mulligan Quartet – Dragonfly and my next thought was, “where did the bass go?” and then I noticed the piano notes drifting off with subtle decay… This was the first 30 minutes or so with the new, unbroken in, H2o Signature Mono’s in home. After the second call to Henry, feeling a bit embarrassed, I promised to let the amps break in and then make a judgment. What was becoming crystal clear, even with unbroken in new amps were these amps were true to the material that was being fed through the system. Hours and days, days and weeks had passed… the treble and high frequency extension was the first to settle down during the break in process. Next after about 500 or 600 hours (in my rig) the bass seemed to stabilize, more muscular and with supreme finesse. This is not easy to put into words, however at 600 hours the midrange sounded good, perhaps even very good. However, the midrange was still ever so slightly recessed. I was considering swapping cables, and actually making some calls. I left town on a business trip and came back a few days later and the midrange had fleshed out beautifully. It was hard to comprehend that much of a change occurred this late in the game… there was about 780 hours logged at that point.

Overall, I have had the H2o Signature Monoblocks in my system for about 10 weeks now. I truly wanted to give them enough time to go through the break in process. I feel the last bit of break-in, in my system, was right around the 800 hour mark. That landmark was reached about 5 to 6 weeks ago.

I have had the intention to write a review on these amps since I brought them home. I have tried to bring myself to write a “review” of these amps at least a few times in the past couple of weeks. For those of you who know me, and others who have read a bit of my ramblings, I am usually not at a loss for words…

However, painting a sonic landscape that these amps provide has seemed evasive to me. One word keeps coming to mind… actually from the first track played when the amps were brand new, to the next track, to right now listening to background music. The word to me that best describes these monoblocks is “chameleon.” I have heard phrases in the past that “the amp just gets out of the way and lets the music through” as well as “the amp doesn’t impart its own sonic signature on the music, you only hear the music” – well both of those phrases hold true with the H2o Signature Monoblocks. However, I also feel the H2o Signature Monoblocks take it a step further… by stating I feel the amps are “chameleon” like or in character evoke a different aura in itself. Well let me state I have had amps that have “just let the music through” or have “gotten out of the way” with no signature. Those amps all DID have a signature looking back on them. One that just let the music through was very musical indeed. Anything you played upon it was musical, a poor recording, a good recording, it was all musical. I have owned amps that “got out of the way” and were transparent into the recording and the details… that again was the amplifiers perspective on the material being played.

Why I am having difficulty here describing the H2o Signature Mono’s is the fact of their “chameleon” nature. What I have determined with these amps, it IS the music, the material that you feed the system. In my opinion these amps DO allow the music to show through. You have the emotional context of the artist recorded with these amps. There are recordings that offer all of the above… those recordings we all have that you can hear a pin drop, are pristine in sonics, but almost seem rehearsed and unemotional. If that is how the material was recorded, I seem to think these amps portray that. Just the opposite is true, the dynamic shifts and subtleties, both micro and macro, occur in spades with these amps, many times within a given song. The opposite end of the spectrum is also present, if you put in say Keb Mo, where there is rhythmic drive, naturalness, musicality and also the presence. These amps will have the pace and timing and drive with the ebb and flow of the music if that is how it was recorded.

The more I write – the more I am beginning to feel this isn’t a “review” as I don’t feel worthy of putting all of the audiophile adjectives into perspective here. I will try my best to convey a bit more of my experience with this product and can leave it at that.

I can honestly say for the first time in my audiophile life I have sold a tube amp from my system. I had the remorse. In the past I would sell the solid state amp and go back to tubes… That remorse went away for the first time not having a tube amp in my system. That in itself speaks volumes to me, if not others, for I have always preferred “tube” sound over solid state. Now, there may be more “air” with some tube amps than with the H2o Signature Mono’s but other than that, in my opinion there is no drawback.

