I just read Art Dudley's column on the asl 805 explorer dt. It's an set amp. I am not a slave to measurements but 10% thd at rated power? I don't care if it is 2nd order harmonics that is still too high. Also having to correct bias during a long listening session is too much involvement for me. I'm heading for push/pull land. |
the Audio valve Challenger 115/140 also meets ur requirements, autobias, takes various tubes, including a sweet el 34. |
I have never heard the Explorer but I bought Hurricane from Divergent Tech directly. They offer free shipping & possibly 10% discount if you don't have local dealer. You can call Div. tech for local dealers. They are a helpful bunch in tech support and have good recommendation on NOS tubes that work well with their amps.
From speaking to the tech support at ASL, they say the 1009-845 is their best amp with the Hurricane second (if you need more power). The Hurricane has some amazing reviews and the 1009-845 is even better in my system.
Check this site out.
www.high-endaudio.com/RC-Amplifiers.html
I found their opinion of amps accurate but I could not agree with their speakers or CDP recommendations. According to the reviewer, Monsson does not quite have the magic of Hurricane. |
Here's another question about an ASL amp although it could apply to some other manufacturers as well. The Explorer 805 DT seems too good to be true. SET, 50 Watts, fair price and built in meter. Seems like a lot of power from 1 tube. |
Not being a tube god, I went to the ASL site and was further confused. How do you choose between the KMP Fox DT, Explorer 805 DT and Monsoon DT (a junior Hurricane). They are similarly priced and have different tubes. Any reason to pick one or the other?
Glai, any thoughts you have will be appreciated. Plus where did you hear the ASL amps? |
art audio concerto's are autobias, zero negative feedback, under $2K used. |
The Atma-Sphere amps, at least those made in the past decade, are extremely stable, you can even remove output tubes while they are playing (not that I recommend this). The two caveats in your situation are that although they can be run single-ended they are really designed to be operated in the context of a fully balanced system and that they don't especially like low impedance loads (the S-30 particularly).
SF amps can be serviced and/or upgraded by the Parts ConneXion which is run by ex-SF staff. |
SF is out of business for years, but Parts Connexion which is run by Chris Johnson, former SF founder, will continue to service all SF products. If you don't feel like shipping it all the way there, you can order schematic/parts and have your local technician work on it.
Mine Line 3SE developed the famous volumne pot problem. I ordered the parts, got instruction from them, replaced it myself in 2 hours. You can pay someone to fix it for less hour as well. |
I am extremely happy with Antique Sound Lab hurricane & ASL 1009-845. I have the 1009 driving Avalon Diamond and the Hurricane driving Cremona Auditors. They are reliable, easy to bias and do a great job. IMHO, they better CJ 60SE, BAT VK60, Cary V12. I have not heard Rogue 150. ARC is a pain because everytime a tube fails, it blows a resistor. |
Greenman, I am using the AI3A preamp. Don't really want to get into the balanced thing. Aren't OTL amps prone to stability problems?
Trelja, I am in the NJAS. Know Russ and Fr. Richard very well. Needed to expand my net on amp choices to the internet audiogon crowd.
Semi, the only thing about SF amps is they are no longer made and what happens if repairs are needed? |
That's interesting observation Chris made.
I had VT-100 Mk 1 & 3 in the past, a friend let me borrowed his Mk 2 for a week. I have also had Sonic Frontiers Power 2, 3, 2SE and currently own the 2SE in addition to BAT VK-75SE among others. Side by side with BAT VK-75SE, VT-100 Mk 3 sounded rough, lack delicacy, slow, congested, etc. I could not believe my ears, neither can 3 other of my friends. Bass was not any better, it was such a disappointment I sold mine after a couple week.
However, SF Power 2SE (or even the plain Power 2) comes close to BAT! Bass weight is significantly better than BAT, but BAT is faster in bass, or faster overall. Top end extension, delicacy, air, refinement are all top notch like BAT, but BAT is still a touch better and expected given the higher price and lower output. I also owned BAT VK-150 (not SE) in the past, SF Power 2 definitely sounds better than VK-150 overall.
This is heard in the same system that includes SF Line 3SE and Sonus Faber Amati Homage, no other variable changed.
And like what Chris pointed out, SF Power series allow you to bias individual tube from top like a true reference grade tube amp. Only in ARC Reference series do they allow you to bias each tube. Reason is manufacture cost and VT series single resistor bias scheme is a very compromised design. For SF Power series, you only need to check bias once every few months, very little work involved. |
Assuming the impedance doesn't drop appreciably below 8 ohms the Atma-Sphere M-60 II.2 could be an excellent choice and it is in your price range used. Extremely easy to bias, works very well with inexpensive output tubes (doesn't require matched pairs or quads), reliable and has the OTL transparency unmatched by any of the other amps you listed. Does your crossover allow you to run balanced? What preamp are you using? |
The ARC amps are out if your not into doing some work to bias....... This does cut down on your choices considerably. Maybe the amp you hould look at is the Sonic Frontiers, like Semi Say's. It biases from the top using LED's that tell you when your good to go. They are decent amps, and you can get them serviced by the Parts Connexion guy. I have owned one of these amps (Power 2SE) and ended up selling it for an ARC VT100II becouse I thought the ARC sounded better........ Having said that though, the SF is a lot easier to keep up with.
Chris |
you that listed lots of primo equipment. the boogie factor would be totally dependant on loudspeakers though. |
Hopefully, Russ (Rcprince) will chime in here - he owns these speakers as well. I am quite impressed with their sound of his, the imaging is haunting. And, the priest who designs them is also a member of the NJAS, you may want to ask him, if Russ can put you in contact with him - Father is very open and honest. |
Sonic Frontiers Power 2, better than ARC VT-100 of any versions in most area for less money used. |
Chris, I have an active crossover for that purpose. The overall system efficiency is about 88-89db. I have been known to play at realistic orchestral levels at times (90-100 db). The room is L-shaped in the rear and the length is about 25-27 ft with a 7-7 1/4 ft ceiling and the width is about 15 ft but there is an enclosed staircase on the right which reduces the usable width to about 12-13 ft. No need for balanced connections. As far as biasing is concerned, putting a screwdriver in a slot is as complicated as I want to get. Also I am 6'5" tall and about 300 lbs so crawling on the floor behind some amp while balancing some screwdriver and meter is out.
AudioK, I have a pair of Sforzando JL1 speakers. They are wonderful. Here's their website.
http://www.rtplinks.com/cgi-bin/redir.pl?std-112300-fyY38Hy3tI65-dR7CepwqS14l-17 |
The Rogue M-150 is a good choice. |
What speakers do you have? |
First, do you have a way to match voltage between amps? How are you crossing your system over (i.e. active/passive unit)?? I guess what I am trying to get at is: How are you going to match the levels between your satellites and the bass speakers?
How effecient are your satellites? How big is the room? etc.... Do you need balanced connections? Are you OK with biasing the amps or, do you need something that self biases?
Lot's of questions for you to think about (maybe you already have). Some answers: You might ad the ARC VT100 to your list; a great amp that can be had in mkII version for around 2.5k. The Audiovalve amps look pretty nice and have lot's of cool features. I have heard good things about them but, have never heard one myself. I heard a couple of BAT amps and they were definitely not my cup of tea (YMMV).
Hope this helps
Chris |
