Integrated Amp Reviews

Mastersound 845 Compact integrated amplifier Specifications

Sidebar 2: Specifications

Description: Tubed integrated amplifier with single-ended, class-A output stage and auto bias. Tube complement: two Psvane HiFi Series 845B, two JJ ECC802, two TungSol 6SN7GTB. Inputs: two pairs XLR (balanced), four pairs RCA (unbalanced). Outputs: two sets of speaker binding posts corresponding to 4 and 8 ohm transformer taps. Negative feedback: 0dB.Power output: 30Wpc into 8 or 4 ohms (14.8dBW, 11.8dBW). Frequency response: 8Hz–40kHz (±0dB). Output impedance: 4, 8 ohms. Input impedance: 50k ohms. Input sensitivity: 1.0V RMS for full output. Power consumption: 202W.
Dimensions: 18.1" (460mm) W × 10.8" (275mm) H × 16.3" (415mm) D. Weight: 75lb (35kg).
Finish: Black-anodized with black-walnut side panels.
Serial number of unit reviewed: 22439. Manufactured in Italy.
Price: $10,495. Number of US dealers: 10. Warranty: five years.
Manufacturer: Mastersound SRL, Via Galileo Galilei 2/2 – 36057, Arcugnano VI, Italy. Tel: +39-392-997-6159. Email: info@mastersoundsas.it. Web: mastersoundsas.it. US distributor: MoFi Distribution, 1811 W. Bryn Mawr Ave., Chicago, IL 60660. Tel: (312) 841-4087. Email: cs@mofi.com. Web: mofidistribution.com.

COMPANY INFO
Mastersound SRL
Via Galileo Galilei 2/2 – 36057
Arcugnano VI
Italy
info@mastersoundsas.it
39-392-997-6159
mastersoundsas.it
ARTICLE CONTENTS

COMMENTS
ChrisS's picture
Submitted by ChrisS on May 6, 2023 - 9:41am

...no longer "here"!

https://www.stereophile.com/%20content/devore-fidelity-orangutan-o96-loudspeaker-jim-austin-september-2017

John Atkinson's picture
Submitted by John Atkinson on May 6, 2023 - 10:15am
Sorry about that. There was a wayward space character in the URL. Fixed now and the follow-up can also be found here.

John Atkinson
Technical Editor, Stereophile

DavidMA's picture
Submitted by DavidMA on May 6, 2023 - 9:44am

I enjoyed this review. But I'm always curious about how the review aligns to the measurements.

I've read through the final two paragraphs of the Measurements section of some of the more recent tube amps/integrated amps. Whereas the measurements for solid state amps often will conclude that this piece of equipment is "well engineered", the Measurements section for tube amps often has a statement along the lines of, "...the amp performs along the lines of what one would expect for a tube amp with zero negative feedback..."

The commentary always seems to imply that there are negative sonic consequences to these amplifier designs that are not commented upon by the reviewer of the equipment that a buyer should be wary of. It is as if Stereophile has two minds about tube designs. I did not find any reviews of tube electronics without this dichotomy.

I'll admit that I do not understand the testing section - I don't have a background to understand the tests and the interpretation of the graphs - If Stereophile has a lay-person's guide to the Measurements section and could make it available on-line, that would be helpful!. But I do read the last couple of paragraphs summarizing the Measurements as I am curious to see how the measurements align to the review. I find it interesting.

I have two amps - one solid state, and one tube. I enjoy them both.

John Atkinson's picture
Submitted by John Atkinson on May 7, 2023 - 5:52am
DavidMA wrote:
The commentary always seems to imply that there are negative sonic consequences to these amplifier designs that are not commented upon by the reviewer of the equipment that a buyer should be wary of.

That is correct. When I write "The amp performs along the lines of what one would expect for a tube amp with zero negative feedback," the measured performance predicts departures from a neutral sonic character that will be audible.

For example, the interaction between the amplifier's high output impedance and the loudspeaker's impedance modifies the speaker's frequency response. The high level of second harmonic distortion will add "warmth" to the amplifier's sonic signature.