Audiophile attributes top to bottom: The treble is as accurate as I have heard on a solid state or tube amp in a home based system. I say this taking into account when the volume is played at moderate to higher levels, the best performing amps in my comparison tended to have a slight “grain” or almost “veil” in the treble crispness and clarity. With some amps, I would never have said that, until I have had these in my system.
The midrange is true to the recording. I would say it is similar to a tube amp in the regard of the overall speed and liquidity of this amp. The H2o Sig. Mono’s in my system equal or bests some great tube amp electrostatic systems I have had in the past with all of the benefits.
The bass is what is recorded. It is not only accurate but extremely well controlled and defined. Depending on what you are listening to and how it was recorded will be easily detected with these amps. No matter the volume, whether playing very low, or at quite high volumes, these monoblocks have power and control over the music to the extent it seems effortless and natural unforced as the music emanates from the speakers. Dynamics and organic texture is also apparent at low listening levels. You will not have to “goose” the volume up to a certain point to make the music come alive.

Overall I would state the H2o Signature Monoblocks are not only “chameleon” in nature to the program material being fed, they also posses the following qualities… The absolute speed and liquidity coupled with the finesse and stygian control of the woofers, all taken into account with the organic, natural portrayal of the instruments all add up to some of the best sonics I have heard in both the tube and solid state camps. There is such an effortless and natural, organic feel to the music… yet as I write this I can put in another cd and state how dynamic and well paced these amps are…

The H2o Signature Mono’s run cool to the touch, even after 33 days of constant playing during break in. They are rated at 250 wpc into 8 ohms and 500 wpc into 4 ohms. I have some photos of the H2o Signature Monoblocks under my virtual system “Sonic Oasis” here on Audiogon. The amps are approx 13” wide x 13” deep x 7” tall. The case is full aluminum (8 gauge I think – very thick) and black powder coated. The faceplate is anodized aluminum which can be ordered in silver or black. There is one solo Blue LED on the front of each amp when power is on. There is a removable IEC for the power cord. The Sig. Mono’s have dual sets of binding posts on the rear of the amp, as well as both single ended and balanced inputs which can be switched externally with a toggle switch. Each monoblock is approx 50 lbs. or so.

Again, this review mirrors my experiences, in my system, and is based upon my opinions. I hope this helps shed some light onto this new startup company’s product. The website is:

www.iceh2oaudio.com

The website is under construction so don’t expect much. I am not sure if Henry has a dedicated phone line as of yet, if you wish to contact him there is email contact on the website, or shoot me an email and I can give you his number. I am in no way affiliated with H2o Audio. I am an extremely satisfied customer – both with the product and how Henry runs his company. At the time I ordered, there was a two week trial/satisfaction period after purchase. Anyone in the market for an amp in this price range would be doing themselves an injustice not to look into this amp, in my humble opinion. Soon there should be reviews coming out in 6moons as well as another I am not certain of.

Amplifiers I have owned in the past include (but not limited to… in case I leave one or two out): Bryston 4B, McCormack DNA-1 Deluxe, Music Reference RM-9, Sonic Frontiers SFS-80, Cary SLM-100 monoblocks, McCormack DNA-2 Deluxe, Quicksilver V4 monoblocks. I know there are others I am leaving out, however these are the amps that have had extended stays in my systems.

Associated Equipment:

Meadowlark Audio Nighthawk speakers
Synergistic Research X2 Resolution Reference FX biwire speaker cable
Electraglide Mini Khan Plus power cords on H2o Sig. Monoblocks
Synergistic Research X2 Resolution Reference interconnects (single ended)
First Sound Presence Deluxe Mk. II preamp ( NOS Siemens 7308 gold pin tubes )
Electraglide Ultra Khan II Statement power cord on First Sound Preamp
Electrocompaniet EMC-1UP CD player with spider clamp
Electraglide Mini Khan Plus power cord on Electrocompaniet CD player
Everything *except* First Sound preamp is run through BPT
BPT 3.5 Signature balanced power conditioner
Electraglide Ultra Khan II Statement power cord from BPT to wall
FIM 880 wall outlet upgrade
All components *except* H2o’s and speaker sit upon Zoethecus
Zoethecus z.5/r shelf with z.slabs under all components
Ridge Street Audio Designs cable lifts
Eighth Nerve Room Pack – wall treatment
audiofankj
Hang in there Baranyi, my Chenin will arriving soon and it will mate it with Henry's H20 Signature Monos.....The H20's in currently in my system for about a week now and I'm speechless with the way they sounded with a non-hi fi preamp...With the Chenin, I will be in heaven....More to come..:-)..I can't resist anymore......

