330 monoblocks finally finished

Great to see new product from Audio Research!

George
 
"The Reference 330M Monoblocks from Audio Research, set to premiere at the High End Show in Munich, represent a compelling evolution in the realm of audio amplification. It's an interesting piece for audiophiles keeping a close eye on the technical space.

These are not your run-of-the-mill amplifiers. With 330 watts at their disposal, courtesy of carefully selected vacuum tubes, they’re engineered to deliver a sound that’s both powerful and pure—expect clarity and fidelity even when the volume is pushed.

The technology behind these amps is quite something. The new topology refers to a fresh circuit design, possibly aiming for more efficiency or better sound quality, or both. Then there's the tube regulation system that's all about stability and consistency, so what you hear is closer to the artist's original production."

 
Were they set up at Munich? If so anyone hear them?
 
Someone told me that they’re $90k/pair. That’s more in line with their competition.

I wonder what the Ref 750 SE costs now.
 
Someone told me that they’re $90k/pair. That’s more in line with their competition.

I wonder what the Ref 750 SE costs now.
They Are 90k a pair?
The 750 is 85k a pair ut seems. This is before tax?

But in europe it is 106k usd to 113k usd. Regional difference. (The 750..) Also, this must be with import and tax

Hmmm.

I suppose with the recent 4-5 year trend of making flagship speakers an easier and easier load for Amps ARC must have seen that not so much power is needed anymore. ARC seems to frem its their best Amp ever (the 330) . Still 750w tube power must be nice to have on the still hard to drive loadspeakers.
 
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The excellent and very useful site ARCDB.WS has a preliminary listing for the REF330M w/ARC press release and:

TYPE
Tube mono amplifier
INTRODUCED
2024
OPTIONS
-
MSRP (US NEW RETAIL)
$90,000/pair
 
I listened to the system with them quite a lot. It was in the Wadax room where the new Studio Player was driving them directly with Shunyata cables and power gear ( forgot which models) and a smaller pair of Magico Speakers. ( sorry dont know the model of these either but I think it may have been S3?)
They are 90k that was the number I was told and I was a bit surprised as I thought they were going to be less but alas this is 2024.
The system, as a system, sounded really very good and from what I heard at the show there was a ton of buzz about this room. There were two introductions and both IMO are highly anticipated arrivals.
The system set up by Brandon Lauer was excellent and was very easy to sit and get lost within when the room wasn't packed. I am not an ARC dealer but a long term fan and I hope that this entry restores some of the tarnished image of a great American company I grew up owning and enjoying. For those with the budget and the llove of tubes amps these sounded damn good to me.
 
After researching extensively the 330M in preparation for interview with Dave Gordon yesterday, I think it is a very interesting amplifier!

It is a very interesting hybrid, with tube output stage, and tube input stage, and buffer and driver stages solid-state. Part of the power supply is tube regulated, and part of the power supply is solid-state regulated.

I look forward to professional reviews and to WBF members reporting on their experiences with this new amplifier!
 
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FYI:

I've got two tickets for next Friday's event at Paragon in Ann Arbor MI, taking a friend from work.

Fri, Jul 12, 2024 6:00 PM - 10:00 PM

Audio Research's North American Launch Tour 2024: Reference 330M Amplifier​


The recent event for Octave Audio was enjoyable enough for a return despite what I suspect were phase issues. Paragon knows Audio Research, and I'm sure it will go off without a hitch.
 
After researching extensively the 330M in preparation for interview with Dave Gordon yesterday, I think it is a very interesting amplifier!

It is a very interesting hybrid, with tube output stage, and tube input stage, and buffer and driver stages solid-state. Part of the power supply is tube regulated, and part of the power supply is solid-state regulated.

I look forward to professional reviews and to WBF members reporting on their experiences with this new amplifier!
Pre-Covid at an Paragon demonstration/education event I did enjoy some Audio Research paired with the elliptically shaped Sonus Faber's. First time for me actually enjoying the sound from either of them. Typically I'm not an Audio Research guy, but an old bias should never color opinions of a new product line in my opinion. I'm hoping to be wowed but not overwhelmed when I hear the 300M's.
 
