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Grant Fidelity B283 MKII Tube Processor - MSRP US$225.00


List Price: USD $ 225
Price: USD $ 190
Dimensions: 20 cm × 18 cm × 16 cm
Weight: 7 lb

In-stock now for immediate shipping. 

This MKII version of the best-selling Grant Fidelity B-283 tube processor uses 6SN7 tubes which are commonly used on high end tube audio only.

Compared to the 6J1 version, it offers you more refined sound and works better with mid or high price range solid state system, plus you have endless list of 6SN7 current production and NOS tubes to roll for different sound.  If you have a budget sub $2,500 or vintage style system (equivalent values, speakers, amp, source CD player) , the original B283 would be sufficient. If you would like to explore more about tube hi-fi and tube rolling, the B283 MKII is a perfect small investment for you to venture into tube audio and learn all about tube rolling. 

The Grant Fidelity Tube Processor is designed to transform your solid state audio signals into the much more pleasing musical sound offered by tubes. The B-283 is earning a reputation as low-cost 'Magic Box' among musicians, audiophiles and people who simply love to listen to great music. The B-283 MKII is simple to operate, can install in your system in many configurations and has many uses such as:
 
  • Solid State CD Player Processing. Simply patch your CD Player thru the B-283 MKII and into your amplifier/receiver for warming up and correcting what some call the digital harshness of CD's.
  •  Home Theatre / DVD Player Processing. Initially installing on the 'front L&R' outputs of your DVD Player will improve the sound of your main speakers, especially with music DVD's. Another B-283 MKII can be added for the Centre and Sub channels for a clearer Centre channel and a warmer solid bass for your Sub-woofer.
  •  Pre-Amp Processing. Simply patch your pre-amp output thru the B-283 MKII to your amplifier and all of your sources (CD Player, DVD Player, Turntable, Tuner etc) will enjoy the musical benefits of tube processing. This can also be achieved on most good stereo / home theatre receivers / amplifiers by patching the B-283 MKII thru their pre-ins and pre-outs. Note that when running the B-283 MKII between a pre amd power amp you need to have properly grounded home wiring. Improper gorunding will cause the B-283 MKII to introduce hum into your system. When using the B-283 MKII after a pre-amp you need to have sufficient gain from the pre to drive the B-283, suggested you have volume control on your amp.
  • MP3 / iPod Players which compress the musical information, especially harmonics to achieve small file size. The B-283 MKII can recreate the missing important even order harmonic information from MP3 files, enchancing the musicality of the files and again adding the general benefits of Tube Processing to the overall sound.
  • Guitar, Bass and Keyboard Players. Adding the B-283 MKII to your rig is bringing big smiles to everyones' ears. Many of us have gone solid state 'digital' setups for the convenience of access to great presets and reduced weight/price. The B-283 MKII gives you most of the benefits of a tube amplifier in a simple solution. A common comment has been reduced on-stage volume wars. For keyboard players emulating real instruments be prepared to have your emulations actually sound real with the B-283 MKII. Guitarists with tube amps, get your tone at a much reduced volume, everyone will love you again. 
  • Pro-Audio/Recording. A true 'Magic Box' that can become in important part of almost ever step of your music production process. We have all had a tool we always reach for and can't live without in the studio. The B-283 is such a tool you should definitely have.
  • Computer Musicians. One obvious way to use is to connect the B-283 MKII to your Soundcard's main outputs for adding instant musicality to your digital work. Another is in your in/out loops for individual track(s) processing. My softsynth Reality is even better sounding with the B-283  MKII and Reality scored a perfect 5 out of 5 for sound quality in every review!

