Cable Asylum: REVIEW: Dodd Audio Reference Grade Preamp Preamplifier (Tube) by ddemeterio5

Model:	Reference Grade Preamp
Category:	Preamplifier (Tube)
Suggested Retail Price:	$2600
Description:	Dodd Audio top of the line preamp
Manufacturer URL:	Dodd Audio
Model Picture:	View

Review by ddemeterio5 ( A ) on November 29, 2004 at 01:46:10
IP Address: 64.136.164.36

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It's been more than 2 years since my review of the Dodd Audio 8 watt amp. That's how long I waited for this preamp to be completed. Why so long, you might ask? Gary ran into some problems with contractors and spare parts like customized transformers and remote control to name a few. Is it worth the wait? I'll get to that later. It was a long journey for me and I discovered a few things along the way. If you don't already know, I also have Gary Dodd's popular 8 watt amp. I played around with this amp and have done a lot of tube rolling. I've gone from Sylvania 6SN7 chrome tops, RCA 5692 Red Base, CV181, Bendix 6900, 7119, 7044. The tube rolling improved the sound so much that even Gary himself redesigned the input drivers of this amp to accept 5687, 7119, 7044, 6900 tubes instead of a 6SN7. I ended up using Amperex 7119 d-getters pinched top on all tubes. I also bought the Levitator and some Aurios bearings. I have been using the Melos MA-333 for the longest time and also have done a lot of tube rolling. The Melos sound changes with the tubes you put in them. I have tried Philips 7308, Siemens CCa, Amperex 6922 d-getters, etc. The tube that did it for me was an Amperex 6922 pinched waist made in Holland. Funny how I have all Amperex pinched tubes in my system.
Now where was I? Enough rambling, let's go back to Gary's reference grade preamp. The preamp has: Dodd Audio engraved on the face plate, wood panel on both sides, a power switch, volume knob with a blue LED so that you know what the volume is from a distance or in the dark, LED for four sources (CD, tuner, aux1, aux2), one LED for mute and one for data which indicates that the unit is receiving a signal from the remote control. It has a separate chasis for the power supply and is connected to it by a customized cord with a lot of pin connectors on both sides. It has another connection for phono which leads me to believe that Gary will be building a phono preamp. The power supply has a big transformer and is so heavy that I can barely lift it. The dimensions are the same as the 8 watt amp. There are four 6SN7 tubes on the preamp and unlike the Melos they are accessible without opening the unit. One thing I notice about Gary is his obsession with allen screws and he uses them everywhere and believe it or not, even the remote control uses allen screws and you cannot change the 9 volt battery inside without opening it. Before you buy any of his products, make sure you have an allen set handy. Opening the preamp reveals the parts inside. He uses Sonicaps, Auricaps, Musicaps, Alps pot, and all silver wiring, the same silver wire that Danny of GR Research is selling. At the back of the preamp are 2 sets of pre-outs (leftmost side) and 4 sets of inputs (CD input is on the rightmost side) all of them using unbalanced (RCA) connectors.
The black remote control is all metal construction with four litte buttons on it: up, down, mute, and source. It uses a 9 volt battery and Gary says that the battery should last a long long time. He better be right, I don't find it convenient to remove 6 allen screws just to replace a battery. Warning: whatever you do, do not lose or damage this remote control because if you do, you will not be able to operate the unit. If you have a universal remote control, you can also program it to copy the 4 button functions. When you turn the preamp on it goes into mute. The remote control circuit uses relays and you could hear a click when you press a button.
The stock tubes were Electro Harmonix 6SN7 and I just pulled them out and replaced them with a Sylvania 6SN7 black base chrome top in short bottle. I had these tubes for a while and they have acceptance dates of 6/45. When the preamp arrived, I still had the Melos and listened to it for comparison. How does the reference preamp compare against the Melos? In my opinion it bettered the Melos in many areas: macro and micro dynamics, bottom end, mids and highs, soundstage, focus and imaging, and transparency. My listening test begins with Patricia Barber, Ode to Billy Joe the bass riffs just sounds fuller and the finger snap is more flesh sounding. Moving on to the next track, Too Rich for my Blood there is a bass solo on it and the bass is played fast, here the reference preamp played every note with authority and each note distinct from each other. I also use the track Use Me on her Companion album and the bass solo in the introduction was rendered with amazing speed and articulation. I also listened to Bach Brandenburg Concertos, Christopher Hogwood track 9 Concerto No. 3 in G Major-III Allegro same here: the