This behavior, of course, may well be perceived as positive by a listener, particularly if it compensates for something elsewhere in the system. But it still needs to be pointed out in a review.

John Atkinson
Technical Editor, Stereophile

Jim Austin's picture
Submitted by Jim Austin on May 11, 2023 - 5:09am

I just want to make it clear that the opinion expressed by JA1 here, though very well-supported, is not universally shared.

It's true--no one connected with reality can deny it--that certain features in old-school tube amps cause departures from neutrality, especially with loudspeakers with impedance curves that drop below, let us say, 4 ohms, which is most modern loudspeakers. No one can deny it because they are measurable at clearly audible levels. But there's another school of thought--embraced by certain other Stereophile writers--that believes that something less tangible is retained in some such amplifiers that is lost in demonstrably more accurate ones. Such opinions are based on subjective experience--self-perceived connection with the music. This makes them literally irrefutable--they cannot be tested objectively, so they cannot be contradicted, which is annoying--yet (and this is my opinion, as the magazine's editor), in a magazine committed to subjective experience--to listening--above all else, such opinions must not be dismissed out of hand.

Edit: I thought I should add that the opinions/beliefs I'm referring to are held by many of the most experienced, devoted, passionate audiophiles. I do not take that lightly.

Jim Austin, Editor
Stereophile

Lars Bo's picture
Submitted by Lars Bo on May 12, 2023 - 1:38am

Thanks, Jim.

I agree: While "picky" and no surefire thing, good SET amps can be musically magical.

To quote Art Dudley (who felt SET could be something very special indeed (obviously, despite some drawbacks)):

"The fact is, there's an archetypal high-end audio sound and an archetypal SET sound. At its best, high-end audio sound is impressively open and clear, with deep bass, shimmering highs, and a flair for thrilling spatial effects; at its worst, it's lifeless, boring, constricted, undramatic, uninvolving, and incapable of any suggestion of flow in the music.

At its best, SET sound has the kind of punch and drama that can startle you out of your pants—plus real musical drive, momentum, presence, and tone; at its worst, it has no bass, no treble, and a level of coloration and sheer fuzz that could drive you out of the house after just a few songs." *

And:

"(Single-ended typically convey) An almost scary sense of presence on voices and solo instruments. Superb immediacy in terms of musical nuance. Equally superb drama, with the greatest dynamic contrasts available in home playback when mated to the right speakers. At least good to very good performance in terms of getting the notes and the beats right. A sense of flow and momentum in musical lines that is second to none. And an uncannily natural way with textures and colors—that beguilingly beautiful, gooshy feel that makes it easy to forget you're listening to electricity imitate people playing music." **

*https://www.stereophile.com/artdudleylistening/1107listen/index.html
**https://www.stereophile.com/content/listening-25-page-2

Jim Austin's picture
Submitted by Jim Austin on May 12, 2023 - 7:26am

Are you Lars Bo the musician? I suspect that this is a fairly common Danish name.

I've noticed an interesting phenomenon: These comment threads are carefully monitored by denizens of a certain hi-fi discussion site. Whenever I write anything here, especially if it seems to contradict one of our reviewers, my comment is copied and posted on that other website and potshots are taken. Many of the posts are ignorant and poorly informed. Almost all are ungenerous. A few are intelligent enough but lack wisdom. I thought I'd write a little bit more and see if the new information provided here is conveyed.

I have no tubes in my main system. When I wrote what I wrote above, in my reply to JA1, I was not describing myself but others whose views I respect. I'm not a tube guy. My main reason is that tubes are unreliable, which undermines my confidence in my system: Do I have a tube going bad, or is it something I ate?

There are many passionate audiophiles--again, not me--who have been on a lifelong journey seeking the best sound--the most musically expressive, humanly communicative sound. They are like artists, or, at a minimum, seriously engaged art lovers, people for whom music is daily sustenance. They relate to their music (and musicians), via their hi-fi systems, in a deeply human way. A lifetime of listening has made them astute observers, far beyond what most of us, who dabble in a hobby and limit our thinking to DBTs, will ever achieve.

