I’m in the market for either a used or new tube integrated amp to drive my Lawrence Audio Violin SE speakers which have an AMT tweeter. These speakers have a sensitivity of 88db and minimum impedance of 6.4 ohms. The amp should sound warm and smooth without any treble glare. The amp must be also reliable since my previous amp visited the repair shop 3 times in 4 years. I do prefer it come in black and must be 7" or less. I appreciate any recommendations.
I have one of these in a second system and it would have no issues driving your speakers. Definitely a warm sound and built like a tank. The footprint is more than 7 inches. Did you mean height? That's less than 7 inches.
I saw this unit for sale also. I contacted the seller concerning the age of the unit or a serial number but I haven't heard back from him. I'm also considering a Rogue Cronus Magnum.
I would take a long, serious look at the Unison Research integrated as they would fit the bill perfectly either the all tube or the tube/hybrids. Great reputation for reliability as well.
I assume your 7" spec relates to height (as already pointed out). I also assume this height limitation is for limited clearance into a shelf system. If my assumptions are correct you will have a hard time, not because you might not find an amp less than 7" tall, just that even if you do, and it fits, you will not have sufficient clearance to dissipate the heat from the tubes. In an open rack you probably should allow 6" or more clearance from the tubes. FWIW.
Here's the scoop, I own a hybrid, the BAT 3000SE. I bought it used after selling the PL and wanted to try out a hybrid. It's a great sounding amp, very detailed and dynamic but I still prefer the lushness and sound stage of an all tube amp. Even with tubes in the preamp stage it's still a SS amp.
Look at the Raven
Nighthawk MK3, it's only 6.5" tall and right now is on sale Axpona show pricing. $ 3,000.00I listened to the Raven amps at Axpona last week and they sounded great and are made in the US in Texas.
I’d suggest the Rogue Cronus Magnum too, or a PrimaLuna integrated. I’d think that either one would work well with your spkrs. This may sound stupid, but I always just put the grills on my spkrs for recordings that are a bit too bright, because I just kinda think of grills like speaking with something like a paper towel in front of my face. But then again, it looks like grills may not be an option for your spkrs.
The best tube amp for you is the Stax SRM-007 LII, is smal and very good. 55w at 8 Ohm. He is specially made for sacd,and very good music sources. In Belgium 2390€. (One of the best high-end stores). It gonna make you happy !!! Have a nice Easter!
Did you enjoy the sound of the Primaluna Dialogue Premium and what type of power tubes were you using?
The Rogue Cronus Magnum could be a good option for you. It will have a different sound than your Primaluna , so you might want to give it a demo first. Especially if you were using EL34 power tubes in your PL. The new Rogue Cronus Magnum III uses KT120 tubes. It does come with a MM/MC phono stage. It also allows you to switch between Triode/Ultralinear ,which can be a nice feature like you had with the PL.
Tube amps need ventilation, no doubt that. I would never place one in a rack, on top of it, yes. Good luck with your search, ronrags, should be a few suggestions offered. Take your time and research whatever is...
The first time had to do with a short, the second time I’m not sure but the last time was a blown auto bias board. One of the power tubes was receiving 3 times the normal mv. Kevin questioned me why I was using KT77 tubes since he felt they can become unstable. The irony is he sold them to me!
@timo62
My preferred tubes were the KT77 and Cifte 12AU7. My local dealer is allowing me to demo the Rogue at home today so it should give me a good idea concerning the sound. I also called Rogue concerning using other power tubes and stated I could use KT77 tubes by reducing the bias to 30 instead of 35. They recommended I experiment with the 1 preamp 12AU7 tube before rolling any power tubes. The only tubes they don’t recommend are the EL34 or KT150.
I thought of buying a used BAT VK55 from a close friend here audiogon recently. The problem is my unit/ tv stand isn’t large enough to accommodate it. I owned separates years ago and prefer the convenience of an integrated amp with less cables!
This afternoon I brought home a Rogue Cronus Magnum 3 from a local dealer to demo over the weekend. After a 1/2 hour warm up, I played the same music I had listened earlier on the BAT. Here are my initial impressions:
-the soundstage is bit larger -the music is a bit forward as if I’m sitting a few rows closer -a bit more lush and fuller -bass not as tight but still good -the treble was a bit harsher and not as clear
So I checked the tube bias. One tube was at 34mv, the other at 36 so I adjusted both to the correct 35mv. The dealer suggested I try the 4 ohm tap as well as the 8 ohm. I removed the top plate and made the necessary wire adjustments. It sounds better on the 4 ohm tap as it did on the Primaluna.
Overall it it sounds a little better especially the treble. I emailed a fellow audiogon member who is selling his Rogue and suggested using a Cifte 12AU7 as the preamp tube. I used Cifte tubes in my PL and thought they were smoother than other various NOS tubes I had tried. So I’m hoping a Cifte or another NOS tube will do the trick.
As as someone mentioned above, there is a musical difference between KT120 and EL34 tubes. I did prefer KT77/EL34 type tubes than either KT88 or 120 in my Primaluna.
After 45 years it’s like starting all over again, comparing amps and then rolling in different tubes. Tomorrow’s a new day so I’ll start fresh and decide whether it’s worth investing in tubes again or keep the well made and nice sounding BAT amp and call it day.
Thanks for all your suggestions and recommendations.
I have this integrate designed by PrimaLuna, their sister company from the Netherlands and find it has excellent dynamics, tight bass and extended highs. Build quality is perfection.
Regarding proper ventilation and cooling of tube equipment, or class A amplification for that matter, everyone should consider a company called AC Infinity.