violins, viola, cellos were played super fast and the reference preamp just handles it with ease and on top of this the harpsichord was reproduced without skipping a note. To test the highs, I used Patricia Barber, Too Rich for my Blood where you will hear different sounds of cymbals, crash, rides, etc. and it rotates in the soundstage. Here the decay was better and cymbals sounds so distinct from each other and it made me dizzy just following the rotating cymbals. I also listen to Nardis where there is a part in the track where the drums and percussion duel it out and suddenly stops followed by cymbals. The reference preamp reproduce all of this without a hitch. How do the midrange sound? They sound crystal clear. I listen to Cassandra Wilson, You Gotta Move her voice was not too chest sounding as I sometimes notice in the Melos. In the reference preamp I could even hear her do that Michael Jackson uh-uh thing. Listening to Diana Krall's piano solo on Boulevard of Broken Dreams, the attack and speed was spot on and the piano sounds like a percussion instrument rather than warm sounding. In Bach's Brandenburg Concerto No. 6, Concerto for 2 Harpsichords in C minor the harpsichords are not thin sounding, there's certainly more body to it and I hear more strings being struck. In Rimsy-Korsakov Scheherazade, Serebrier track 2 the tale of the kalender prince you hear two violins talking back to each other, The violin playing a higher note sounds sweet and not screaming at you. Speaking of transparency, this preamp has surprised me a lot more than the Melos. Case in point:Holly Cole, Temptation I could hear two other voices from the left and the right, the left singing the higher voice and the right singing the lower voice and of course Holly in the middle. Train Song is arranged with so many sounds in it, in the beginning of the track I could hear what sounds like wind blowing in and out at the back of the soundstage. In Janis Ian's Guess You'll Have to be There, I noticed that the guitar riff at the beginning is played with echo/repeat effects and I didn't notice this with the Melos. The same with Bela Flecktone's Cosmic Hippo, I could hear squeaks from finger movements in the string in the Synth Axe Drumitar. To test soundstage, focus, imaging I like to listen to Bobby McFerrin's Don't Worry Be Happy, here the reference preamp passed in flying colors. In the track Drive I could hear the voice that simulates the car moving from left to right and right to left of the stage. The movement of this voice was easier to follow in the reference preamp than in the Melos. I also use Beethoven Symphony No. 5 in C minor, Allegro con Brio by Carlos Kleiber to test soundstage depth. The reference preamp passed this test and the different sections at the back of the stage can be heard clearly and the movement of sound from one section to the other.
Now that I have said what's good about this preamp, let me mention the not so good things about this reference grade preamp. First of all, I don't think that muting the preamp when you power it on is a good idea because that means you can not listen to this preamp if you lose the remote control. Second, the stock tubes are not good enough for me and I know it's hard to find a steady supply of good 6SN7 tubes but using subpar tubes will make some people judge the quality of this preamp on the performance of the stock tubes and that does not do justice to this remarkable preamp. There are no balanced outputs on this preamp. In the future, I hope servo will replace the relay in the remote control circuit. The clicks can be annoying to some people.
To sum it all up, I am impressed with the improvements of this preamp over the Melos preamp. I bet you this amp will trash many preamps out there that costs a lot more. Though many people starting out in high-end audio will not spend $2600 for a preamp, they will eventually move on to something better in the future and in my opinion this is more than something better. It is without a doubt a reference level preamp and I will be keeping this unit for a long long time and who knows maybe this is it for me.

Product Weakness: no balanced outputs, not so good stock tubes
Product Strengths: dynamics, articulate lows with authority, transparency, deep soundstage, excellent highs and mids

Associated Equipment for this Review:
Amplifier:	Dodd Audio 8 watt amp
Preamplifier (or None if Integrated):	Melos MA-333
Sources (CDP/Turntable):	Heart CD 6000
Speakers:	GR Research Paradox 3
Cables/Interconnects:	LAT International, Silver Audio
Music Used (Genre/Selections):	Blues, Jazz, Rock, Classical, Vocals, Pop
Room Size (LxWxH):	19' x 24' x 13'
Room Comments/Treatments:	ASC Tube Traps
Time Period/Length of Audition:	1 month
Other (Power Conditioner etc.):	Monster HTS-3500
Type of Audition/Review:	Product Owner

Product Weakness:	no balanced outputs, not so good stock tubes
Product Strengths:	dynamics, articulate lows with authority, transparency, deep soundstage, excellent highs and mids