I listen to it. 1. Horrendous heat dispersion. 2. Not even close to the tone and glorious midrange of my 300b monos. The HF isn't as clear and the bass is fat but not very defined. Imagine a bodybuilder (805) vs. a triathlete (300b).
I used to have this amp. Heat is not an issue unless you are in the mid of summer. It only dissipates about 400W. Sound greatly depends on feedback setting. To get best sound you need to try all settings and find one you like most. What you described will happen if there is too much feedback for speakers used with it.
No, but I’d like to! From the couple reviews I’ve read, they have a sonic character I’d probably enjoy: “dense” is the word that keeps appearing. That said, they have an uprated plate-voltage spec—600V, I think?—which leads me to wonder if that’s a recommendation to hear these tubes at their most-linear best. (Recall some of the uprated KR and EML 300Bs, which were preferred only when Vp went beyond WECO spec.) Meanwhile, “dense” is how I’d describe the only Elrogs I’ve ever owned (or even heard)—a pair of 845s from the pre-Thomas-Mayer era: These were wonderful, but the point @Old Shatterhand made about heat dissipation (in his LM 805 amp) is well-taken here. Not much of the interior is visible, but note how brightly-lit the bottom of the tube is. Old Elrogs (at least the 845s) had their plate structures oriented toward the bottom of the envelope, which shortened lead lengths for noise-reduction. This negatively impacted heat dissipation, though—such that this amplifier’s top plate would hit 185F (85C) close to the socket and 150F (65.5C) most everywhere else. New Elrogs have plate structures that are located higher in the envelope, which apparently has solved this problem. Either way, thoriated tungsten filaments are pretty magical. For anyone not in the loop, this type of filament burns much hotter and whiter, meaning brighter. Here’s an HY69, which is similar to an 807—both with 6.3V filament/heater. HY69 has a directly-heated thoriated tungsten filament, though, which at 1.6A draws 75% more current than the 807’s 0.9A heater. You could definitely find your way around in the dark with this guy lit up! Thoriated tungsten’s power needs can increase to the point of being impractical to supply at home, though. The 217C half-wave rectifier (below-left), with 10V/3.25A filament, is probably in that camp—especially considering the need for two for full-wave rectification. (That’s why this one has been relegated to accent-light duty.) But in other cases (as with the 210s below-right) filament power is manageable and contributes to what I think of as a “superior” (to quote @zeitlos) output tube.
Maybe your room is bigger, but even in spring it heated up our 33qm living room. If 400 watt idle/heat dispersion isn't much, then I don't know what to call much. I forgot to add 3. It was humming, and no, not from/through the speakers the amp/transformer itself was humming. @Ontheone Harbeth SHL5 plus 40th.A.E.
Heat was not an issue in my 32 sqm room with 3 meters ceiling. I think you heard a broken amplifier. There was no mechanical noise from my sample and there should not be. I used to have another amplifier with 845 tubes. It started making humming noise when rectifier partially failed. It did continue playing music in that broken state.
Personally with my system I like 2A3s better, but the principle is the same with 300Bs. These amps have a very smooth, liquid sound - very natural sounding to musical instruments or even purely electronic music. Technically, they have a very benign distortion signature dominated by the 2nd harmonic which fattens up the sound. Unlike class A/B amps, these have no mechanism for generating crossover distortion, which is one important reason I use them since my horns would make any low level grunge very obvious and grating. I've found that full range horns make 300B amps almost mandatory. Some 300B amps are class A push-pull - this architecture tends to cancel the very distortion component which gives a SET it's sound (the even harmonics, 2nd, 4th). I'd stick with SET.
Right now the Feliks Arioso is on top of my list. Anything wrong with this amp from your point of view?
I recall NOLA representative demoing speaker (it was a special session at major dealer showroom) which rattled inside. Surprisingly no one noticed until I pointed that out to attendees of that presentation.
Were you asking me? I took a look online and they seem pretty typical in specs and such, so I'd assume you're OK with buying it. But I don't have any first hand experience with either that amp or that brand. The one thing to look out for if you're the owner of very sensitive speakers (>100dB/w) is residual hiss and / or hum being loud enough to be noticeable. But this is a caution with all SETs because of the nature of their power supplies.
Nobody who owns a SET setup, 300B or not, will tell you the truth. This is it: You listen to audiophile recordings of a single female voice against a light jazz accompanying background? Are you listening to male voices like singer/songwriter playing harmonica? OK, you are in heaven with that. Are you listening to complicated progressive rock, hard rock, full orchestra classical music, and opera, or any kind of music since 1977 on? Then you better have a different way out from that tube devil's pit and into the real world
Up until a few minutes ago, I was doing exactly that - loud. Granted, my system is actively crossed over with an MC-240 for the LF and the SET for the highs (500Hz up), so that evens things up considerably. Then, there's the four 18" subwoofers, but the Altec LF cabinets aren't high-passed.
A 300b can rock. If it has great transformers and you pair it with an efficient speaker it can play plenty loud and keep it's composure. Wrong speaker, too big of a room it can be a mess. 7 or 8 watts doesn't go far . I know I'm only using a few watts and it is louder than I would normally listen. Could it fill a large room and still have a big Soundstage? I doubt it. But in the space it's in it's plenty of power. Clarity and yes vocals are it's strong suit for sure.
