[krmathis]

A week or so back I received my Signature 30.2, and fell in love immediately.
For those who don't know the Signature 30.2 it is a battery powered amplifier, made by Red Wine Audio (hereby referred to as RWA). The same company that make the well known iMod.

The Signature 30.2 seems to be quite rare among Head-Fi'ers though, and I thought it would be nice to make a dedicated thread.
For owners to check in (say Hi!

), user impressions and for general discussion about the amplifier.

Links:
Vendor -> Red Wine Audio - Signature 30.2
Articles -> 6moons - Signature 30.2 / TheStreet - A Stereo Amp That Packs a Punch / StereoTimes - Off The Grid. Way Off / Tone Audio (issue #14)

 

[krmathis]

Pictures...

 

[krmathis]

Intro:
I bought an AKG K1000 some weeks back, after having had my eyes on it for a long time.
After hooking the K1000 up to my Doxa 70 Signature MKII (norwegian made 2x70 watt speaker amplifier) I found out that it sure had a lot of potential, but that the Doxa was not the ideal match. Remembering that I also had been on the lookout for something different to drive my Stax headphones, I decided to find one amplifier that could be used for both tasks... I looked into several alternatives (Air Tight ATM-300, Lyngdorf TDAI2200, WooAudio WA5, ...), but after some consideration I landed on the Signature 30.2.

I found a demo used Signature 30.2, which arrived at my place a couple of weeks back.
Hooked it straight up to the Electrocompaniet ECD1 in one end and the AKG K1000 in the other end, and after just a couple of tracks I were quite sure I have found the amplifier for the K1000. I have so far just found time for a really short listening session with the Signature 30.2 driving the SR-007BL through an SRD-7 Pro, but no speakers.
For more details, scroll down to the Impressions: part below.


About the Signature 30.2:
The Signature 30.2 is an SLA (Sealed Lead-Acid) battery powered Tripath-based amplifier, putting out 2x30 watt. A minimalist well built amplifier, using top quality parts and with short signal paths. Its quite small in size, measuring just 32cm (width) x 23cm (depth) x 9cm (height), but weighing in at a solid 7kg.

Its battery powered design mean that it will be off-grid during playback, isolating it from the mains. With the benefits of less background noise, portability, and more. A full charge take about 2 hours, and will last for 12-24 hours. Depending on load and sound volume. Its external charger accept any voltage between 100v and 240v. The charger should stay connected all the time, ready to charge whenever you turn the amplifier off.

On the back side it have one set of unbalanced inputs (RCA), a pair of unbalanced (RCA) outputs, an XLR connector for the charger, and speakers bindings that accept speaker cables terminated with forks or banana plugs. While on the front side it have a touch sensitive On/Off switch, a volume knob (24 step Goldpoint) and a receiver for the remote control (volume Up/Down). That's it.
It can even be bought as a power amplifier, without the volume knob and remote control.


Impressions:
First I want to let you all know that I have next to none experience with the K1000 in combination with other amplifiers. So take that into consideration when reading my impressions.

Hooked the Signature 30.2 to the Electrocompaniet ECD1 as input and the AKG K1000 as input. Then I sat down, and carefully placed the K1000 on my head. Slid my finger gently across the power button to activate the 30.2 and heard a little 'click' as the amplifier turned on. Put on some of my favorite tracks as started listening.

The first thoughts/words that ran through my head were "control", "space", "sound stage"...
It seems to have a lot of power, holding the K1000 under strict control. Producing low frequency bass and punch that I did not even know the K1000 were able to put out. I also noticed that it has a low noise floor, no noticeable hiss. Just a black background.
The mid range is warm, magic, and pulls you right in. A really nice match for female voices. While the top end can be described as open, airy and extended. It seems to have a quite large sound stage (width, depth, height), which stays sharp.
In my eyes a really nice match for the K1000.

As mentioned I have had a small listening session with the Signature 30.2 driving my Stax SR-007BL, with the help of an SRD-7 Pro.
The result were really promising. The 30.2 held the SR-007BL under tighter control than my SRM-007t. And compared to some of the other speaker amplifiers I have tried it were even able to make the SR-007BL shine in the top end. It still feels somewhat limited by the SRD-7 Pro though.


That said, the 30.2 may not be for everyone.
Its not a power beast, and you need to put some though into what you hook it up to. Speaker sensitivity being the most important part. After all its a limitation what you are able to drive with "just" 30 watt.

This one is certainly a keeper!

 

[aaron313]

Holy crap, krmathis started a thread!

 

[tyrion]

I spent a little time with the 30.2 at CanJam. Unfortunately, it was in the main room which was not conducive to K1000 listening. Having said that, I really enjoyed the amp. I love the nice clean look of Vinnie's gear and enjoyed my Sig 30 for a while. In the end, for my speaker rig, I moved in a different direction. I would love to hear the 70 watt mono blocks one day.

krmathis, next step is to get a pair of Omega SuperHemps for the Sig.

