Aesthetix IO Eclipse


I'm seriously considering this Phono preamp (with the additional line input and volume control), and would like to get in contact with potenial owners of the IO-series from Aesthetix. I believe the IO is what I'm looking for sonically (and I love the design and user experience). But, I'm slightly concerned about earlier reports of noise/hum issues, as well as riability and the practical side of things related to tube life and generated heat.


- Is the IO Eclipse (still) up there among the best on the market?
- Will the possibility of driving a poweramp directly offer any disadvantages, or be as good as or better than a separate preamp of the same caliber?
- Are the tubes worth the expense, effort and potential hassle...?

What I'm looking for is a high degree of naturalness, musicality and flow combined with great dynamics and a large, holographic soundstage.

My system:

Brinkmann Bardo + 10.5 tonearm + Pi-pickup (Analog)
Audio Aero La Fontaine (CD/DAC/Pre)
Karan KA M2000 (Monoblocks)
Sonus Faber Futura (Speakers)
Kubala Sosna Elation (Cables)

Sidekick_i, I have owned the Io Signature phono stage with dual power supplies, volume controls and additional line input since Aesthetix first made this version available to the market. It is superb, which makes me believe that the Io Eclipse is incredibly, deliciously exceptional.

Since the very earliest units, Aesthetix has had no problems with noise. Those early reports came from the resistors as provided to Aesthetix by the manufacturer and Aesthetix has long since changed to another brand and replaced under warranty the original resisters in all of those early units.

My units are 10 years old and continue in perfect condition, so I rate it very reliable.

The Io is NOT hard on tubes. I use the stock tubes in mine and find the sonics marvelous without going down the route of esoteric old stock tube experimentation. Jim White says his owners split about 50/50 in preferring the stock tubes for which the unit has been optimized (as do I) and preferred selected vintage tubes. Choose your poison on this topic and trust your ears.

Yes, with so many tubes, the Io puts off some heat. With the second power supply I have, there is even a bit more. So, be sure to keep good air flow around them and don't trap them in a closed cabinet.

Are tubes worth it? To my ears, emphatically YES! For my sonic preferences, I strongly prefer the active tube phono amplification to any solid state unit I've heard and most decidedly as compared to any transformer-based gain element.

Tube rush can be a bit of a challenge given the 82db of gain from this all-tube phono stage. This means using carefully selected low-noise gain stage tubes (which Aesthetix provides with their stock tubes).

It also means being reasonable in choosing your cartridge for a reasonable level of output. The Io will work with very low gain cartridges (down to 0.2mv), but it and you will be happier with a cartridge with a bit more output than those lowest output cartridges (e.g., 0.24 and above). I use a cartridge with a medium 0.36mv output and do not have any issues. With lower output, gain stage tube selection for low noise is critical.

I drive dual mono-block amplifiers directly with the Io and have never felt any limitation in doing so. And, I've heard from some Aesthetix owners who have carefully listened to the Io solo versus the Io in combination with the Aesthetic Callisto linestage. They report greater dynamics when coupled with the Callisto. For me, I find the Io with dual power supplies to have seemingly UNLIMITED dynamics. But, I haven't heard the alternative with the Io feeding a Callisto linestage. There are some limits to each of our resources...

How does the Io Signature compare to the Io Eclipse? I haven't yet heard the Exlipse but everything Jim White has ever described to me sonically has matched to what I also have heard. So I trust what he says are the improvements coming with the Eclipse.

If I could afford to have Aesthetix upgrade my Io Signature to the Eclipse, I would do it in a heartbeat. The changes from Io Signature to Eclipse will be the same order of magnitude or greater than the improvement from the standard Io to the Signature.

Good luck!

Thank you! That's very, very valuable.

As this will be a long term investment, it's very comforting to hear that you've been happy with the IO sign. for such a long time. Reability, support and upgrade possibilites are very important to me.

Do you have any experiences in using the line input for a digital source?

For me, the possibility of using the IO as a fully functional preamp is of major importance. Adding the Callisto (another 2-3 boxes) is not an option practically or financially.

If going for the single power supply, could you easily add a second one later, or does it require modifications to the main unit (I guess so...)?

