Battery Powered Preamps

I notice that the more expensive preamps get within a line, or in general, the more complexity and expense seems ot be applied to the power supply and regualtion; sometimes with the addition of a second box for the power supply.

I conclude power supply is important. If this is so, why not go the simpler route of battery power for pure DC? My Dodd Battery Pre works very well indeed (for context -I've owned CAT, Lamm, ARC, Joule, Placette Active, Atma-sphere (still own), Bent TAP). Am I missing something, or doesn't battery power just make the most sense for a preamp - off the grid and all that? Seem much simpler than most highend approaches, and much less expensive to implement.
In my opinion, you are right on. I'm headed to the Rocky Mountain Audio Festival this week-end specifically to listen to the Red Wine Audio SLA battery components. Aside from the Signature amps, they've just released the Isabella preamp - which includes a battery powered DAC (the other component super sensitive to power current issues).

I've been thinking of getting a Sutherland as my phono stage anyway, so if I like what I hear in the Red Wine components, I'll have a lot of expensive power cords and power conditioning to sell. ;)
Yep, I agree. I have been experimenting with battery power as of late, with great success. In addition to the Dodd (which is marvelous), I also have a Musical Surroundings Nova Phenomena phono stage that is also battery powered. It seems that few would argue that clean AC is one of the biggest hurdles to achieving top quality sound. It makes sense to me to avoid the issue altogether whenever possible.
It would be interesting to hear from some designers on the issue, like Ralph Karsten of Atma-sphere and others. Since I know nothing at all about electronics I may be blind to something critical that makes getting on the grid worth the effort. But I do wonder why so much money and expense in preamplfiers center around the power supply, in some lines (e.g. First Sound)the difference in cost, sometimes significant, is almost exclusively centered around the power supply. If the "grid" is such a problem, that needs so much engineering - why not avoid it in the first place -- other than the fact that you have to recharge the batteries evey 6-12 hours (not a problem for me)? Id rather have improved S/N, no power cord issues, no conditioning required. Seems like an elegant solution; and I can attest that the Dodd sounds darn good. I also notice that the BAM on my Merlin Speakers sound better in battery mode than AC mode.
IME batteries sound fantasic powering noise-sensitive CDP, transport, DAC, and other line-level SS & op amp devices. Batteries work really well with low-current applications, but are infeasible in all but the most minimalistic of tube designs. However, not all batteries are strong in the area of dynamics & bass control. Large SLA batteries with lots of filtering capacitance perform well in this regard, but are impractical for most manufacturers due to weight and ROHS lead issues. Other battery types are compromised to one degree or another.
Dgarretson, do you know if the Dodd is a minimalist tube design? It seems to work well on batteries (4 12volt 5 amp SLA batteries - pretty heavy). Not as strong in the bass as the CAT Sl1 but it does seem very balanced. I wonder if Gary Dodd has overcome the inherent problems you describe through good circuit design or not. On my Merlins which only go to 28hz, the bass seems very good and dynamics seem very strong as well (not to the level of the CAT perhaps which is the most dynamic preamp I have heard)but pretty darn good.
In my opinion, you are right on. I'm headed to the Rocky Mountain Audio Festival this week-end specifically to listen to the Red Wine Audio SLA battery components. Aside from the Signature amps, they've just released the Isabella preamp - which includes a battery powered DAC (the other component super sensitive to power current issues).

I've been thinking of getting a Sutherland as my phono stage anyway, so if I like what I hear in the Red Wine components, I'll have a lot of expensive power cords and power conditioning to sell. ;)

While in the RWA room, do not pass on the opportunity to listen to Vinnie' new phono stage.
Here are some information forwarded by Vinnie:

- MC / MM input with HI/LOW gain settings
- Adjustable standard load settings, plus a "custom" position for a custom installed load resistor
- Discrete, class-A, zero-feedback gain stage (similar to what we use for the Isabellina dac's output stage), followed by the same tubed output stage as the Isabella (1 pair of 6922/6DJ8s).
- SLA battery operation with SMART module and rapid charger
- Similar enclosure as the Isabella, with sliding glass window on top for easy tube rolling.

I do believe that
*lowering the floor noise
*eliminating any associated problems with power lines
*having the key components of the grid (phono,preamp,dac or cdp)
- are all important, beneficial and ....IMO and experience, sound excellent.