The circuit description indicates a pretty radically different design.
Yes, tube input stage but buffered with "tube like" bipolar transistors. Last time I checked the transfer function of a bipolar transistor was radically different from a triode. Then to a differential tube stage and then to a JFET driver stage. That's a lot of stages. Then regulation. SS regulation for the small signal devices and tube regulation for the output stage! Normally, you would see it the other way around because to tube regulate such a high power amp means a lot of regulation devices and heat....not sure that this possible with 6 KT170s and only a single 6550 as a regulator tube. Something must be missing from this description.
 
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Yes, tube input stage but buffered with "tube like" bipolar transistors. Last time I checked the transfer function of a bipolar transistor was radically different from a triode. Then to a differential tube stage and then to a JFET driver stage. That's a lot of stages. Then regulation. SS regulation for the small signal devices and tube regulation for the output stage! Normally, you would see it the other way around because to tube regulate such a high power amp means a lot of regulation devices and heat....not sure that this possible with 6 KT170s and only a single 6550 as a regulator tube. Something must be missing from this description.
@morricab Astute you are... Indeed, you could read the literature by Audio research, it is described there, no 6550...
Silicon Carbide Jfets..They (AR) go on by saying...
"Using JFETs for drivers also allows each tube to be biased individually: each tube has its own servo."

Lets quote the whole thing, shall we...

"
The Reference 330M is unique, combining new thinking, new design, and new parts with the best concepts from other Reference amplifiers. The new front end is a hybrid, using an ECC83 tube rather than a JFET at the input. The ECC83 has a buffered output, the buffering accomplished with special bipolar transistors that have tubelike qualities.

The second stage is similar to the 610T and 250, with a differential pair loaded with a DMOS current source. Rather than using a 6550, the output tube drivers are new Silicon Carbide (SiC) JFETs, which give the driver stage more headroom. The output drivers are bootstrapped by the output (both in the drain and source), providing even more headroom during large signal swings, with reduced input capacitance.

Using JFETs for drivers also allows each tube to be biased individually: each tube has its own servo.

Output tubes are new KT170s, which have increased plate voltage margin, peak cathode current, and plate dissipation. They sound wonderful, with great musicality. In a properly designed circuit, the KT170 provides an elevated level of performance that is unequaled.

The power supply features solid state regulation for the front end and tube regulation (6H30 and 6550) for the output tube screens and driver stage. It also has a Pi filter using a large choke, reducing output stage supply ripple.

The 330M is a fully-balanced amplifier, from input to output. Operation is Pentode only because this offers the highest performance. The rear panel includes balanced XLR and single-ended RCA inputs, 8Ω and 4Ω output taps, 12V Triggers, RS-232 control, tube hour meter, 20A IEC, and fan speed adjustment.

In addition to the GhostMeter®, the front panel includes Power, Meter light adjustment, Tube Monitor, and a reduced voltage standby mode to preserve tube life while allowing quick startup.

The Reference 330M is not Audio Research’s largest amplifier, it is our best ever. The presentation is vivid, immediate, and relaxed at the same time, with a musical completeness. Bass extension, control and weight defy its topology. To experience music through the 330M is the only way to appreciate how it serves the performance."

Yup, that should do it ...
 
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@morricab Astute you are... Indeed, you could read the literature by Audio research, it is described there, no 6550...
Silicon Carbide Jfets..They (AR) go on by saying...
"Using JFETs for drivers also allows each tube to be biased individually: each tube has its own servo."

Lets quote the whole thing, shall we...

"
The Reference 330M is unique, combining new thinking, new design, and new parts with the best concepts from other Reference amplifiers. The new front end is a hybrid, using an ECC83 tube rather than a JFET at the input. The ECC83 has a buffered output, the buffering accomplished with special bipolar transistors that have tubelike qualities.

The second stage is similar to the 610T and 250, with a differential pair loaded with a DMOS current source. Rather than using a 6550, the output tube drivers are new Silicon Carbide (SiC) JFETs, which give the driver stage more headroom. The output drivers are bootstrapped by the output (both in the drain and source), providing even more headroom during large signal swings, with reduced input capacitance.