I own their Controller 8 and four of their 140mm fans. The controller comes with four zone monitoring/thermostat capabilities, four temperature probes and the fans are usb driven by the controller, are variable speed and are whisper quiet. Easy to setup. Fans are designed to draw air toward or away from the equipment, can be vertical or horizontal and the best part...they really work. The temp of a Pass Labs class A xa30 using one fan on each bank of heat sinks is reduced by about 30 degrees.
They work and the controller plus 4 fans ran about $160 delivered. Caveat...my cabinet has air slots at the very bottom and the very top so the air can escape, otherwise, you are just going to circulate hot air...which my wife accuses me of quite often. LOL. Peace.
Thank you for the info concerning the fans. I imagine they are quiet since they are designed especially for audio type equipment.
To all
I returned the Magnum 3 to my dealer after the home demo. I mentioned I didn't care much for the KT120 tubes and preferred the GL KT77 in my previous Primaluna. It so happened he had used KT77 tubes in store and replaced the KT120 then adjusted the bias per the manufacturer. Wow! The midrange bloomed, the brightness became smoother and voices became more organic. Not only was I surprised but also dealer and another customer plus we all came to the same conclusions. So I ordered the amp with KT77 tubes instead of the KT120. Once I receive the amp, I will then consider using an NOS 12AU7 preamp tube.
About 8 years ago I purchased a modified Jolida 502b for about $700 and subsequently modified it further to replace the 6550/KT88s with EL-34s. Sounds great and runs with less strain with the lower power tubes. I'd love to A-B it against a PrimaLuna or Conrad Johnson to see if there is much of a discernible difference (all electronics will sound different but of course I mean better) that would warrant an upgrade. Thanks.
Congratulations on your order of the Rogue Cronus Magnum III .
I prefer the sound of the EL34 tubes also. Seems like everything worked out for you in finding the right integrated amp. I did not realize that Rogue Magnum would allow the use of KT77 power tubes.
I appreciate the suggestion but used various power tubes prior and still love the warm organic sound of KT77. From what I read the KT90 does not fit my bill.
@rbstehno
I owned a H300 prior to the Primaluna. Nice sounding amp but once I heard tubes in my system it was no going back to a SS amp.
I used the Gold Lion KT77s in place of the EL34s, and thought they were great. I will say I never even thought to check, but I did not realize when using them that it would change the desired bias value.
I actually had a Rogue Cronus magnum with kt -120 tubes which I really liked but it didn’t control the bass, was to loose. Went to the Hegel h100 which I liked but didn’t have enough power so I bought a h300. I then bought a new pair of large Ushers and needed more power so I went with a new McIntosh preamp and ps audio bhk amp.
The Raven or the Rogue two well made tube amps and top notch service if and when needed. The Raven has low power make sure you buy high sensitive speakers .
The OP did not provide information regarding the size of the room in which the amp and speakers will be installed, or about listening habits and preferences.
From a need for a solution that is no more than 7 inches high, can we deduce that space is limited ? This may be important due to sensitivity of the speakers. 88db in a large room with a modest tube amp may not be enough power, but in a small(er) room may be sufficient.
Many good suggestions were made. My suggestion is a bit out of the box: Go vintage.
There are several models of vintage integrated amps, that once correctly restored, will rival the sound of new amps, at a comparable (or lower) price. Vintage amps tend to hold value much better than new.
Sherwood 5ooo series amps are extremely well regarded, and sound wonderful. Sherwood embraced a slimline design, and all power tubes are installed at a nearly horizontal angle, minimizing the height of the unit.
Fisher X202 is an outstanding amplifier, but will take up more space than a Sherwood.
Fisher X1000 is one of the best integrated amps from the golden age. 40wpc of EL34 power and an excellent preamp section.
Sansui AU series, and Luxman SQ series should be considered.
One can find examples of all of the above for less than $1000 and then budget another $500-$1000 for careful restoration.
In all cases I would recommend inclusion of a quiet fan behind the amp due to possible ventilation compromises inherent in tight rack spaces.
Go online and look at the Audio Nirvana EL34SE. It’s 7 1/4 “ tall, comes only in Black, runs fairly cool due to it’s oversized transformers, sounds AWESOME, and costs only $ 999.00. Easy return if it doesn’t meet your needs.
Although I cannot do a comparison I can say that I'm very much pleased with the Rogue Pharaoh I purchased one year ago. It's a great unit IMO. Customer service by Rogue has been superb when I had any type of question or concern. Plenty of power to drive most speakers easily. Very nice phono stage. Only thing I changed, I did replace the original tubes with some NOS Mullard s. I'm aware it's not the ultimate but it does quite nicely in my listening room.
I actually had a Rogue Cronus magnum with kt -120 tubes which I really liked but it didn’t control the bass, was to loose. Went to the Hegel h100 which I liked but didn’t have enough power so I bought a h300. I then bought a new pair of large Ushers and needed more power so I went with a new McIntosh preamp and ps audio bhk amp.
This hobby can be a vicious cycle. Component synergy is a must.
Thank you for your congrats. If the Rogue with the KT77 sounds as good as it did at the dealer I’ll be very happy. Hopefully with the addition of the NOS Mullard in the preamp stage I should obtain the sound I’m looking for.
I did look into the Raven and Quicksilver integrated amps but they only come in Silver. I’m also surprised the QS does not come with a remote. I’m always adjusting the volume especially playing a mixed bag of music from my server.
Thanks for the recommendations and I will consider if the Mullards don't work out.
I called Rogue for an update and the amp should be ready by the end of next week. They plan to install the KT77 and test the amp for 24 hours to ensure there are no problems before shipping. I also ask to have the 4 ohm taps connected prior since it sounded best when I demoed at home. They also answered my many questions on the phone. It's nice dealing with an American company that you can call anytime and they will immediately answer your questions.
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