My case: 89dB/W speakers in 300sqf space: 300B amplifier (8W) - no much success 845 amplifier (15W) - can play small jazz sets, women vocal sounds good, not much more. 805 amplifier (40W) - can play big band jazz, all kinds of vocal, classic and prog rock, but falls apart at crescendo in Mahler symphony. Solid state amplifier (300W) - can play anything including Mahler or EDM at club level.
I am of two, opposite, minds on this issue of sufficient power. Most audiophiles greatly over estimate the amount of power needed. But, a lot of fans of SET amps do the opposite and think SETs can deliver their magic under unrealistic conditions. It may be the case that a 300b SET will be good with 96 db/w efficient speakers, but, room size, acceptable peak volume levels, type of music certainly are important factors given the small margins available. I find large scale choral music to be a particular challenge. At crescendi, the music may sound a bit muddled when the amp is running out of gas. SET amps distort gracefully so this is not that unpleasant, so it is a limitation I can accept. I hear it with a parallel 2a3 SET running 99 db/w efficient speakers. I don’t personally see this as an overriding consideration, but, limitations should be considered.
I have auditioned the Rite of Spring, Guns and Roses, AC/DC, Slipknott, DIO, Motley Crue, Rage Against the Machine, Nightwish etc on 300B amps and would tend to agree with you that other amplifiers are "generally" better suited - SET is another matter - I listen to all of the above on my 2a3s - no issues - same for 211s same for the new 300B Audio Note Merishu Tonmeister - watts are watts and speaker sensitivity is speaker sensitivity - if the speaker is sensitive enough a SET will not have any trouble with this music. 85 db sensitive speaker at 1w reproduced 85 decibels. regardless of which type of amp is driving it. It takes twice the watts for every 3dB gain 85dB @1w 88dB @ 2w 91dB @ 4w 94dB @ 8w (the 8 watt SET is now maxed out). 97dB @ 16w 100dB @ 32w 103db @64w 106dB @128w (Speakers have a maximum watt per channel which are often around 125-200 watts and a maximum SPL) 109dB @256 w 112dB @512w 115dB @1024 w 118dB @ 2048 watts If one owns one of my speakers that are rated at 95dB SPL 95dB @ 1w 98dB @ 2w 101dB @4w 104dB @8 watts (The 8 watt amp is no maxed out - this would equal 70 watts with the 85dB speaker). 107dB @16 w 110dB @ 32w 113dB @64 w 116dB @128w 119dB @256 w If one owns a 105dB horn speaker 105dB @1w 108dB @2w 111dB @4w 114dB @ 8w (the first speaker that would 1,000 watts to get the same volume as this speaker with just an 8 watt amp) 117dB @ 16 w (the first speaker needs 2,000 watts to match 16 watts. There is a myth on internet forums about SET amps that misses half the picture - the other half is the speaker. The speaker is the "draw" the power draw. If it draws too much the amplifier - any amplifier - will be pushed beyond its operating condition and will suffer. A SET amp tends to sound "pleasing" or "Euphonic" when it distorts so a lot of folks give them a pass where SS clips hard and sounds awful. That Euphonic distortion usually means the treble is softened the bass becomes flabby or too soft. So long as you do not push the amplifier beyond its limits it will "do rock" or big-scale classical just fine. I have seen a lot of SET amps at dealers connected to speakers it really should not be connected to. And that is why they are playing Diana Krall - they're trying to make a profit on their 300B amp and also trying to make a profit on their B&W or Sonus Faber or Harbeth or Spendor or Magnepan speakers - and then people say 300B can't play Aerosmith at 105db - well no kidding.
It is crucial you have speakers that play nice with what ever amp you choose. I fully understood that buying this amp I am married to high efficiency speakers, and that's ok. This system sounds huge at normal listening levels. Clarity and intelligibility are strong points. Much more realistic than any push pull amp I've had.
And that is why I think people need to really listen for themselves with their music at their volume - in my case - I listen to all kinds of music at all kinds of levels but I no lonbger listen at stupid levels. My advice has been to buy spearates over integrated - get a preamp you love - get a power amp you love and if big scale and loud are music you listen less to - get a big Class D power amp. I have my class D 250 watts 8 ohm and 430 watt 4 ohm - if I really want to CRUSH. But usually those amps sit.
I'm listening to the late great Boston band Morphine right now and it sounds like Mark Sandman is here in the room with me ..... Piano and sax sound amazing as does the stand up bass.... at the volume I'm listening at its never strained or mushy. I would like to eventually get LaScala , that is actually a more appropriate speaker for this amp.
My Cornwalls are 102DB efficient and I typically listen between 65-80Db in a 350 square foot space. My current amp has a meter and I kid you not, the meter barely ever exceeds 0.1 watt. Yes that’s correct, 1/10th of a watt. From what I understand the La Scalla are even more efficient at 105 so I can only imagine how easy they’d be to drive!
Crossover board? That won't increase the sensitivity really; that is fixed by the woofer. Most sensitivity specs are exaggerated but looking at the driver and horn I might believe this one. Unison says their amps and speakers are matched so my advices are (1): Buy nothing you cannot return for a reasonable fee (2): More power never hurts for dynamic peaks. (3): Try also some high end solid state if you feel experimental. We really like our ATI 525NC then there's the Benchmark AHB2 and so on. See #1
That scenario (but with Altec Lansing speakers) is exactly what got me to become a loudspeaker engineer! I was fascinated, just totally sucked in. Though I learned enough to disbelieve Klipsch's sensitivity specs, they are still more sensitive that most, especially those Heritage models. I suppose they don't lie any worse than Zu or a host of others ha ha.