Using JFETs for drivers also allows each tube to be biased individually: each tube has its own servo.

Output tubes are new KT170s, which have increased plate voltage margin, peak cathode current, and plate dissipation. They sound wonderful, with great musicality. In a properly designed circuit, the KT170 provides an elevated level of performance that is unequaled.

The power supply features solid state regulation for the front end and tube regulation (6H30 and 6550) for the output tube screens and driver stage. It also has a Pi filter using a large choke, reducing output stage supply ripple.

The 330M is a fully-balanced amplifier, from input to output. Operation is Pentode only because this offers the highest performance. The rear panel includes balanced XLR and single-ended RCA inputs, 8Ω and 4Ω output taps, 12V Triggers, RS-232 control, tube hour meter, 20A IEC, and fan speed adjustment.

In addition to the GhostMeter®, the front panel includes Power, Meter light adjustment, Tube Monitor, and a reduced voltage standby mode to preserve tube life while allowing quick startup.

The Reference 330M is not Audio Research’s largest amplifier, it is our best ever. The presentation is vivid, immediate, and relaxed at the same time, with a musical completeness. Bass extension, control and weight defy its topology. To experience music through the 330M is the only way to appreciate how it serves the performance."

Yup, that should do it ...
Just looked at the specs:

POWER OUTPUT
330 watts

TUBE BIASING
Auto-Bias

OUTPUT TAPS
4Ω, 8Ω

TUBE COMPLIMENT
(6) KT170 Power Output
(1) ECC83 & (1) 6H30 input
(1) 6550 & (1) 6H30 Power Supply

INPUTS
XLR & Single-Ended

CONTROLS
12V Triggers
RS-232 Remote Control

POWER SAVING
Standby Mode

WEIGHT
101 Ibs


Looks like it says there is a 6550 and a 6H30 in the power supply, no? Your bolded statement says something about the driver section. I only mentioned the 6550 as part of the power supply...
 
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Just looked at the specs:

POWER OUTPUT
330 watts

TUBE BIASING
Auto-Bias

OUTPUT TAPS
4Ω, 8Ω

TUBE COMPLIMENT
(6) KT170 Power Output
(1) ECC83 & (1) 6H30 input
(1) 6550 & (1) 6H30 Power Supply

INPUTS
XLR & Single-Ended

CONTROLS
12V Triggers
RS-232 Remote Control

POWER SAVING
Standby Mode

WEIGHT
101 Ibs


Looks like it says there is a 6550 and a 6H30 in the power supply, no? Your bolded statement says something about the driver section. I only mentioned the 6550 as part of the power supply...
Yes...
Point taken...

My apolgies.
I shall await a review and hopefully we will know
Just how it is designed, in more detail.
 
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r1.jpgr2.jpg

The 330M's sounded real good, but so did the 160M MK2's for half the price. Going to depend on room size and speaker selection, and I suppose what you can afford.

No glaring shortcomings, strong bass and musical.

One observation or excuse for not having more praise is that I do NOT like box speakers in general, the Wilsons did their best in vain to convert me. However I know these speakers so gauging the amp's contribution is easier than with unfamiliar speakers - so there is that.

Good amps, Audio Research continues to improve and I admit that their products over a decade ago just didn't move me (flat & dry). Much has changed for the better, but the prices are well beyond my reach, and that falls on me I guess - gotta earn more.

One thing I do NOT know for sure is how to report the soundstage characteristics, or better known as; apparently nobody appreciates a strong center stage as much as I do, and they all want the stage as wide as possible no matter what.
With the loudspeakers so far apart I cannot tell you much about depth and imaging, and are confined to frequency response or just natural flow.

I was sitting in the first row of both rooms, just off center by one seat. No panning or phase issues.
Overall a better evening than with Octave Audio, bless their efforts but that mystery about "phase" or "out of phase" is an issue I'd like to see fairly resolved.

To be fair the Audio Research evening was plagued with two of the building's three A/C units going out on a hot evening, but everyone joked about it. And late in the Room-2 presentation some server sync issues kept Harry Belafonte from getting us on the Banana Boat (Day-O), but the good tunes kept playing.
People were in a good mood because good music can do that.

