Opinions Needed!


Here is the scenario: my secondary system consists of a Rogue Cronus Magnum 100wpc tube integrated amp, a pair of Golden Ear Triton Two speakers, a Sony HAPZ1ES Music Server, a Magnum Dynalab MD90 Tuner and a Sony SCD777ES SACD player. I also have all the audiophile approved connectors, power cords and power conditioners. I like the sound of this system very much, but I am not too thrilled with the bass control of the amp to speakers.

I listen to this system at least 8 hours a day, every day of the year. In the 1 1/2 years of ownership of the tube integrated, I have re-tubed the amp twice to the tune of 450.00 each time(some nos tubes and all purchased from Upscale Audio). The cost of the tubes is killing me!

I have been thinking of replacing the Cronus Magnum with a Parasound Halo Integrated Amp which is solid state and 160wpc. I like the idea of tone controls and the generous amount of inputs on the Halo and all the reviews have been glowing. I also like the idea of the built in ESS Dac as my Sony SACD player is getting long in the tooth and could benefit from the newer dac. I am driving to the closest dealer this coming Saturday to audition one and may be bringing one home with me.

If it weren't for the price of re-tubing, I would keep the Cronus Magnum as I can live with the bass not being as controlled as I would like. I think the Halo will be better able to control the bass. My question is, good move or bad move? I know this is a sideways step, but I really can't afford to keep buying tubes!

I doubt I will sell the Cronus Magnum, my plan is to rotate it in and out of the system when I need my tube fix.

Thoughts?

Thanks

128x128stereo5
What tubes are you using?  You shouldn't have to replace the small-signal input tubes that often, especially if they are NOS.  Usually they will start getting noisy or microphonic when they need replacing but I find NOS tends to last longer. 

Output tubes are another story.  Have you tried different output tubes?  I would not get NOS output tubes as they do not make as much a different as the input tubes.  I settled on JJ E34L's after trying KT120s, 6550, and a few others.  Bass is well controlled in my setup using smaller less sensitive speakers, and retubing costs well under $100 for a quad.  Something for you to consider especially since your speakers have powered subs.

The speakers have powered woofers, so wouldn't the amp just affect the upper bass? Could there be another problem? Sorry, don't know, just asking. Hopefully someone having experience with these speakers can answer.


Sounds like a good move, since you also like the onboard DAC with the Parasound.

Regarding the Cronus Magnum, you may not have found the right tubes to give you extended bass. Or the Cronus isn't able to optimally drive the bass frequencies of the Tritons. Are you using the 4 ohm or 8 ohm taps?

I had the same question as tls49.  I would not expect an amplifier change to affect the bass, as the woofers for the bass are powered by their own amp. 

I do sympathize with the cost of tubes, though, especially given your high usage of the system.  Going solid state makes sense, and the Parasound is a nice unit, with the DAC being a plus for handling redbook CD over the Sony's built-in DAC.  However, if you like the sound of the Rogue, do you have the ability to audition their Sphinx or Pharoh hybrid integrated amps?  As solman989 says, the small signal tubes in those amps should last a long time.  Downside to that is not improving the DAC over the Sony, which was good in its time but can be bettered these days.

As an aside, that's a lot of use for a "secondary" system!

Stereo5, recall this thread, in which you had posted:

https://forum.audiogon.com/discussions/primaluna-prologue-integrated-help-needed

Perhaps the reason your Cronus Magnum amp is having trouble controlling the bass is similar to the bass issue the OP in that thread was having using a PrimaLuna tube amp with the same speakers. Although the symptoms he experienced were different and more severe.

As you’ll recall, in that case a low frequency throbbing occurred when the volume was turned up beyond a certain point. The reason turned out to be that the PrimaLuna tube amp was not happy running essentially unloaded (i.e., into a very high impedance) in the deep bass region. (The impedance curve for your speakers is shown here: www.stereophile.com/content/goldenear-technology-triton-two-loudspeaker-measurements).

I suggested putting an appropriately chosen load resistor across the amp’s output terminals for each channel, which resolved the problem. It may be worth trying the same with your amp, although keep in mind that with your 100W amp you would need higher wattage resistors than the ones I suggested in the other thread.

Good luck. Regards,
-- Al

If you listen to it that much, tubes are not too expensive as a ratio to listening time.  If you like the tube sound that much it will likely be a problem going solid state at some point, sooner or later.  