If you've read this far you are probably asking so whats the benefit of adding the B-283 to my system. Here are some:

  • While the jury will always be out on which is better in the audiophile world, it is always agreed that tube audio is warmer and usually more musical. Solid state was cheaper for more power for many years, but now with Grant Fidelity, tube power is much more affordable and solid state that compares to Grant Fidelity tube audio now costs much more. The cycle has reversed. But hey, we have spent good money on our solid state gear and just want to add tube warmth, natural presence and soundstage (the illusion of your speakers disappearing from your room). This is where the B-283 MKII benefits us, with solid state 'digital' equipment.
  • The B-283 MKII adds/restores natural harmonics that livens up your music.
  • The B-283 MKII adds tube warmth to digital audio.
  • The B-283 MKII reduces the work load of your amplifiers and allows them to breathe, creating the perception of more power as tube processed music's distortion at high levels is much easier on the ears.
  • The B-283 MKII makes your speakers sound much more detailed as the tube processing gives the speakers more of the music information they expect.
  • Soundstage. An audiophile term about the 'space of the music'. Width, depth and height are all increased with the B-283 MKII . 

Who the B-283 MKII isn't for:

Audiophiles with a $20k plus audio system. You have already paid good money for what the B-283 MKII will do for lesser systems. Our tests have indicated that on true audiophile systems the results are very subtle to be noticeable, which is actually a good indication of how good the B-283 MKII is. If you are an audiophile and want great tube sound, check out our Grant Fidelity tube amps.

 

Impedance Matching:

The B-283 acts as an impedance matching device, it will run between almost anything at line level and again between most pre and amps. 100k input, 100 output typical, < 500 spec. This also really helps some gear mate up up properly. Input sensitivity in minimum 500 mv, but will handle 5v output CD players fine.

Specifications: 

  • Input Sensitivity: -0.68dB (1kHz)
  • Frequency Response Range: 10Hz-100kHz (-0.1dB)
  • THD: <=0.03% (1kHz)
  • Input Impedance: 100k ohm
  • S/N Ratio: >= 60dB (A)
  • Tubes: (2) Shuguang 6N8P (equivalent 6SN7)
  • Measurement: 7" width x 6" height (including feet) x 7.5" depth
  • Weight: 3kg 
  • Fuse: for using with 220V - 0.25A/250V; for using with 110V - 0.5A/250V 

Caution:

The B-283 MKII is designed to be used Grounded, do not lift the Ground on the B-283 MKII or any of our products without running the ground to a proper ground point. Running any electrical device with the ground lifted is dangerous to both your health and equipment.

If you are planning on running the B-283 between your pre-amp and amp, when you receive your B-283, we suggest you run it first on your CD Player or another source before your pre-amp to make sure it works properly. 

Dual voltage available (110V / 220V +/- 10% ) for use in both North America and Europe. The unit is preset at factory for use with 110V. Please check the voltage before you power it on.   

 

Comments

Fri, 07/02/2010 - 16:33 — Hal Brian

MKII is a winner

This unit has breathed new life into an old system, consisting of Polk compact SDA speakers, driven by a Carver receiver.  The source is a Pioneer 7400 DVD player.  The MKII is between the DVD player and the receiver.

I am a big fan of Joni Mitchell's Miles of Aisles live album, but her voice does not sound very pleasing when she goes up high without the buffer.  With the buffer, it is lovely.  I have heard a noticeable improvement on the Leonard Cohen Live DVD too, and on several other recordings.

I only have about 30 hours on the unit, and although I purchased the Treasure tubes that go with it, haven't tried them yet.  Probably, will do that in the future with a higher end system, consisting of PS Audio DAC III (Cullen Level III Mods), into Classe CAP 101 integrated SS amp, into B&W CDM9NT floorstanding speaker.  The MKI is in that system now, and it helps tame the B&W titanium tweeter, which can be harsh, and improves the overall sound appreciably to my ears (with Mullard tubes). 

Overall, I'd say the Grant Fidelity tube buffers are very helpful and amazing value.