The 330M, going back to AR's roots with all 3-stages tube everywhere (no J-fets if I heard right), but with a 4-layer circuit board. Some discussion on tube swapping, sounded like you will want to stay with the Tung-Sol KT170's (long story).

EDIT: The pair of silver 330M monoblocks were heard at the event are now owned by Paragon and one would think are up for sale - someone asked if the rep's owned them. I have always thought of Audio Research products as a silver face, and these did not disappoint.
 
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Just looked at the specs:

POWER OUTPUT
330 watts

TUBE BIASING
Auto-Bias

OUTPUT TAPS
4Ω, 8Ω

TUBE COMPLIMENT
(6) KT170 Power Output
(1) ECC83 & (1) 6H30 input
(1) 6550 & (1) 6H30 Power Supply

INPUTS
XLR & Single-Ended

CONTROLS
12V Triggers
RS-232 Remote Control

POWER SAVING
Standby Mode

WEIGHT
101 Ibs


Looks like it says there is a 6550 and a 6H30 in the power supply, no? Your bolded statement says something about the driver section. I only mentioned the 6550 as part of the power supply...

8/4ohm taps on such a powerful amp , Silly as they come ..!!!
 
View attachment 133731View attachment 133732

The 330M's sounded real good, but so did the 160M MK2's for half the price. Going to depend on room size and speaker selection, and I suppose what you can afford.

No glaring shortcomings, strong bass and musical.

One observation or excuse for not having more praise is that I do NOT like box speakers in general, the Wilsons did their best in vain to convert me. However I know these speakers so gauging the amp's contribution is easier than with unfamiliar speakers - so there is that.

Good amps, Audio Research continues to improve and I admit that their products over a decade ago just didn't move me (flat & dry). Much has changed for the better, but the prices are well beyond my reach, and that falls on me I guess - gotta earn more.

One thing I do NOT know for sure is how to report the soundstage characteristics, or better known as; apparently nobody appreciates a strong center stage as much as I do, and they all want the stage as wide as possible no matter what.
With the loudspeakers so far apart I cannot tell you much about depth and imaging, and are confined to frequency response or just natural flow.

I was sitting in the first row of both rooms, just off center by one seat. No panning or phase issues.
Overall a better evening than with Octave Audio, bless their efforts but that mystery about "phase" or "out of phase" is an issue I'd like to see fairly resolved.

To be fair the Audio Research evening was plagued with two of the building's three A/C units going out on a hot evening, but everyone joked about it. And late in the Room-2 presentation some server sync issues kept Harry Belafonte from getting us on the Banana Boat (Day-O), but the good tunes kept playing.
People were in a good mood because good music can do that.

The 330M, going back to AR's roots with all 3-stages tube everywhere (no J-fets if I heard right), but with a 4-layer circuit board. Some discussion on tube swapping, sounded like you will want to stay with the Tung-Sol KT170's (long story).

EDIT: The pair of silver 330M monoblocks were heard at the event are now owned by Paragon and one would think are up for sale - someone asked if the rep's owned them. I have always thought of Audio Research products as a silver face, and these did not disappoint.

Well This is the impedance curve they are throwing at those amplifiers with a 4ohm tap , i doubt all the short comings mentioned were all speakers, serious impedance mis-match into distortion there .. :)
 

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8/4ohm taps on such a powerful amp , Silly as they come ..!!!
Ask Jeff Fischel about his 300 watt monoblocks (ART 300). He ships everything hard wired for 4 ohms. Having owned both CJ and ARC big monoblocks, I know that either 4 or 8 can be chosen, but one will sound more pleasing to most. Jeff will rewire on request.

Speakers are not constant impedance devices. The complex impedance has frequency dependent real and imaginary components (resistance and reactance respectively). Tube output stages, with the exception of Futterman and related style designs, pair with their load via transformers. You can run as though the load is 4 ohms, or as though the load is 8 ohms… and in rare cases 2 or 16. Always a compromise … but loved by aficionados around the world.

What would you have done instead? Enlighten us.
 

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