2. amps-preamps
  3. 1109994264

Any fellow VAC Phi 220 owners out there? Thoughts?

I am absolutely thrilled with my VAC Phi 220 monoblocks and was just wondering if any other Phi owners out here share my enthusiasm? These are the best sounding (by far) power amplifiers I have ever heard in my system, and I think one of the best amplifiers I have heard period.

The Phi 220s really do it all with my Vandy 5As, but the midrange and treble reproduction are a cut above any other amplifier I've had in my system. It is the first time I feel like I'm listening to pure music and not an audio system. It's emotional, engaging, and just sounds "right". The 5As simply disappear like never before and are extremely capable of revealing just how good the 220s are.

Sorry if I'm "over the top" with my comments on these, but VAC nailed it with these amps!

Vandertseen Model 5A- Bird's Eye Maple
VAC Phi 220 monoblock amplifiers
EMM Labs DCC2 DAC/preamp
EMM Labs CDSD- SACD/CD transport
Audioquest Sky 72V DBS XLR interconnects
Audioquest Kilimanjaro 72V shotgun biwire speaker cables
Silent Source AC power cords
Custom Power Cord Co. Model 11 Plus for 5A subs
BPT 3.5 Signature Plus balanced line conditioner
Critical Mass Systems platforms for EMM and BPT
Sistrum SP-101 platforms for VAC Phi 220s
fsarc
711smilin
513 posts
 
Are these class A?
tvad
9,467 posts
 
In this article from the VAC website, Kevin Hayes discusses his design philosophy and specifically mentions that the Renaissance series of VAC amps are class A1. Now, I don't know if that applies to the Phi series. That would be a question for Kevin. But, I'd be willing to bet the Phi series amps are based on the same basic design theory.
fsarc OP
148 posts
 
Indeed- they are Class A1. This is from my Phi 220 manual:

"The Phi Beam Power amplifiers are unique power amplifiers, and the most power and detailed in VAC’s history.

Excellent linearity is achieved without resorting to loop negative feedback, for a more natural, dimensional sound.

A total of four KT88 are used in Class A1. Uniquely, each is provided with a separate DC heater supply to ensure that no undesirable couplings occur; only the intended ideal signal path exists.

The input circuitry of the Phi is derivative of the unique Williamson circuit, which provides pure, direct coupled, inherently balanced input amplification and phase splitting. Type 6SN7/5692 octal twin triodes do the honors.

Two superb VAC output transformer, interconnected in a way that allows high power to be delivered with the sonic purity of low power devices, provide superb voltage/current translation, allowing impedances from eight ohms to as low as one ohm to be driven.

The main chassis is machined from thick aluminum. The separate power supply allows e.m.f. fields, switching transients, and mechanical vibration to be isolated from the audio circuits.

The high voltage supply utilizes dual choke pi filtering for extremely low noise.

The Phi Beam Power amplifiers are designed not to the latest fad but to substance, for the highest possible sound quality. Time spent familiarizing yourself with this manual will be well rewarded."
tvad
9,467 posts
 
Well, interesting experiment tonight. I went direct to the VAC Phi 110/
110 with the APL Denon 3910 and tried Zero Negative Feedback on the
VAC. Eureka! No distortion. Even though I had tried going direct to the
VAC with the APL, I hadn't tried it with Negative Feedback switched off.
I'm bittersweet though, because it tells me there is a mis match between
my First Sound Presence Deluxe II and the VAC, although the system
sounds terrific with the First Sound in the chain and with the VAC's
Negative Feedback enabled. Now, I need to devote some listening to
both variations to decide which is better.
711smilin
513 posts
 
Tvad, I thought you were gonna buy that TAD stuff, and retire from high end LOL. Guys I am still going nuts, as to which amp to get. The Cary CAD 211 Anniversary http://www.positive-feedback.com/Issue11/cary211.htm

or the VAC Phi. Any of you hear both?

Thanks

Steve
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