Bought an Aesthetix Rhea! Tips? Tube suggestions?

Replaced a Heed Quasar. Incredible piece really and took quite a step up to meaningfully beat it.

 

In the meantime, here are some detailed pictures of the unit. (not mine)

Click on them to get full-sized versions.

 

A couple more.

 

All that to make a tiny little cartridge sound good. Amazing really. And retail this cost 3X my cartridge (Soundsmith Zephyr STAR). I guess this is the big week!

 

I believe Thomas Edison would be truly amazed and dumbfounded at how far his technology has been taken! And how it not only still survives, but in 2019 is still being refined and improved!

 

Can anybody give their thoughts on the built-in MC cartridge demagnetizer?

Does it actually do anything easily noticeable or is mostly just bologna?

 

They definitely work, but as referenced in the Stereophile review, some cartridge manufacturers (namely Van den Hul in the review) feel the mechanical ones are better, such as the old Cardas sweep record. I think the reasoning is that with the electrical ones, the more you use it, the more often it is needed, but that's not based on my own experience, I've only used the Cardas record, and can't remember the last time I used it.

 

Well, got the unit but barely had the opportunity to listen to music with it.

There was loads of noise and it was clear some tubes were microphonic. Replaced all the 12AX7s tubes with the RCAs I bought but they're *all* microphonic and severely so! They're going back immediately! *AND* the seller shipped all the tubes without BOXES! Wow.

Since I noticed the 6922 tubes were Electro-Harmonix and its no secret I find they are the absolute worst tubes on the market, I replaced those with the Amperex 7308s I bought and the problem is now resolved!

Could only listen for 2 min before the wife hit the sack but vocals were quite nice and holographic. Looking forward to tube-rolling with this unit.

 

I can try to put you in touch with someone I know who I believe is also in Toronto, and has an Io with multiple power supplies. He has a lot of very high grade tube preamps and phono stages (Marantz 7, Marantz 1 consolettes, etc.) and is a tube horder- he may be able to help you on tube selection and sourcing. He sent me a very nice matched pair of Tele ribbed plate 12Ax7 for my amps. I rolled 6922 tubes some years ago, and wound up with Telefunkens there too; the NOS Siemens was extremely linear, but had a less holographic character than the Tele. Just PM me and I'll try to put you in touch. As far as I know, he is not on this board, but a very nice guy.

 

Thank you so much for the very generous offer!

The problem isn't so much sourcing the tubes as much as them needing to be as devoid of microphonic and noise as humanly possible. Wonder if there are dealers who specifically test for this.

 

I’ve bought from three different dealers and all test for both. Not sure about Canada and such with shipping etc.

None of the three are what I’d call “cheap” but I’ve been mostly pleased with all three.

Andy bowman at vintage tube services
Brent Jesse
Upscale audio

Obviously the phono stage is most susceptible to this stuff so let me know. Upscale doesn’t ship unless you tell them what you’ll be putting it in.

How was the sound?

 

So...

What’s the latest?

 

Getting some Telefunken tested for noise & microphonics. Should have them in the next couple of days.

Curious to hear what change they'll bring to it. Stay tuned...

 

WOW! Congrats! looks like an amazing unit.

 

Kevin Deal should be your first choice. Nobody tests tubes more thoroughly than he does.

 

I own some tele 6922s. And frankly, they are not my cup of tea. They were not sweet-enough sounding for my taste.

 

+1

 

I assume the teles he is getting are 12AX7s, not 6922s. For those Strat likes the Amperex 7308s (USA), and I concur.

 

Exactly right.

 

I have heard this unit several times, but it was a few years ago. I enjoyed it at my local dealer, who told me that he only truly loved it when it was the ‘Signature’ version. He felt that it then became the class leader in its price range. He used it as his reference unit for 2-3 years. I have been told that you can upgrade the standard model to the Signature model.

I would use it and enjoy it at the standard level and upgrade when your budget allows. I really have never heard a bad thing about it. Enjoy!

 

@TarnishedEars & @IanL

It begs the question... In your opinion, what is the sweetest 12AX7 you've heard?

 

There is no one tube which qualifies as "the sweetest". And a tube which gives the best results in one amp or preamp will not always sound great in other designs.

For example, of the current production tubes, I love the lower midrange on the Russian Gold Lion 12ax7s. But the upper mids on this same tube are a bit recessed IMO. However the Opper mids and top-end of the current production TungSol 12ax7s are both sweet and extended, but the bottom-end is a bit thin on these. When cascaded (one following the other) the combination of these two is heavenly in my SP8. However many preamps don't have discrete tubes for different gain stages, which can make cascading of different tubes impossible on many designs.

In other designs I love the sound of the EI 12AX7s. But in some applications these can sound too bright. In some non-phono applications, I have loved the sound of some 5751s. And actually the current production Russian 5751s sound really nice IMO. I also have some other NOS favorites which I am reluctant to mention though lest the semi-affordable supply suddenly all vanish as a consequence of my recommending them on the internet. I simply can't afford to pay $200 a pop for a tube, so I normally go for the best sounding current production tubes whenever possible.