RWA Isabella with DAC is great.
Without trying to sound like a salesperson let me just say that Dodd as well as Isabella/Isabellina dac are one of the easiest recommendations. In fact, I am not aware of a single soul who regrat buying any of the above mentioned preamps.
My next purchase is guessed it - RWA phono (however, I'm not counting out Dodd's phono yet).
I should have it in my home by the end of the year as a part of another shoot out. This time it is all about analog.

Three modified turntables (DIY Red Devil, MMF7 in bamboo double plinth and Lenco l75 replinthed and tweaked)two to three amps (Consonance modified Cyber 800, Melody 300b monos or I2A3 integrated, possibly Manley Stingray integrated, two single driver speakers based on Fostex drivers, carts, arms and phonos line-up will be announced before the actual event.

Should be fan.

While I'm not an engineer, i believe you can call the Dodd a minimalist tube design in that it only employees two 6922 variety tubes and, in fact, only one of the twin triodes in each tube is employed at a time. In other words, you could burn the tubes for say 10,000 hours and then swap their positions and go another 10,000 hours. Certainly, this is a cool benefit given the cost of NOS tubes. (Please don't ask me how this works, I'm just referencing what I've read in reviews :).
I don't know enough to fully understand Dgarretson's technical explanation, nor whether Gary Dodd might answer "yes, generally true, but...." I do know the Dodd seems to be a pretty effective implementation of battery power and a whole lot simpler than complex power regulation and power supply I've seen in some of the preamps I've owned before. Since there haven't been many battery powered preamps before, I suspect that either battery technology has improved, or new thinking has found a way to deal with some of the issues Dgarretson raised. If that is the case, it would seem battery power holds a lot of promise compared with our traditonal way of designing preamps.
I have not heard Dodd, and am not suggesting that a minimalistic design can't sound great. Only that battery power restricts the designer in terms of number of tubes and type of tube used.

BBAM has only several active devices inside(low current op amps) which sound good on stock NiMH batteries, but much better on large SLA, both in terms of supple grainlessness across treble & mid and more dynamic scale and bass authority, owing to lower internal resistance and lower noise of SLA. Generally speaking the larger the SLA, the lower its impedance. In this case size matters in terms of transient response, independent of amp-hour capacity.

With lesser battery setups in my system I've heard a detailed & smooth treble & quiet black background, but pale/soft dynamic contrasts and lack of ultimate slam. If this is characteristic of Dodd, it could likely be improved with additional filtering capacitance and/or larger/faster batteries. Anybody at RMAF, please check out the new Roland battery pre and report as to whether strong or weak on these points. The Roland uses std D cell batteries.
I believe that a battery power supply done to the highest standards would be quite expensive in the marketplace.

A friend of mine incorporates heavy duty, fully-regulated rechargeable dual mono DC power supplies to power the preamp he manufactures and the DAC side of his cd player mods. (The batteries in the power supplies are hooked up to the A/C when the system is not in use, and then disconnected to play music.) I believe the batteries are 9 or 12 volts.

For best results, you need a separate power supply for each component. He sells these power supplies to friends for $1400 apiece. I can just imagine what the cost would be if both he and a dealer had to make a market profit on them. Moreover, the batteries are quite heavy.

I don't understand the electronics, so I can't explain what is involved in building the power supplies, or why they are so expensive. But I am sure there are good engineering reasons why a power supply containing regular batteries would not measure up.
I use a Battery powered TRL custom pre-amp. It is a very low gain design which suits my system very well and the sound is amazing.
I have owned many high-end tube and SS designs.
I have not owned one but have heard one extensively and the Reflection Audio OLM -1 battery pwered preamp is fantastic.
So yes, I think when well implemented and synergisitc with other components this is a great way to go.
The Dodd uses (2) 6dj8s and as previously mentioned, it only uses 1/2 of each tube (when they get old you switch tubes and the other half of the tube is used). I thought this was a pretty nifty feature for getting double the life from expensive NOS tubes, but maybe part of the decision was based on the battery supplies limitations in terms of driving tubes - don't know. Maybe a well implemented battery power supply is expensive, but nothing like the $10,000K + traditional preamps with robust powersupplies, often requiring a second chassis.
The RWA Isabella is an amazing tube preamp and runs completely on SLA battery power. I own it, along with the Signature 30.2 and the off the grid experience using these SLA batteries has very clear advantages to my ears.

6moons just released the review of the RWA Isabella. IMHO this review is spot on!