I shouldn't have mentioned the bass as it really isn't a big deal.  The main reason is the cost of re-tubing.  Here is the breakdown:

4 Tung Sol KT-120 tubes cryoed                 232.00

2 Mullard reissue 12au7 tubes cryoed          66.00

1 RCA Cleartop 12au7 tube (preamp)          45.00

2 Svetlana 12ax7 tubes  cryoed                    66.00                

TOTAL     409.00

I stand corrected on the price, not 450.00.   The only nos tube is the RCA cleartop and thats only 20.00 more than a decent 12au7 tube.

I tried KT-88, KT-77 and EL-34 output tubes and I liked the KT-120 tubes best.  The sound of my amp totally influences the entire sound of the Triton 2 speakers, even though the woofers are powered.

Yes, this is a lot of use for my secondary system as my computer is in the same room and I work in my office where the system resides.  My main system gets little use, perhaps 2 times a month and only for a few hours.

Not interested in any of the Rogue hybrid amps, not a fan of class D and wouldn't even consider it.  For me it's class a/ab all the way.

I will be trying a loaner in my system but I wanted opinions if I am sacrificing too much for the sake of the cost of the tubes.

I owned a pair of Triton 2's and the bass was way too much for my room until I installed bass traps and then it was under control. I used a 6 watt tube amp to power them and they sounded very good. I currently use a David Berning designed amp and am hooked for life. If I were looking for an amp for those speakers I would look at the ZOTL 10, the tubes will last 10,000 hours or as he says 10 - 20 years under normal use.
http://www.lineartubeaudio.com/#home 
There are many other high-end tube dealers other than Upscale Audio.
That's an expensive RCA Cleartop; they are one of the most affordable tubes.

It seems to me that Golden Ear need to do something about the impedance issue with the powered bass portion of this speaker such that it is more friendly towards tube amplification. Based on what I read, and what I heard at one time in a dealership when this speaker was driven by a Macintosh tube amp in a large room that this speaker represents great value. 
The bass on my Zu Def4s is powered by an internal Hypex amp but it takes it’s input signal from the main amps. That does change with an amplifier change. I went from a tube amp to a class D amp while my McIntosh MC60s were being serviced and the bass character definitely changed, for the better. However I like the tubes for midrange much better, more accurate timbre etc.
If you can justify keeping both get the Parasound, Fun.
My room also needed better bass control and like the above poster adding bass traps helped immensely.

As someone said you should not be having to replace the small signal tubes, the 12ax7 and 12au7's twice a year, or even once a year for that matter. Small signal tubes should last a very long time, my own amp uses 3 6SN7's up front, different amp and tube type but still I've had the same 3 tubes in my amp for going on 7 years. You should be able to at least get 2-3 years out of yours, do you have access to a tube tester. Check to see how used up your tubes really are you may find you have a ton of spares on hand now.
I agree and not sure why you have to replace tubes so often. Is your bias set properly?  Kevin may charge a little more for his tubes but you can rest assured they are primo tubes as they have been carefully selected, matched and burned in. That is a great piece of mind.
Two thoughts regarding the tube life you have been experiencing:

1)If possible, check your line voltage with a **good quality** multimeter. If it is too high it could conceivably be shortening the life of the tubes. If it is out of spec (120 +/- 6 volts in the USA) the power company should take corrective action.  If it is near the upper limit of that range but not out of spec, you may want to consider purchasing a power regenerator rather than (or in addition to) a new amplifier.

2)I wonder if the cryo process to which most of the tubes have been subjected may be reducing their longevity. Not trying to start a debate; I honestly have no knowledge of the answer.

Regards,
-- Al

stereo5-

after the demo, report back your listening thoughts/impressions.
Whom is your nearest dealer/retailer?

Happy Listening!
The dealer is Safe & Sound HQ in Chicopee, Mass.  They are getting a silver unit in at the end of the week.  I will be auditioning the one on the floor and if I like what I hear, I will purchase the silver one.  I have 30 days to change my mind with no monetary loss other than shipping the amp back to them.  I have never been to this dealer before, so this will be a first.  I think they are mostly home theater but they are only 70 miles from me so it isn't too far a drive.
The Sony Hapz1es is the first piece of Sony equipment that I've owned since I purchased the Walkman way back when...
After trying out two Olive Media products,  a ReQuest Audio,  and BlueSound,  I have to state that the Sony meets my needs far better than the aforementioned.
It's easy to use,  it's sound is excellent....the 1TB drive is almost more than I need.  
This is a seriously good product for those,  like myself,  who don't want to wade too deeply into making my two channel rig a computer extension.