Amp for Acoustic Zen Crescendo 2 ?

Wlutke,

Lots of great responses and insight! Over the past 3 years I have used 4 different amp set-ups to include Herron, Vac, Vitus and now the magnificent LM 508IA which is the best sound I’ve heard in my system at a fraction of the cost of the mentioned components. I could have lived with 3 of those components but didn’t think Vitus was a good match at all; very powerful, good sound-staging and imaging but had a warm sound signature and lacked dynamic impact.

I primarily listen to Classical Guitar, Violin, Cello with some old school Jazz thrown into the mix every once in a while and I can tell you that the LM can boogie too. The LM is so visceral, it produces lifelike images with spooky realism like I’ve never heard before and maybe it’s those 300B drivers creating that magic. The beauty of LM is that you get pin-point imaging, deep and wide expansive layered sound-stage with natural decay and ambiance retrieval that’s unbelievable.

If you like musical involvement, this amp will draw you into the recording with loads of texture, emotions and toe tapping happiness... Also, those of you with AZ Crescendo, bypass your binding post and discover another level of realism... Mod courtesy of Grannyring.

My Tubes:
Psvane 805
Sophia Mesh Plate 300B and EML 300B ( 4 days old)
Tung-Sol Gray Plates 6SUT
Stash of NOS 6SN7s
Synergistic Research Black Fuse

Room: 20Lx25Wx10H with entry ways on both left and right side of speakers; Gik 244s, Echo Busters and ASC Tube

@ Grannyring

- Do you hear any hum/buzz through your speakers a foot away? 3 feet away?

Slight hum with ear on speaker but can't hear it a foot from speaker

- Do the transformers make a mechanical buzz noise you can hear when the room is quiet? Not through the speakers, but simply emanating from the physical amp.

No

- How loudly do you listen when you go loud? Did you ever capture with a db meter?

Will capture my normal listening levels tonight when kids are in bed.

- How many hours are those 805 tubes good for in that amp before they need replacing?

They say up to 5,000 hrs. I have about 2,600 hrs. on mine with no issues; solid bias with no drifting

- Do you know if the amp is circuit board built or hard wired/tag strip. I could not find internal pics of your amp. Other LM amps are a combo of point to point wiring with only a two or three very small circuit boards.

All hand-wired point-to-point connections but there is a PCB with about 15 small Caps

- Finally, can you bypass the volume control with a direct input option on the back of the amp?

Yes; Pre-Amp in to bypass LM Line-Stage

Wig

@ Grannyring

Should have the Duelund DCA 16 ga in two weeks when back orders are in stock. Read a reviewer saying to single and run Deulund up both binding posts; bought enough to try as speaker cables.

Wig

Charles1dad,

With only 12 hours on the EMLs, they're a little more transparent but it took my Sophia's 56 hours for them to wake-up.  Looking forward to more hours but the XLS are not recommeneded with the 508 circuitry.

Wig

Here are my typical listening sessions with one of my favorite Acoustic Guitarist, Julian Bream.

- How loudly do you listen when you go loud? Did you ever capture with a db meter?

Measurement taken on my Tablet ranging from 73-83 db at my listening position.

Wig

@charles1dad 

Several other Vitus owners said the same thing and they were using 98 db high efficiency speakers; maybe that's why we see this amp matched up with Magico or YG Acoustics in reviews, a very dynamic speaker with aluminum type drivers.

After speaking with them, it peaked my curiosity since they were totally satisfied with their LM 219 IA 22 Watt SET and the 508 IA was recently released. Triode from Japan was on my list as well and is what Robert uses during shows (Mono Block) but the 22 Watt Integrated was over $9K and LM has the same build quality with twice the power solidified my decision... Not sure if there is a sound difference between 845 or 805 tubes? 

Wig

Many great attributes about the LM is that it sounds wonderful at low listening level, I turned it up a notch or two to simulate an average volume level but I listen typically lower and probably peaking at 75 db.

One of the most fascinating things I have discovered with output tube amplifiers even though they don't have the low end grip of the best solid-states, they make up for it with better mid-bass, sonic presentation with clean and taught bass; you actually hear more bass.

Definitely try as many of combos as possible to see which one suites your listening environment and taste.

I listened to both Vitus and LM side-by-side with the music I listen to the most and LM was head and shoulders above in every category and the LM has gotten much better with burn-in and tube upgrades; it's amazing how punchy this 48 Watt unit competes with a 350+ Watt power-house...


Wig

wlutke,

I haven't noticed a real difference in room temperature with the LM running 4-5 hours daily and I live in the desert.

Another piece of equipment that contributed to my sound system is Core Power Technologies Equi-Core 1200 Balanced line conditioner; the best I've heard in my system after owning 5-6 other brands.

Wig

So sorry to hear that!

ATB,
Wig