New to tubes

I thought that the Rogue Audio Cronus Magnum had 55 wpc, using 4 EL34's, 3-12AU7's, and 2-12AX7's. Tubed amps typically have a "warmer" sound to them, so they sound "fuller", giving the impression that they have more power, however, 55 watts is 55 watts/channel, not 60 as in your Rotel. Also, your speakers (?type?) may be presenting a "difficult" load for your amp depending on the crossover and how low the impedance curve dips. Generally, I have found in my usage, that the smaller signal tubes last 9-12 months, or a bit longer, and the power tubes last 2-3 years. You do not need to rebias your amplifier when replacing the small signal tubes. The sockets usually do not require any cleaning, rather the tube pins should be cleaned with a mildy abrasive cloth to rid them of oxydation and manufacturing debris. I trust this helps,

From my experiences, 12ax7's should last 2500 to 5000 hours, 12au7's a little longer. I never get more than 1500 hours out of EL34's. Also, EL 34's usually don't put out more than 20-25 watts each in Ultralinear and half that in triode. So, 4 tubes (2 per channel) is most likely 55 watts max.

Tube wattage has been stated as double that of solid state but it's a huge discussion in itself-I'm not touching that!

Now, with that said, every amp's volume will be different as to where the knob is as to how much volume. The gain from the phono sections will make a difference too. 9 o'clock vs. 12 o'clock is meaningless. Max volume is not.

For tube learning, google "joes tube lore" and go to sonic frontiers site/anthem and look for "a taste of tubes".

Yes, it does. Thank you very much for your advice.

As far as the power rating, Magnum is an upgraded regular Cronus; a Cronus on steroids, if you will. It has 4 KT-90 tubes, instead of EL34, hence its higher power. It has more upgrades as well, such as better power supply and upgraded internal components.

As far as the speaker impedance, my Totem Hawks have a nominal impedance of 6 Ohms and according to the manufacturer, very stable and never dropping below 5.2. The sound is still glorious; perhaps bass a little less tight than before but the highs and midrange simply heavenly.

I just sold my other tube preamp, but the difference between volume control settings on that preamp (two O'clock for loud)...and the preamp I still use is quite large (ten O'clock for loud)....same amps for both preamps.

Pretty common.

Dave

Double the power because of tubes? Your dealer lied.

what happened to the edit feature! :-)

the knob position thing isn't comparing apples to apples most likely. that could happen between any preamp/amp, integrated depending on the position of gain stages or ration of attenuation.

Is the difference in loudness (at same volume setting between two integrateds) only there when playing TTs and not when playing CDs? If so, what cart are you using? If low or meium output MC cart, that will explain the lower loudness because the phono in your Rogue Cronus is an MM phono set for 47Kohm loading and 150pf capacitance and with only 35dB of gain. So if you are using a low or med output MC cart, there is not enough gain in the phono section. If that is what is going on, you will need to get an MM or a high output MC cart. Let us know if you figure it out. Thx

Thank you all for your input and advice. I switched from the built-in phono section to my Soundsmith MM phono preamp with 48 dB of gain and even though I still have to turn the knob a little bit higher than before, it matters not. The sound is simply glorious and I am in heaven. "Byrd in Hand" is spinning as I'm writing this. I think I'm going to give my dealer a hug tomorrow...

I basically disagree with everything Mcfarland said. Tube amps don't sound more powerful for the same wattage rating as SS amps because tubes sound "warmer." Tube amps sound louder than an equivalent rated SS amp because tubes clip different than SS devices. David Manley postulated that tubes also sound louder due to their high voltage power supplies vice the low voltage power supplies used in SS amps (power tubes typically have somewhere between 300v-500v+ on the plates whereas around 50v is common for the power supply rails feeding output transistors).

Also, I find it interesting that McFarland's output tubes outlast his small signal tubes. As a general rule, high quality small signal tubes can last up to 10,000 hours and it should be common to get at least 5,000 from them. Output tubes usually cry uncle after around 3000 hours. The bottom line here is that your small signal tubes should always outlast your output tubes-not the other way around. Either McFarland has some wierd amp that is eating his small signal tubes or he is replacing them before they really need to be replaced.

Back to your basic question about why you have to turn up the volume higher on the tube amp than the SS amp to achieve the same level-it all has to do with the gain/sensitivity of the two amps. The output section of your tube amp probably requires more voltage from the preamp section to achieve full output than your SS amp which is why you notice you have to turn the volume up higher on the tube amp. It doesn't mean a damn thing unless you think you can never turn up your new tube amp enough to get the volume you want.

I have a Rogue Cronus Magnum, too. I think you have plenty of power for anything other than a barn. In my small listening room I can't go louder than 10:30 AM on the main dial.

I'm using a Rega P5 with a high output MM through a Lehmann Audio SE preamp, so there's plenty of signal.

If you have other cronus questions, feel free to drop me a PM.