I'm on vacation, and can't wait to go home to hear my H20's and Chenin together...:-)
Vince, good to see you on this thread (the water seems to be a bit more calm here!) What preamp are you using with your H20 monos? Hope you had a nice holiday. Bob
Just remember ICE amps like an active preamp. Choosing attending components becomes a delight for H2O owners. Preamps, for instance, will not be chosen to sooth, but to refine the final sound.
Joe,
You have even more patience than me! I am hoping to get the first pair of Scintillas back in the next two weeks. I am also planning to vertically biamp one pair of Scintillas. I have been looking into the the H-Cat preamp which is also a current thread here on Audiogon. I would like to give it a listen with Henry's amps on the Scintillas. That could be an amazing set-up. I had been thinking about the Supratek Chenin but that takes 6 months to order and receive. Anyway, I am hoping to listen to Henry's stereo amp solo before vertically biamping it. I should be receiving the first H20 within the next week. I will also play it on the Von Schweikert 4.5's that I currently use. That speaker was voiced with a amp similar to Henry's so it should be interesting as well. Bob
Bob - no change here. Tempting, but like I said, in it for the long haul. Now that I've decided to vertically biamp the Scinnies, I'm saving towards my second H2O S250. I want to break them in together - evenly. I'm now shooting for a Spring setup :)
In the meantime, the old JBL L100 Centuries don't sound too shabby through the Yammie receiver (my HT rig) - and you wondered how I could be so patient :) .
I did recently pick up an SP-10 obsidian base to anchor my future vinyl deck. I'm thinking a Dynavector DV-507 arm and a Kontrapunkt B MC ought to make for some nice analog playback through the Scinnies. The MF pre has a decent phono stage, so I should be all set. JR
Joe, Have you fired-up your H2o yet? Henry just emailed me and he is doing the final check to mine prior to sending it out. I would love to hear your impressions since our systems will be so similar. Bob
Audiofankj, did you consider Frank Dai's (Signal Cable) MagicPower cord? He has gotten great press and overwhelmingly positive feedback; pretty impressive for those of us that can't consider $2500 (or $500) power cords.....just curious.
Baranyi, the Electraglide Mini Khan Plus powercords retail for $2,500 new, however you can find them used here on A'Gon running from about $500 - $700 or so... not a subtle improvement to the amps...
I have just ordered my stereo amp from Henry and can't wait to use them on my Scintillas! I plan to buy another one in the near future to biamp the speakers. I have had a great advantage in that I was able to visit Henry this summer and hear his amp with his Scintillas. I can't wait to listen to this amp with the Scintillas and my Von Schweikert 4.5
I use the Electraglide Mini Khan Plus power cords on the H2o Sig. Mono's. I took my power cords with me to Henry's when I went to initially listen to his H2o mono's. I believe both Henry and I noticed an audible difference when the aftermarket power cords were added. Most noticably bass had more body, depth, and weight, noise floor seemed lower, and soundstage seemed to open up and become more defined. The details I just spoke of are what I heard, I can not speak for Henry as for what he felt was improved...
Rpw, Hmmm, interesting. When the first prototype H2O arrived, I found it absolutely needed an EMF rejection cord to work properly. Since then, Henry has incorporated filter devices that reject such trash. With my new amps, I couldn't hear a difference between the ferrite loaded cord, and one without. I use an ordinary cord with a ferrite clip, for assurance purposes. Of course, all amps will react differently when fitted with various cords.

Let us know what cord you settle on.

I noticed Audiofankj uses Electraglide Mini Khan Plus.
Muralman, what power cords and isolation products have you used with the H2o? I have had the S250 for about two months now and notice it is sensitive to power cord changes.
I be interested in knowing what the voltages and amperages were for the monster amp. I suspect though there may have been some other crucial and unique measurable factors as well, otherwise the 1980s designers that first developed the SS behemoths. for driving Scintillas would have designed something similar, rather than 350W monoblocks.
Henry calls his creation, "The Beast" He built it years ago. It has huge heat sinks, two farads of capacitance, and is fully class A. It provides rivers of current.
Interesting Muralman, how did Harry design an 85W amp to comfortably power his 1Ohm speakers? What is the crucial factor?
Eldartford, the H2O has been compared with various Tripath amps, including the Bel Canto Evo Gen II with capacitor upgrades. The H2O was judged cleaner, more extended, more dynamic, and deeper. As one new H2O owner has said, "The H2O is the most artifact amp I have ever listened to." He sold his Evo Gen II amps.