I use the line input for a CD player. No problems at all. I will occasionally swap to a tuner on this input by switching the interconnect (I do so at the source, not at the Io). It would certainly be possible to have a source switching box precede the input to allow multiple device selection, but I don't have the need. The Io with alternate input is a purist's device, to be sure.

The only thing one might miss is that this set-up is not conducive to making recordings of one's LPs. There is no line level "Record Out" connection like one would find in a full function preamp (e.g., the Callisto). The only output is the variable output through the volume control to the amplifier. For me, this has been the only limitation and I'm pleased to accept that.

Since I listen principally to vinyl, and since adding a Callisto was not a financially practical option for me either, the Io with volume controls and high level input has been a perfect choice for me. It has given me one of the best phono stages available to optimize listening to my preferred source (vinyl), but doesn't restrict me from listening to a digital or other source when I choose.

The second power supply can be added later. There is a modification that has to be made both inside the head unit and inside the original power supply, but it is not major surgery. Glenn (Aesthetix's pre-eminent technician and master of customer support) has been known to step a good technician through making the change, or send the Io to the factory and they will make the changes, check out the unit and ship it back with the second power supply.
By the way, when I was debating about the second power supply, the following it what Jim White told me *he* hears with the addition:
Adding the second supply improves the sound in the following ways:

.. Added space
.. Improved macro dynamics
.. Improved micro dynamics
.. Blacker backround
.. Greater ease to the sound, less strained
While this comment related to the Io Signature, I would expect it to hold true for the Io Eclipse as well.
If one chooses the "Io with high level input" option, what is the signal path after the high level input jack on the Io? Is there an actual linestage section built in, or is it just passive? If the latter, then one must consider amplifier input sensitivity (does the CDP or other high level source output enough V to drive the amps, or does it require the added gain of a line stage?) and length of interconnects (if the Io is passive with high level inputs, then one should think about capacitance of the cables and input impedance of the amplifiers as factors that could affect frequency response).

Do you guys know what is the role of the 2nd PS chassis, if one chooses to acquire it? I mean to ask what part of the Io audio circuit is supplied by the second PS?

The Io with volume controls has an active stage following the volume controls. It is not passive.

The second PS chassis makes the Io fully dual mono. One PS chassis feeds the left channel and the second feeds the right channel, with no shared PS functionality anywhere. For what you can expect to hear with this fully dual mono option, see the comments from Jim White that I quoted above.
All positive answers, in terms of the potential of the Io. I am rather surprised that the 2nd PS makes such a big difference; I would have thought that separate constant current sources and voltage regulators for each channel would be sufficient to max out the performance. Thx.
I have Io Eclipse now for almost a year. It is quiet but
not quite as quiet as Lamm LP2 or Fosgate Signature but
it is definitely not noisy.

My local dealer warned me that with regular use, stocked tubes may last only about a year. So far, I changed out the 4 first stage gain tubes with NOS. The stocked tubes are a little more quiet but sounded a bit lean. If you prefer extended, clear, detailed sound (but in no way analytical), the stocked tubes definitely will give you that. If you need a bit more body and warmth, you will need to look for some NOS. Finding good matched quads 12AX7 with low noise will not be cheap but I was told again by my local dealers that NOS tubes tend to last longer than the stocked tubes. I will have to wait and see if that is true.

I think the unit consumes something liek 400 watts at idle
so lots of ventilation space would be good.
Regarding heat generation. Is it at all possible/recommendable to place the power supplies in a cabinet (with an open back)? This works well with my Karan monos, but I do expect the Aesthetix units to get significantly warmer.
My Io runs much hotter than my friend's Karan new 2000 watts
monoblocks. Both Aesthetix units will generate a lot of heat
so I imagine that you probably want at least 3 if not all 4 sides open as much as possible.
I recommend you call Aesthetix and talk with Jim or Glenn about your proposed placement. They will have the experience across their user base to help you make that determination.

You can reach Glenn at (805) 529-9901

OK, thanks. May I ask (out of curiosity) what your friend is partnering the Karan monos with?
Sidekick, My friend is using his Karan with Magico Q5 and ARC 40th Anniversary pre. Can't comment much on the sound yet as he just had his listening room rebuilt and the amps are still not burn in completely yet but the bass and dynamic on his Q5 is just about the cleanest,tightest, most controlled that I ever heard so far.

