[jrebman]

It's full name is the Antique Sound Labs MG Head SE OTL Mk. III -- only a true marketing genius could have come up with such a name.  Despite the awkward name, this is one hell of a nice tube amp at a very reasonable price.

A couple things that drew me to it in the first place:

1). it uses el84 output tubes, which are one of my very favorite sounding tubes, and are plentiful and relatively inexpensive, and with several good to excellent current production brands available at reasonable prices.

2). It has been said by many on head-fi that it has wonderful synergy with the Sennheiser HD-650s, which I also love and now, except for a pair of Sennheiser PX-100s are the only cans I own

3). It is a 2 chassis design with the power supply in a separate box and an umbilical connecting it to the main amp unit.

4). It may be the only amp out there that lets you choose between transformer coupled output or OTL simply by flipping a switch.  I pretty much use OTL exclusively but if you had lower impedance cans, you'd likely have to use the transformer coupled output.

A couple of other nice features are that neither the power supply or main amp gets hot -- just warm.  It has a tube cage, which is very useful considering it sits on my nightstand and I really don't want to roll over in the middle of the night and have my hand grab a hot tube, nor do I want any bed linens accidentally landing on them and catching fire.  And miracle of miracles, there are two headphone jacks so you can share the music.

Back to the tubes... the el84s seem to barely get warm as you can put your hand directly on the chrome plated heavy wire cage and barely feel any heat.  Likewise, the 12ax7 driver tube is about the same, so my guess is that they are both being run fairly conservatively and therefore, I'm expecting tube life will be quite long.

One minor disadvantage of OTL mode is a slightly higher background noise, but I'm suspecting that a little power line cleanup (maybe a nice homemade PC with a felix in it is will be the ticket) and switching to a 5751 driver tube should take care of 90% of that.  I don't want to overemphasize this as it doesn't bother me at all, and I'm really sensitive to hum in my audio systems, and this doesn't bother me in the least just as it is.

The main amp is about 7" x 8" or so, and about 6" tall and is a very hefty chunk of metal with a nice, smooth finish.  The back panel has two sets of RCA jacks -- one is a passthrough to your main preamp or amp, and the multi-pin connector for the umbilical.  The power supply unit is approximately half the size and only about 3" tall.  The front panel has a rocker switch of decent quality and I assume some sort of LED indicator.  The back has the IEC AC inlet and the captive umbilical (always nice to eliminate a connector whenever you can.)  Again, construction is solid with a nice finish.  These are both hefty little chunks of metal, and the metal sheet seems to be quite thick, with even thicker front panels.  Other mscellaneous physical considerations -- all switches have a nice positive feel, the volume knob, although fairly sensitive with the 12ax7 driver, feels smooth tight, and the jacks all appear to be of very good quality.

Now for the best part -- the sound.  What can I say here except that the folks on head-fi who said this amp has fantastic synergy with the HD-650s were right on the mark.  When I first got it it was a bit sluggish and thick but after about 10 hours of playtime it began to open up with a more lively presentation, better extension, and dynamics.  Now, about every week or so I notice another incremental improvement, and then when I recabled the 650s, things really began to happen.  All the magic of el84s is here and this is not a bloated overly tubey amp, but does retain enough of that tube sound to be obvious, yet not overwhelming.  Detail retrieval is great, dynamics are very good (and still seem to be improving) and overall, I have to say this is by far the nicest headamp I've listened to, especially with the 650s, which just seem to want a good tube amp.

Mind you, all of this is still with the stock tubes, and I really have no idea what those are.  I've got a pretty extensive collection of el84s of all kinds from rare and exotic NOS, to some of the better current production varieties -- TAD, Genalex.  I also have a couple of red label RCA black plate, double mica 5751s, and a prize NOS 1950s triple mica, black plate Sylvania 5751, as well as a few other 5751s and some nice 12ax7s, so I suspect there is more goodness in store when I feel the amp, cable and phones are ready enough.

I didn't mention it, but my source is a NOS Sony D25S walkman, which is anything but your typical walkman.  Sometime in the next week or so I'll be using a USB dac of some sort -- probably my Audio Sector.

List price on this amp is $500, but I got mine for $425 from Galen Carol Audio in San Antonio, TX.

Highly recommended for the hd-650 fans out there.

-- Jim

[BradJudy]

Here's a link to the ASL US distributor's page with specs and pictures - http://www.divertech.com/aslmgheaddt.html

ASL's main webpage is one of the worst I've seen in years, so I won't subject anyone to it. 

[jrebman]

Thanks, Brad,  Knew I forgot something .

-- Jim

[ecramer]

Thanks for posting the review. Do you know what the difference between the SE and the DT model are?. From the list of tubes in your stash you will be busy tube rolling

[jrebman]

Ed,

Actually, I have the DT model.  That's what they get for such a screwy naming convention.  There is one higher model which is designed primarly as a preamp with remote volume controol, but the headamp section of that is optimized for AKG 1-000s -- so much more powerful.  There is also another model one step below the Mk. III which sells for $300 and has the same tube complement as the Mk. III, but that's about all I know about it.

As for tube rolling, once I hit upon the combination I like, I'm pretty much just going to leave it alone.  At some point I may also peek under the hood and see if a new coupling cap may be worthwhile, and I'll probably put a switch on the back panel and have it switch between the two sets of RCA inputs as I won't be using the pass-through.

This amp will eventually be relocated to my office when my s.e.x. amp goes in the bedroom as that will serve double duty as a headamp and to power some small speakers.

-- Jim

[jrebman]

Finally, a little tube rolling to report on.  I now have a pair of the new GEC Gold Lion N709/EL84s and a NOS 1957 sylvania triple mica 5751 in the amp and think I'll be leaving this combination in for a long time.

Yes, the 5751 did indeed lower the noise floor even further and I have still not tried anything but the stock power cord directly into a standard wall outlet.  I'm also still using mostly the Sony D-25s discman and a rather unremarkable StraightWire 3.5mm stereo to RCA cable.

At first the new tubes sounded about the same as the old ones (except for the lower noise floor in OTL mode) but even during the first CD, the bass began to tighten up, the highs extended much further and details came out of the woodwork that I had no idea were on these CDs.  The tubes are still relatively new but they really seem to improve with every CD played through them., and all I can say is wow, never thought the 650s could sound like this.  I liked them enough to begin with, but the cable upgrade was a noticeable improvement, and now with this round of tube rolling, it seems like there's little more I could want for.

As for what they replaced, I have no idea as there were no markings whatsoever on the stock tubes -- 3 very clear pieces of glass.  Whatever they were, they weren't too terribly bad, but they just can't even begin to compare with the new GECs and the NOS 5751.

I'm in the process of building an AMB.org Gamma DAC, so when that's done that will be the main source and I'm expecting good things still to come.

Still a very recommended amp for Sennheiser owners.

-- Jim

[dhwilkin]

Man, it's been a long time since I've visited Head-fi. Interesting to read about this amp, I had one of the original MG Head amps way back when, ended up replacing it with a Headroom Max. That MG Head amp was a decent performer for the price as I recall, but man that line was plagued was build quality issues (my unit included). What is the consensus on ASL's build quality on this version of the MG Head?

[ecramer]

The noise from tubes always has me a little aprehensive of trying a tube headphone amp. although i have lusted after one of the darkvoice amps.

ED