Thu, 08/26/2010 - 11:28 — Hal Brian

MKII Improves "High End" System

I have now had an adequate opportunity to assess the 283 MKII buffer, with the Treasure Tubes, in a system that retailed new for about $8K.  As noted before, this system has a Cullen Level III modified PS Audio Digital Link III DAC as the source, into a Classe CAP 101 Integrated amp, driving B&W CDM9NT floor standing speakers.  Undoubtedly, the buffer has made a substantial improvement in the sound stage, and the digital harshness that can be so annoying is gone. I don't possess an adequate audiophile vocabulary to describe the change, but can say that the music sounds simply more like the real thing.  I particularly enjoy classical music on this system.  The strings and other instruments simply sound more natural and sweet.  There is no fatigue and no downside to using this unit that I can discern.  Based on my experience, the unit definitely meets the goal of improving higher end systems, with no drawback.  Before using the MKII I had the MKI on this system, and that helped.  However, the MKII with the stock tubes took it up a notch, and the Treasure Tubes made it better. But, I should add that I probably did not adequately burn in the stock tubes before trying the Treasure Tubes, due to impatience, so the ones that come with the unit didn't really get a fair shake.  Overall, I think this unit is one of the best values in hi fi audio equipment, and a complete no brainer for systems lacking tubes.

Fri, 06/25/2010 - 23:28 — igrant

"I've experienced a cataclysmic improvements to my ears"

from customer Stan R. in Canada by email: 

"I received the Shuguang Treasure 'Black Bottle' CV181-Z tubes (Premium
Grade B) for my B283 MKII Tube Processor and must say what an amazing
combination! Placed in-between my preamp and amp everything sounds
fantastic. New to the audiophool scene I can't imagine a more
economical way of improving the sound quality of all my music sources.
From vinyl to digital I've experienced a cataclysmic improvement to my
ears. Thank you for your service in providing quality products AND
service in the audiophile quest.

Cheers,
Stan"

Fri, 04/23/2010 - 09:31 — boweavle

Tube Greatness!

Setup:
YBA Design YA-201
Cambridge Audio azur 640c
Dali Ikon 6
PS Audio Duet Power Center
Shunyata Research Venom Power Cables
Analysis Plus Oval One Interconnects
Analysis Plus Black Oval 12 Speaker Cables

I was very pleased with the cost to sound ratio that I had achieved with this configuration.  But as always, I wanted more if the possibility exist.  The YA-201 already sets a very pleasing sound stage... The azur is a bargain transport... The Dali's are just great all around, even compared to B&W 805S and other well praised speakers.  They are just musical!

I placed the Grant Fidelity B283 Mk II Tube processor in between the azur 640c and the YA-201.  It was magnificent from the start.  With only about 5 hours of time, the sound already reveals a deeper, wider sound stage.  Harmonicas, vocals, strings, brass, everything seems to come alive with more detail. This sense of liveliness is astounding for the price.  I feel like the concert is taking place in my listening room, or that I am sitting present in a recording studio.  My setup has now jumped several notches on the audio chain with this one inexpensive addition.  I am still looking forward to adding a tube power amplifier(Manley or McIntosh) at some point, but until then I am content.  Thanks Grant Fidelity!

Thanks,

Beau

Mon, 04/05/2010 - 18:16 — scipro

Tube Processor B-283 Mk II

My system, whilst dynamic and exciting to listen to, had a touch of the harshness that solid state systems are labelled with. I was in need of some sort of fix.

I asked the guys at Grant Fidelity about the possibility of buying a hybrid amp as I liked the dynamics and bass slam of solid state but also wanted the sweetness of tubes. They recommended a couple of choices to me but also suggested that I might find a fix by inserting a tube processor into my system. I had no idea about this tweak but for the measly sum of $190, how far wrong could I go.

I received my unit in 3 days ( I don`t know how they process and ship stuff so quickly ) and inserted it in between the CD player and pre-amp. I noticed a difference, though it was more subtle than I expected. I was a little disappointed but thought that since I had already invested in it, perhaps upgrading the stock shuguang tubes would not be a bad idea.