Interesting :) I believe Karan has sold about 10-15 pairs of the M2000 world wide so far, which makes them quite exotic. I've had mine for about 2-3 months now. They do need quite some time to open up and "relax", as they did sound rather stiff and hard around the edges at first. They're also extremely transparent and a hard judge on their partners, which makes careful matching critical.
I had a regular IO single power supply that was just upgraded to the eclipse sig it went in for repair because it sounded so bad they needed to change so much the upgrade made sense, well it saved me some cash and I didn’t want any issues I wanted to sound great after all the previous issues and time I spent so I gave them the ok. Thousands of dollars later, got it back nothing but trouble the thing makes so much noise I can't listen to it! I borrowed a $500 little photo stage and it sounded so much better. Didn't have the depth the IO had but overall so much better only a little hiss. I am back about 15’ from my vandersteen 7 and I hear a pretty loud hiss and crackling in the the channels now ans then. Aesthetix then sold me more tubes thinking the tubs got bounced in shipping for several hundred dollars! Still makes the same noise quieted it down maybe 5%. I have spent no less than 80 hours swaping tubes and doing everything under the sun to make this wok because I am in it for so much cash. I am so frustrated with it I have not powered it up in months I would never buy this pre amp again. I think my system is just to sensitive for it maybe if I had less sensitive speakers but I hear everything and although the sound is big and live I can’t get past the noises it makes. I don't see how anyone can even here space and blackness over the pops and hiss.

I'm really sorry to hear about your troubles! But, based on the respons I've got from other IO-owners (as well as a great amount of customers cheering about the great service provided by Aesthetix in general), I'm also quite surprised hearing about your experience.

What does Aesthetix have to say about all this? I can't imagine them sending you a unit that's not 100% OK. Is it "only" a noise issue, or do you experience other problems with it sonically as well?
Hmmm... I suppose Io Eclipse could be a bit more susceptible to hum or whatever from interference elsewhere since the
case is mostly opened mesh grill. I had quite a bit of humming problem initially that went away after I connect a wire from the chassis to ground (same go for my Lamm LP2 but LP2 was a bit easier since it came with its own ground binding post). However, I am not sure about hissing and crackling noise though.
Had the IO Sig for a couple of years. I did find it noisy even with Jim's recdommended tubes. More important though is the perspective of the soundstage it throws. at first it sounds huge and it is. only when I switched to another phono stage did i realize that the IO is not so focussed and you might miss a more precise staging of the music. I put the IO n the same category as ARC phono stages - big sound highly impressive, but artificial if you want to replay a quartet on stage. Not saying it is bad or even wrong, but that is the characteristic of width and height versus depth and precision.
If a key requirement for your enjoyment is "dead silence" from the electronics, the Io will likely never satisfy your need. It is generating 80db of gain all from tubes. There are tradeoffs in doing this as compared to a solid state phono stage or a tube phono stage that uses a transformer gain step up device.

To my ear, the Io's all active tube gain sonics are consistently superior in naturalness, timbre and micro-dynamics - a sense of "life" to the music.

The downside to this all active tube gain is that a certain amount of tube rush is going to show through if you are using a very low output cartridge or if you are consistently playing at very high volume levels. The demand on the first gain stage tubes for low noise is significant and not to be underestimated. Even with "perfect" tubes, some people will continue to complain that the unit is noisy. For me, this is NOT the case. But, I've listened to vinyl and tubes for 40 years and am somewhat less concerned about dead silence in the background than others may be.

As to expressed reservations about soundstaging and precise imaging, I find no fault and only praise for the Io in these areas. I listen primarily to classical (orchestral and chamber) and small ensemble jazz. The ability to precisely and accurately reproduce the players and their instruments in space (horizontal, vertical and in depth) are high priorities for my listening enjoyment. And the Io is able to meet my very high expectations in these areas.
Has anyone compared the IO to the Rhea Sig? The latter, from my readings, hasn't had any noise problems and is a single chassis unit with great conveniences. Of course the actual sonics are what ultimately counts.
The Rhea Signature is very good. The Io Signature is materially better. I'd also prefer the standard Io over the Rhea Signature, particularly knowing that I can update it at any time.

Please don't misunderstand the noise point.