Stated power does not equal real guts. There are 85 watt amps that will power anything. Henry Ho, the creator of the H2O, built such an amp for his 1 ohm speakeers. The trick is in how the amp delivers power.
Muralman, you used to have Oddyssey Monos Right?
What happen ? Did you sell them?
Muralman1...Yes, CarverPro uses the Tripath module. The Tripath people will tell you why their design is better, and the ICE folk will blow their horn. The only thing I know for sure is that the H2o costs more than three times as much and delivers slightly less power. And the CarverPro comes with 5 year warranty.

The ZR1600 is one damn good amp, and I am sure the H2o is also. I would be interested to see how the H2o compares, and, if it is better, is the difference worth two grand per channel (and I have six channels).
I believe the Carver is a Tripath based amp, no? the H2O does not cost four times as much for nothing. Looking at the innards of the Carver, it reminds me of the PS Audio. The H2O chasis is packed tightly with power caps, and a 1kw transformer. No Tripath amp has been chosen over the H2O as yet. Who knows, just maybe, the Carver......
I might buy the stereo version, partly out of curiosity regarding how it might compare with my CarverPro ZR1600. The comment about the H2o resembles what was going around several years ago about the ZR1600. The main difference is that the H2O costs three times as much. Of course the ZR1600 includes a bunch of extra features for pro sound use, and these are bypassed in the home audio application, but I'm sure they add to the cost.
Sorry for getting defensive. Henry never joins in to defend, or explain, his amps. Being his friend, I wade in, sometimes stumbling.

I think Strajan, perhaps, was writing defensively. The "cave" is awkward. I am curious what wires shorted. It wouldn't have been the light wire.

By the way, Oxia, you were a major influence on my decision to try the ICE module eAR amp. I still had it, when I got my first H2O, an early prototype. All who listened gave the H2O the nod without hesitation. The production model S250 H2O is even better than it's predecessor. The Signature, reviewed above, is in a class of it's own, IMHO.
Muralman,

FYI, my post was meant to address the concern expressed by Loudandclear. To me, the issue isn't whether a person has "sense" or not. It's simply a matter of accepting the fact that accidents do happen, and it's up to the buyer to decide whether he or she values a design that is "bullet-proof". Having said that, I do think that Srajan laid it on a bit thick in the 6moons review regarding the supposed "design flaw" of not having short protection circuitry. If this is a flaw, then probably upwards of 80% of high-end amps are likewise flawed, yet I don't see Srajan applying the same standard to other amps that he's reviewed. I'd wager that he would not get many review samples if he pulled that stunt more often.
I would expect anyone with any sense not to cross wires of any amp. It has always been known such an act invites blown speakers, if not the amp. I would never choose an amp based on it's "fool proof" design. The Acoustic Reality amps have incorporated in them a trip wire, that breaks when the cover is removed. I know, because I had to replace an internal fuse twice. One can remove the cover of the H2O without concern. Also, the H2O has easily accessible connectors that are fully visible.
To be fair, the 6moons review of the Acoustic Reality amp reported that the reviewer caused the short circuit after he had opened the amp and accidentally severed a wire. I don't know of many amps that would invite such damage to its internal wiring and emerge unscathed.

To my knowledge, only the ASP and ASC series ice power modules, which feature an integrated switching power supply, has built-in short circuit protection. However, the general consensus seems to be that the A-series icepower module (which is the version used in the Rowland 300 series, the eAR amps and the H2O) sounds better. The A-series requires an ancillary linear power supply and has no integrated short circuit protection, so the amp designer must add it himself. I could be wrong on this, but it appears that today only Acoustic Reality has an A-series icepower amp with proprietary short circuit protection.
You need to be careful with some of the IcePower modules because short circuiting the speaker terminals will bake the module. See the sixmoons.com review of the Acoustic Reality ICE amp.