However, I prefer tubes with a bit more sparkle than do many people. If you need dull and dreary sounding tubes to tame an out-of-control tweeter, then you should probably ignore my recommendations because I really like sweet yet extended highs.

 

The Rhea was voiced using current production tubes and relies on them being EXTREMELY quiet and devoid of microphonics. This can be an immense challenge when dealing with NOS tubes. My new tube source had to go through *40* Telefunken tubes to find 4 matching ones fitting the Rhea without any noise.

In the 1st gain stage, they added a little bit of texture but some high-end energy I couldn't dial out eventually causing ear fatigue so I will likely try them in the 2nd gain stage to see how they behave.

Meanwhile, I'm getting some Mullard ECC33s on the weekend for use with my Line Magnetic 508-IA amp and am hoping it might assist in smoothing things over. Perhaps the combination will yield a terrifically addicting result. That is my hope, anyway. Otherwise, I'll have to look elsewhere.

I was thinking of some triple-mica RCA 5751s but am unsure as to whether they would likely sound better in the 1st or 2nd gain stage. A number of people reported good results with GE 5751s but I've never been a fan of GE tubes, hence why I'm leaning towards the RCAs.

Before returning the 1950s RCA 12AX7 long plate tubes, I did do a 2-min test drive with the volume low enough so that feedback wouldn't occur and was disappointed to hear very little bass though there was some of that airy RCA magic in the sound. Nevertheless, I don't believe these will work to my liking in this preamp which will be a first for me. They have traditionally sounded utterly wonderful in every device I have tried them in.

I'd be curious about trying Blackburn-era 12AX7 Mullards in the 1st gain stage. The current production CV4004 has been praised but I am also wondering how an NOS version of this tube would fare. Experimentation with this phono preamp is the key to making it sound its best.

So far, I'm liking what I'm hearing with the stock tubes, minus the 6922 slot which I replaced with the Amperex 7308. That change made a BIG difference!

 

As TarnishedEars said, it does depend on the particular application. But when I had vintage gear (McIntosh MC240 and MX110z, and a Fisher 500B), those Teles you got were king. The 3D presentation and overall balance were perfect. Especially in the phono section of the MX110. But I am running all modern gear now (except my turntable) and I am not a fan of the Teles in my integrated amp at all. Same problem you described, the highs are too fatiguing. It was pretty disappointing, because the first thing I did whenI bought my amp that used 12AX7s was order a perfect pair of NOS Teles based on my past experience with them.

I ended up very happy with a pair of Mullard 10M 12AX7s. I don’t tend to buy tons of tubes and compare them all. Instead I do tons of research and come up with a short list of what I think will be the best bets for my taste. The 10Ms immediately sounded wonderful in the context of my other tube choices.

I recently bought a pair of Raytheon 5751s to try. They are also wonderful! More linear and neutral than the Mullards (or even the Teles). I liked them enough that I have just left them in place the last several months. I’m not sure which I prefer. Not sure I care. Music sounds great, if slightly different, with both of them. I am using them in my preamp stage though, so not sure how/if they would work as well in a phono stage that calls for a 12AX7 specifically.

 

Interesting that your experience mimics mine.

Something else that I need to point out is the Rhea was voiced using current production tubes. My vast personal experience is nothing will ever sound as good as a high-quality NOS tube but since the Rhea is so violently reactive to the slightest amount of noise and microphonics in tubes, obtaining perfectly silent ones of any model can be quite challenging. The 40 Telefunkens which needed to be tested before finding 4 the Rhea would accept without issues should be representative of just how much of a fuss the Rhea makes about the littlest amount of imperfections other devices would ignore.

I'm the exact same way, actually. The 10Ms seemed interesting but they are quite expensive and the Rhea requires 2 sets of matched pairs. The first two pairs have the most effect on the sound but it would mean I'd need two sets of matched 10M pairs. I'd estimate it'd cost about 1K to get that. That's why I'm starting to lean on the idea of perhaps trying some RCA 5751s as they're cheaper and there have been some who've stated the GE 5751s sounded great... but I'm no GE tube fan so the RCAs might sound just as good if not better. The triple mica design will surely help in keeping noise and microphonics at a really low level.

I'm aiming for a sweet lush sound so neutrality wouldn't work for me in this context. As mentioned above, the Rhea would need exceedingly quiet tubes, though the 10M series was made specifically with that in mind (as well as lasting much longer than regular tubes). I've read some feedback about how using a 5751 would theoretically alter the RIAA equalization scheme and therefore change the sound signature somewhat but in the end, I only care about whether *I* like the sound so I might give it a go. Too bad you're not local. It would be nice to try the 10M for 5 min in the Rhea if only to get an idea of what that marriage would sound like.