The Io is VERY quiet. There are NO "noise issues." It is simply a question of 80+ db of gain coming entirely from tubes. If you run the Io "flat out," there will some tube rush as compared to a solid state or transformer based gain stage device. At reasonable listening volumes and with reasonable output cartridges (e.g., 0.24mv and above), the Io Signature or Eclipse will be very quiet and one of the very best phono stages available.
Hi Rushton, while I'm not in the immediate market for an Io, I've had a peruse of the owners manual and was surprised by the unusually long warm-up before use. Specifically, I'm referring to these instructions:
A. Turn power on.
B. Wait at least fifteen minutes for power supplies to fully stabilize before unmuting preamp.
C. Begin playing record.

I'm used to tube phono and preamps muting for 30-45s after power-up - but 15min(?) seems a bit excessive/inconvenient. What have you found?
Tobes, I haven't seen these instructions. I've always just followed the lighting of the diodes on the face of the power supplies as my guide. But, from experience, if the power supplies are not fully stabilized, you can get some wonky sounds. For my system, I'm generally doing a 10-15 minute warm-up in any event for everything to stabilize (tube phono, tube monoblock amps, air bearing TT).
‎"The best phono stage we have ever heard"...on newsstands now, Io Eclipse wins 5 Stars from What Hi-Fi? Sound & Vision magazine in the UK - What an honor, thank you!
I have an original IO i purchased used from a dealer. Rather than send it back for an upgrade, i changed all the capacitors myself except for the 2uf big ones with TFT teflons. It was a heck of a job. Understatement of the century. But worth it. Tft have imroved everything i ever put them in to my ears.. The difference is significant and i love it. I am running it with an NOS spectral mcr at 0.2 on a basis ovation triplanar with io at 74 db into a reference 3 pre and have plenty of gain at 32. Speakers are currently 801s3. But also used dyn special 25 krell resolution 2.Also an orpheus h on a debut vector. The only noise i have is from a buzzing transformer in the power supply ( not through the speakers). Based on all these comments i will live with the buzzing rather than send it back..I can highly recommend the io . I want to hear the arc if i get a chance. I have had so many phono stages and nothing has come close to my aged ears. Tubes are mullard telefunken. Btw.
Hifi news(UK) has a recent review available online:

Hifi news and What hifi has only praise for the IO Eclipse, besides mentioning the practical issues as well as the potential back sides of the highly purist design.

I believe Stereophile has the IO Eclipse for review as we speak. Looking forward to that.
As for reliability, I’ve owned both a Rhea and IO Sig for over a year and have had zero issues with them. Concerning noise, I listen near field and have a fairly sensitive amp and only get a slight hiss with nothing playing using 74db of gain. I have found that both IO and Rhea are sensitive not only to tubes as others have pointed but also to cabling (phono, IC & power). Shielded cables are a must along with careful dressing. Albert Porter had Purist make a custom umbilical that he said help quite things down a bit. I think he still may market this.

I fall into the NOS camp for tubes. They are clearly better in my system and to my ears.

I plan on taking the road that LinnLP12 took when it comes time to upgrade. From what I can tell, the Eclipse looks like it was only a cap upgrade with a new chassis. I’m not impressed by the TRT Stealth caps in the Eclipse. I seriously doubt they are Teflon as they are the same size physically as the DynamiCaps they replaced. There are too many interesting options available not to have a bit of fun with this. Then there is the cost issue with the Eclipse versus the Signature. I think the cartridge loading and shunt resistors also look like low hanging fruit. I have Vishay TX2572’s in house for the cartridge loading position but haven’t gotten around to getting those installed.
You will not regret changing the caps (unless you choose the wrong cap :-). Everyone has their flavor of caps, I went through a lot of them for many many year. I would suggest you pick one that you know the after break in sound characteristics. Its an incredibly lot of work (understatement) but the effort will be rewarded. I dont change resistors or anything like that as I have made sound worse doing that. Some components are better than others, upgrade is just a term for "I want something new" :-). But the IO is what I consider really one of those special pieces. I did listen to it for a long time through a mod squad line drive passive and enjoyed it. Eventually went to an audio research Ref 3. The change was significant to my ears, therefore, i chose not to upgrade with the volume controls. For this reason, I agree with a comment that I beleive Albert Porter and some other person made online, go for the unit without volume controls and put the difference elsewhere.
Well, personally, I'm not very interested in turning a high end investment into a DIY-project. I prefer to put my trust in Jim White (Aesthetix :)
I disagree with Linnlp12 regarding the volume controls. Unless you already have a *very* good preamp, I see little reason to cash out for the Io unless it has volume and the extra line input. That means if functions as a preamp. With a DAC connected to the line input, you can have several sources connected to the DAC, and switch between them on the DAC. This way you can do without a separate preamp. Several users have reported that the direct link from the Io to the amp(s) sounds great. This is my experience also, not least from the extra input, which seems to have even lower distortion than the riaa/phono input.
Whoever had the Io Sig. and then sold it, def. is an audiophile. The Io is one of the best phono stages out there. Its imaging, texture, and dynamics are first rate. If you love chamber classical and jazz quartets you are in for a real treat. It is a music lovers dream. You still need great table, arm, and cartridge properly set up to get its maximum potential.
After much research and soul searching during the last couple of months, I'm going to make a final decision this weekend, where the final battle stands inbetween the discussed IO Eclipse and the Pass Labs XP-25.