 

[BigEat]

How does it work? What kind of batteries? What do you like about it best? etc. etc. Yes, I know I can go to the website for all the technical crap, but I want someone to tell me about it.

 

[jp11801]

SLA batteries that last a long time if you take care of them.

The Sig 30 was excellent and one of the best D class amps I have heard. Has the advantage of transportability and compact form with no heat issues. Lacks leading edge note definition as well an finer details. It was the polar opposite to the First Watt F!. While I know my experience was with the Sig 30 not the 30.2 they should share similar traits. That said it is an excellent amp particularly if you like a more relaxed presentation and typically have long listening sessions. The icing on the cake is Vinnie is one of the best guys out there in the audio world.

 

[krmathis]

Quote:

Originally Posted by aaron313 /img/forum/go_quote.gif Holy crap, krmathis started a thread!

Yeah, I should do it more often.

Apart from when I buy/sell stuff that is...

Quote:

Originally Posted by tyrion /img/forum/go_quote.gif krmathis, next step is to get a pair of Omega SuperHemps for the Sig.

Not all into speakers. But we will see what happens...

Quote:

Originally Posted by BigEat /img/forum/go_quote.gif How does it work? What kind of batteries? What do you like about it best? etc. etc. Yes, I know I can go to the website for all the technical crap, but I want someone to tell me about it.

It works really well.
Just make sure the batteries are charged (they charge when the amplifier are turned off). It uses two 12v SLA batteries (Sealed Lead-Acid).

What I like about it (random order):
* Sound quality.
* Hand built using high quality parts.
* Battery powered, and hence quite portable.
* Minimalist design.
* Customer support. Vinnie (vendor) are a really friendly guy.

Quote:

Originally Posted by jp11801 /img/forum/go_quote.gif The Sig 30 was excellent and one of the best D class amps I have heard. Has the advantage of transportability and compact form with no heat issues. Lacks leading edge note definition as well an finer details.

I don't know the Signature 30. But know that there have been lots of changes between the 30 and 30.2.
So far it has not struck me that the 30.2 lack finer details and/or note definition. But I have only had about 30 hours on it. Meaning that neither it or me are fully adapter/burned in yet...

 

[n_maher]

Great thread krmathis. I hope others will use it as an example of a productive way to share thoughts and impressions about gear.

 

[krmathis]

^ Thanks!
I don't write as long and detailed reviews as others around here, but feel I got the most important points down.

 

[progo]

The Ideal portable rig?

Looks certainly a babe!

 

[krmathis]

Quote:

Originally Posted by progo /img/forum/go_quote.gif The Ideal portable rig?

iMod -> Signature 30.2 -> K1000 would have been a killer "portable" rig.
Would get a lot of attention in public places though.

 

[Skylab]

Nice review krmathis! After reading this, I am now even more interested in the Isabella battery powered tube preamp/headphone amp

 

[stevenkelby]

Quote:

Originally Posted by krmathis /img/forum/go_quote.gif iMod -> Signature 30.2 -> K1000 would have been a killer "portable" rig.

Just saw this thread and that's how I use mine! Transport it to and from work anyway. V-caps and Pico are in there too. Pico just because I haven't made a cable to bypass it yet. Also use USB from PCs sometimes at work with other peoples tunes. It's a good job sometimes.

Use the 30.2 at home for Superhemps and dual Deephemps too.

I really love this amp, got one of the first and it never fails to impress, I take it around in a case in my bag to audition equipment and to mates houses. If I ever run away from home the 30.2 will be in my bag! Vinnie's my hero too.

Only had the K1000 for a few days, most of the bottom octave really is missing but they are better than expected elsewhere. I love them but they don't sound quite as good with other ammps I tried, a Rotel, a Yamaha and a sonic impact. Demo's with some binaural recordings blow anyone away, even people who don't care for audio. The Cerini Holophonic one is hilarious to watch, ever single person has looked around themselves! Gotta find more like that.

the upshot is, the system does the same thing with real music too, so many instruments truly sound 3d and believable for the first time. All the little spacial cues of the instrument and recording space are suddenly right there and audible. Bad recordings don't sound crap either. I get the same effect with the Omega Hemps too actually, maybe the 30.2 is magical...

 

[krmathis]

@Skylab. Thanks!
The Isabella sure looks nice, and have received a couple of positive reviews. Its looks like a strong candidate for those looking for a top quality pre-amp.
Since I only use one source and already have the integrated Signature 30.2 I have my eyes on the Isabellina instead (standalone version of the DAC optionally built into the Isabella). The Isabella will be too much overkill for my use.

@stevenkelby. That sound great.
To use the Signature 30.2 in a "portable" rig is currently beyond my wildest dreams. But I appreciate the ability to just put it in the backpack and easily bring it with me for a listening session outside my home (friends, Head-Fi meetings, etc.).