Now I am playing with tube rolling using Amperex 7308s. Wow they are very sweet!!!

The first battery powered preamp, the Mission 776, used two 12 volt lead-acid in series. Those type of batteries are still used in emergency lighting and are not expensive. Dynamics was not an issue. I only had to replace the batteries once in 6 years. Much of the cost is in a reliable, automatic charging system. On the other hand, the batteries in laptop computers can be very expensive to replace.

Tubes require high voltage which means many batteries, probably smaller, in series.
The only reasons that drove me into buying Dodd and then Isabella/isabellina preamp/dac were,
*my annoyance with filthy power
*lowering the floor noise
*overall sound quality - it simply sounds phenomenal
*innovative, yet simple approach - my kind of guys.

At the end it comes down to the most essential question:
- is the use of batteries beneficial to the overall sound quality and enjoyment? know what my answer is. How about you?



The money generated from the sells of all power cables and conditioners, paid for the Isabellina dac option. Totally worth it. Upgrade that I can actually hear and appreciate.

Assuming battery implementations overcome what might be a theoretical issue regarding bass and dynamics (owners of Dodd and RWA seem to think this is not a problem with their preamps)wouldn't battery DC be cleaner and more "perfect" than what complex power supplies and regulation could possibly accomplish? It just seems a lot can wrong in the AC to DC conversion (let alone power cords, and quality of AC in most homes) and delivery versus pure battery power. I ask as an electrical neophyte, but it just seems that simpler is generally better.
Dgarretson, JRDG twin chassis Criterion is based on BB OPA1632 modules. Jeff Rowland designed its battery PS around NiMH D cells. I will finally listen to it in room 505 on Friday at RMAF. . . still have no idea if it sounds good, bad, or indifferent. I am also curious to find out how it compares to the minimalistic SS PS Capri, which is also based on BB OPA-1632. I will definitely also visit RedWine and Dod suites.
Dodd batttery pre and ASR Exclusive battery phono are keepers for me.
Guido, I don't know if Reference Audio Mods is at the show, but if so, consider stopping by to hear an all battery-powered system that Kyle of RAM & Serge of Audio Consulting in Switzerland have been developing for some time. Like Rowland, they are also doing some impressive things with the latest generation of op amps and batteries.
Dgarretson, are you thinking battery power frontend electronics, I'm concerned with preamps in particular, is where we are heading for best sound?
Dgarretson, I just searched the official RMAF Excel spreadsheet, and I cant find RAM nor Audio Consulting. If you or any one else finds them lurking somewhere at the show, post here and I will definitely visit them.
For anyone attending the RMAF this weekend, be sure to have a listen to the Veloce Audio LS1 battery powered TUBE linestage. Those that have had the opportunity to do so already have been stunned by the performance of this completely new design. Also showing with the battery powered monoblock amplifiers and Kharma speakers, so it should be very, very good.
Pubul57, in low-current source and LS components the new SS monolithic op amps and buffers are particularly good, and if powered correctly may even surpass tubes in terms of transparency & musicality. However, IME op amps don't get to this high level of performance without batteries, whereas tubes can sound great both on AC regulated power or on batteries. The gating factor is finding tube designs that operate within the limited current reserves of batteries.

Another advantage is that monolithic op amps *should* reduce complexity and costs-- though this does not appear to be true of the $18K Rowland pre.

Anyway, my gut is that op amps on batteries aspire to SOTA, whereas(as noted in the 6moons review of RWA Isabella) a tubed pre on batteries is more about high performance in the context of value.

BTW, what I've found is that though an unregulated SLA battery supply can surpass a more complex AC PS, the battery sounds better yet with gobs of capacitance and discrete DC voltage regulation circuits. These features are not inexpensive to implement.
Dgarretson, would love to get your impression of the Dodd. SBank also owns Merlins (great minds...) and switched to the Dodd after owning the Atma Pre (he had the MP-3, not the MP-1). In my system I prefer the Atma-Atma combo, but I prefer the Dodd with my Music Reference. I don't understand the theory, but I think Gary Dodd knew what he was up against and obviously came up with a pretty good approach. I wonder if this is Gary's all out approach to a batttery implementation at $3,300, or if more money could have done even better (he didn't spare any expense on the wood chassis or top plate) - there are not a whole lot of parts in there, but maybe as many as necessary and no more. I'm looking forward to RMAF, there seems to be a lot of ingenuity going on out there.