In the right corner:

Aesthetix IO Eclipse with dual power supplies

+ the beauty of tubes
+ superior build quality and aesthetics (IMHO)
+ additional line input (for a digital source) making it a fully functional preamp (which in the end almost justifies the price...)

- twice as expensive as the Pass
- large boxes - 3 in total
- a LOT of tubes, which means a lot of heat and potential sources of hum and/or failure

...and in the left corner:

Pass Labs XP-25

+ half price compared to the Aesthetix
+ less (and smaller) boxes - 2 in total
+ less heat and less potential problems...

- no additional line input (which means you'll need a dedicated preamp for a digital source)

Your advice please.

Many thanks.

Aesthetix IO Eclipse with dual power supplies

Pass Labs XP-25

Your advice please.

Well, to be honest, those 2 Designs have absolutely nothing in common and are
2 totally different sounding reproduction designs.
When you think about those 2, you have absolutely no idea from anything but
you want to be accepted - based on their price tags - as a 'serious' Audiophile
:-). It is like rolling a dice for you. How about Parasound JC3 from Curl instead
of the Pass?
Roll it and have fun.
Well, if being a snobbish arse makes you an audiophile, I think I'll pass.
Sidekick_i, I have never heard the Pass so I cannot say. But I do know the Io, and do not think you will be disappointed. Great with rock as well as less dynamic music. Works well with my 0.5 v Titan i p-u. No noise problems after I got a replacement tube set from Aesthetix. Functios fine direct into my amps (Krell, now Atmasphere). Since I enjoy it a lot, I have shipped it for an upgrade, even if it costs a lot from where I live (Norway).
On the volume controls, I was using a passive mod squad preamp and was going to go after a placette. Then an ARC REF 3 came along. I never looked back. For a test, I put the mod squad back in. No comparison, the REF 3 all the way. I know the IO volume controls are not in back where they will mess with the impedance. But the combo is truly stunning to me. I have gone through many high end phono/non-phono preamps and this combo is the best so far. Many more to try while my hearing still exist. By the way if people talk tube hiss when you get to my age and have tinnutis, you have tube hiss 24 hours a day :-)
I would go for the Aesthetix, no question. Nothing wrong with Pass but once the "new" wears off of this acquisition and you settle in and listen day after day, you will appreciate what the IO and tubes do for long term listening enjoyment.

Linnlp12 comments about active versus passive are accurate. The IO is active but it's mate the Aestheitx Callisto presents a significant improvement in sound, a purchase you could make years from now with no penalty should you need the added flexibility.

That being said, I would prefer IO as stand alone solution and If two boxes are preferred, the IO with single power supply would still be the superior choice and clear performance winner in my opinion.
Thanks for valuable responses!

As I live in Scandinavia/Europe, the possibility of auditioning equipment on this level in my own home and system are extremely limited. Even so, I've managed to make most choices so far based on careful evaluation in my own home. In this case though (looking for a high end phono), it's impossible, as there's almost nothing available on my local market. So, basically, I have to make a decision based on listening on trade shows and auditioning the systems of my friends, partnered with advice from the hifi community.