I researched the Shuguang Treasure tubes and purchased two CV 181 Z`s. Wow. What a mind blowing difference. The bass had slam, the top end was sweeter and the soundstage just opened up. I cannot speak more highly of the Treasure tubes and in the tube processor, it did the job for me and saved me a ton of money. Now all I need is to add a PC 1.5 power cord ( I had purchased one about a year ago for my CD player and it was phenomenal ) and see what that does.

Sincere thanks go out to Grant Fidelity.

Keith Onions

Tue, 04/06/2010 - 05:42 — igrant

Hi Keith, Thanks for the

Hi Keith,

Thanks for the comments. The MKII is supposed to be more subtle than the original B-283 as the original on well put together SS systems, typically costing more than $10k, tended to take away from some of the magic you already have, which is going in the wrong direction. The MKII is designed to for upgrading to suit your system with tube and cable rolls without taking anything away in stock form. Look forward to your comments on using the PC-1.5 on it. If possible can you list your system?

Thanks,

Ian

Tue, 04/06/2010 - 20:18 — scipro

system I am using

As an addendum to my comments about the B 283 Mk II Tube processor, this is my system

Densen B400 XS CD player
Exposure RC XXI pre-amplifier
2 Exposure Super XVIII Monoblock amplifiers
Magnepan 1.6 QR speakers
Vandersteen 2WQ subwoofer
LFD Silver Horizon interconnects
Cardas Neutral Reference speaker cables
PC 1.5 Power Cord on CD player
Audioprism Power Foundation II line conditioner
B-283 Mk II tube processor ( with Shuguang Treasure CV 181 Z tubes )

Keith Onions

Sun, 02/21/2010 - 17:46 — Grant Fidelity

"The soundstage was amazingly improved"

 

AK Member
  
Join Date: Jan 2010
Posts: 2
 
I have had the MKII almost a week now. I initially hooked it up with some cheap cables and now that my Blue Jeans cables have arrived I have been able to do some serious listening over the weekend. There is no doubt that it has opened up the soundstage and added subtle but noticable clarity and warmth to my redbook CDs. I listend to Sheryl Crow's latest CD this morning, twice back to back. The 2nd time, with the MKII fully warmed up, the soundstage was amazingly improved. It is fun to listen to redbook CDs again....one reason I bought this unit is that they sounded so bad compared to SACDs that I wasn't enjoing them anymore! BTW I have it hooked up between an HK SACD player (just the stereo outputs) and a good Yamaha receiver. Now I will see what break in time does to the unit. I initially thought I would order some NOS tubes right away but now I am going to wait and see....the results are so good now that I don't see any urgency to do any rolling.

Mon, 02/15/2010 - 19:20 — docwebb1

B283 MKII tube processor initial impressions

I am providing my initial impressions of this product which arrived today; I have been listening for several hours now.

1. It arrived promptly….about a week to get to the Los Angeles area.
2. It was packed securely; the tubes were already in the socket but it was packed in such a way there was no danger the tubes could be damaged.
3. The unit was surprisingly heavy…..really built solid. It looks very nice; I really like the look of having the tubes up front.
4. I placed it between my Harmon Kardon player and Yamaha solid state receiver (one of their better models). I turned the unit on for an hour before trying some music. I set the receiver to pure direct mode so there would be no digital processing of the incoming audio signal.
5. I listened to several CDs I had been playing the past several days both with the unit off and on. With the unit on the music had significantly more clarity and a bit more warmth and soundstage improvement. There was no loss of bass as I had feared.  Two examples of CDs I listened a lot to were Robin Trower “Bridge of Sighs” and Eva Cassady “Live at the Blue Note”.  Robin’s guitar and Eva’s voice both benefited from the tube processor.
6. Considering I hooked the unit up with cheap audio cables I had laying around, I am quite pleased with the improvement in sound.  I have ordered some good cables and it will be interesting to see what they add….as well as possible improvement from tube burn in. Even if there is no further improvement I feel I have got my moneys worth.  I also look forward to trying some tube rolling with NOS tubes….there are many options for this unit and much information is available on the internet.
Thanks Grant Fidelity!!

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