When they say there's something going on beyond second-order distortion and output-impedance-induced deviations from neutrality, I take that seriously. To repeat: This is worthy of respect.

In serious pursuit of a musical connection, some may choose to limit themselves to verifiable fact--to approach the reproduction of recorded music as if it were an intellectual exercise. Others treat it as an art form--one they are deeply committed to. In pursuit of connection to music, each approach has merit.

Jim Austin, Editor
Stereophile

Lars Bo's picture
Submitted by Lars Bo on May 12, 2023 - 8:27am

Hi Jim,

Yes, Lars Bo is not an uncommon name in Denmark (either as a given or full name). I do play various instruments, though only for my pleasure for many years. But I spend way more time listening to and engaging in playback music (mostly as an art form you describe so well).

I agree with you: I have many friends whose approach and gratification in hi-fi are somewhat different than my own. Once in a while, some may even not like Bourgogne... We can discuss our "paradigms" and preferences passionately, but genuine interest in and respect for each other's perspectives make all the difference.

georgehifi's picture
Submitted by georgehifi on May 6, 2023 - 12:48pm

JA what's with the Mars attack test sweep tones automatically played in the background when the measurements page on this amp is first opened up?? Or is it the new audible intro to say we're now in measurement mode?

Cheers George

John Atkinson's picture
Submitted by John Atkinson on May 7, 2023 - 5:39am
georgehifi wrote:
JA what's with the Mars attack test sweep tones automatically played in the background when the measurements page on this amp is first opened up??

What browser are you using? The audio file - the recording I made of the low-level sound the Mastersound amplifier made when I measured its frequency response - should only play when you click on the "Play" button.

John Atkinson
Technical Editor, Stereophile

teched58's picture
Submitted by teched58 on May 7, 2023 - 9:06am

Yes, JA1, the Mars Attack of whistling not dixie autoplays for me, too. I'm using Chrome on Win10.

JRT's picture
Submitted by JRT on May 7, 2023 - 10:10am

...on Chrome browser on Android.

Charles E Flynn's picture
Submitted by Charles E Flynn on May 8, 2023 - 10:26am

Safari 16.4.1: File does not appear on the Measurements page at all (!)

Brave Version 1.51.110 Chromium: 113.0.5672.77 (Official Build) (arm64): File autoplays and its controls do not display properly.

Firefox 113.0 (64-bit): File played only when Play button was clicked.

John Atkinson's picture
Submitted by John Atkinson on May 8, 2023 - 12:16pm
Charles E Flynn wrote:
Safari 16.4.1: File does not appear on the Measurements page at all (!)

Brave Version 1.51.110 Chromium: 113.0.5672.77 (Official Build) (arm64): File autoplays and its controls do not display properly.

Firefox 113.0 (64-bit): File played only when Play button was clicked.

Thanks. Webmaster Jon Iverson fixed my buggy code. The file now plays correctly in Safari as well as Firefox. Don't have Chrome or Microsoft Edge installed, however.

John Atkinson
Technical Editor, Stereophile

Charles E Flynn's picture
Submitted by Charles E Flynn on May 8, 2023 - 12:40pm

You are welcome, and thanks for letting us know that the code has been fixed.

georgehifi's picture
Submitted by georgehifi on May 7, 2023 - 4:19pm

It's kinda good, like having Sheldon Cooper intro you into the believable section of Stereophile.
To have this when you open up measurements page, reminds you that your now leaving the subjective and entering the objective part of the review.
BTW mines Chrome also on Win 10.
Cheers George

georgehifi's picture
Submitted by georgehifi on May 8, 2023 - 4:28pm

I liked it, an audible que that you were now entering into the realm of reality/truth, without any subjective fairy tales to sway you.
I say bring it back JA!

Cheers George

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