Otherwise, you should be fine as the amps run cool.

H20Audio is a new company, so a bit of concern there, but Henry is a real stand up guy who stands behind his product.
Can anyone comment on the projected reliability of these amps or if anyone has encountered any problems in performance?
I've read that the ICE module is a very good package, and some other designers are also using it. Your review is further assurance that the ICE module is all it's "cracked up" to be.

The designers(B&O) have always been basically a "mid-fi" company with most of their stuff, but apparently they really hit on a high-end design with the ICE module.
Guidocorona, yes I would direct your questions to Henry. I am runnning all single ended as Emmanuel Go of First Sound (my preamp) designs his preamps for single ended use only.

Kclone, I would speak with Henry on the specs of your preamp, unless there is a red flag of input/output impedance mismatch, I would agree with you that this is really a "can't miss" purchase... especially with the "trial" period after the purchase... just keep in mind breakin does occur over quite a bit of time...
Kclone, yes, the H2O is mortal after all. If anything, it's frank honesty in reproducing what is feeding it will only exacerbate anything not right before in the chain. Unlike amps that bear hard with crayons, there will be no masking available.

Therefor, I keep my H2O system simple.
This seemed like a can't go wrong or can't miss type of audio purchase. Then you said it is very important the rest of the system is a match for it. Therefore, it is not unique in that regard.
I think I mentioned it in the review... one preamp Henry had on hand was the Adcom GFP-750, the other preamp was his "Fire" preamp.
Great review, Audiofankj. What were the other two preamps? One was an Adcom 750, I believe.
Audiofankj, I notice you are running single ended, but H2O has both RCA and XLR inputs. Wouldn't it be beneficial to run these amps on a fully balanced system? Is the design fully balanced with simmetric/double circuitry, or is the balanced design achieved with phase splitting, or other means? Perhaps these are questions that Henry may be able to address on this thread. Guido
Thanks for the input... I actually posted this in the wrong area, so I reposted it in the Review section... I also stated, "After reading what I wrote above it seems apparent to me that I did not convey just how pleased I am with these amps. I still am a bit frustrated by not knowing exactly how to put the performance into words that do it justice. I think that fact in itself left my "review" a bit cold sounding. I want to express that I am very pleased with the performance of the H2o Signature Monoblocks. They continue to astound me and gain my admiration. I would also add if you are considering a new amp I would highly recommend considering these. All of the glowing press that drew my attention to this company was mainly based upon their $2,500 stereo unit. I feel the H2o Signature Monoblocks will be a "staple" of my system for many years to come! " - this was posted in the review area...

Yes, this amp although it is ICE based technology (some type of switching, I believe) runs in the analog domain and is coupled to an analog power supply, thus it is *not* a digital amp. It does portray an analog like sound, however it also posseses the liquidity and speed that don't always accompany many of the analog sounding amps... Henry would be happy to speak with anyone about the technological side, however much of it was over my head.

I personally felt the First Sound preamp mated with the H2o's were better sounding than the other two preamps. With that being said, I am biased, and unfortunately I "hogged" the sweet spot listening while up there and Henry was not able to fairly make a better/worse than comparison with his other preamps. I felt the First Sound improved upon dynamics, both micro and macro... the depth and control of the bass was astounding. Overall liquidity, timbre, "organicness", and soundstage were also bettered with the First Sound in my opinion. Hope that is of some help, Baranyi.
Good Review!

I also found Henry's amps quite musical - almost "analog" like. Very effortless. They do need decent partners though.
The speaker has to match. The preamp is also key, as the input impedence on the H20 amps is on the lower end of the scale (driven by the IcePower module).

Congratulations on you success . . .
Thank you for your fine review. I am planning to purchase an H20 amp from Henry and your review helped confirm my own point of view about these fine amps. I am rebuilding Apogee Scintillas so this amp is really a no brainer. I was wondering how different sounding was Henry's system when you inserted your First Sound preamp in his system. I had the pleasure of visiting Henry this summer with my family. It was shocking to me hearing the 20 year old Apogee Scintilla sounding as realistic as any speaker that I ever heard. Listening to this system felt like we were at the actual event of making music. Bob