So again, thanks for valuable input!
Sidekick_i, I thought I would add one more comment to support what Albertporter has said about the choices you are considering. As much as I try to find long-term listening enjoyment from the solid-state phono stages I've heard, I keep coming back to preferring tubes in my phono stage. For me, the sound is just SO much more natural and realistic - particularly with the Aesthetix Io.

With the volume controls, the Io makes a great standalone unit. I drive my Atma-Sphere amps directly with the Io with great results. When I sit down to listen, I am regularly pulled into the music, not the sonics. But it is the superbly natural sonics that allows that to happen.

Good luck!
The AR phono stage is good, but no way does it compete with the aesthetix.
AR...? Audio Research?
Sidekick- I think i responded to your query on another forum and based on your stated preferences, would probably lean toward the tube unit. And, although it is not the same as trying it in your home, could you devote a couple days to a trip to, say, London, where a dealer or two might be able to help demonstrate some of the units in something close to what you have?
If you are in Stockholm, please say hello to the people at that hotdog stand behind the Grand Hotel- it was always my first stop.
PS I had also suggested you try the ARC Ref as a sort of middle ground and perhaps if you did a trip to, say London, you could audition it as well.
Best of luck,
Bill Hart
Good suggestion Bill.

Even a brief listening session by Sidekick could be of great benefit.
Firstly Aesthetix service is first rated, Jim and Glenn are easy to talk to and helpful in everyway.
I have Callisto sgn and io sgn.
If I have the means I will upgrade to ecilpse. Forget about remote I am used to get up and adjust the volume.
Can I ask how is your Karan m2000 that is a power amp did it said class A in what watts ? How is your liking.
Re: "careful evaluation in my own home".
I could not agree more. Of course, this is the ideal. However, it cannot always be done. Especially when you move to a top level, and live in a peripheral place, e g Norway. So one has to make informed (hopefully) choices. So far, I have done well, aided - not least - by helpful discussions in this forum. Nine months ago I bought Atmasphere amps, never having listened to them, but having some experience with OTL on my desktop. They replaced a VERY highly regarded solid-state amp. At first I thought it was a flop. They needed run-in, and I needed to adjust my ears. Now, I am very happy with the new amps. I am also buying new speakers, fit for the amps, from Audiokinesis. Have I heard them? No. I buy them, based on the advice from people I trust. Likewise, I have shipped my Io for the Partial Eclipse upgrade (that is, minus the chassis), across the Atlantic, based on advice. Do I know it will work? No. But I am able to make *informed guesses* and that is not least thanks to all you fellow writers, here in this forum.
We all need to make a leap of faith in this process. And you are right, when there is a general, long-term consensus among folks with a variety of different, high quality systems, and input on appropriate related components, the risk is reduced.
O holter
I have listened to Callisto eclipse vs burmester, burmester is I think $28000
Same system in dealer's house . I told him I like Callisto better, more warm and involving. Surely to reach each ear. He did not disagree and said he is with me.
I started with the Io 13 years ago. It had the volume control which is ideal for my setup. Several years later, I upgraded it to the MkII and added the second power supply. Several years after that I upgraded to the Signature version. About 1 1/2 years ago, I did the Eclipse upgrade. Each and every step along the way, the Io got better. Better in terms of lower noise floor, better dynamics, better transparency, more detail, yet more flow and music.

If in doubt, start with a used Io and one power supply. If you like it, they are fully upgradable. As several have pointed out, the Io is very reliable, easy on tubes and the factory support is superb.

Tweaks I made along the way: switched the EL-34s in the power supply to KT-66, replaced the umbilical cables with higher grade wire and lots of shielding. Replaced the stock AC cables with Nordost cables.

The Io sounds best with XLR outputs, much better to my ear than the RCA outputs. If you can run your amps with balanced inputs, that's the way to go.
Old vinyl
Agree xlr so much better,
RE Io best output: XLR / balanced output sounded best with my Krell. I have not tested much with my new tube monos.

Io input (from pickup) is perhaps also best served by balanced cable? I have only used RCA / single ended (Kimber KCAG). Comments?

Oldvinyl, very sensible advice. That was my own way, and I've not looked back. How did you upgrade the umbilical cables (and was it worth it)?

Csngl, interesting. I've found I prefer the Io's pure tube amplification all the way, to others I've heard.