FS: Mapletree Line 3A SE preamplifier

rajacat · « **on:** 7 Mar 2009, 10:17 pm »

~~$525~~ $475 shipped CONUS. obo

This unit has a third summed channel which can be used for a subwoofer, center channel speaker or both. It also Includes 2 complete sets of tubes, powercord and power supply umbilical cord.

I have performed two simple mods that have noticeably improved the sound quality. The Auricap 1uf output caps have been bypassed with .01 T-1 Russian teflons. I replaced the Alps Blue attenuator with a smd stepped unit. I will include the removed Alps unit.

There are some scratches which are visible in the photos. Some of the faceplate lettering and insignia plate logo
on the power supply has faded away due to the heat.

Functionally it works perfectly. I will ship it double boxed and packed very securely.

http://picasaweb.google.com/rajacat97/Audio3?authkey=Gv1sRgCI_D5dPespWhjQE#5310557942061251026[/img]

http://hollowstate.netfirms.com/

-Roy

rajacat · « **Reply #1 on:** 8 Mar 2009, 06:38 pm »

Sunday bumpday.

rajacat · « **Reply #2 on:** 9 Mar 2009, 07:46 pm »

Unruly highs and digititus?

. This pre will tame them.

-Roy

rajacat · « **Reply #3 on:** 10 Mar 2009, 05:14 pm »

rajacat · « **Reply #4 on:** 11 Mar 2009, 03:55 pm »

Reduced!

roscoeiii · « **Reply #5 on:** 11 Mar 2009, 11:23 pm »

Was this a kit build or built at Mapletree?

rajacat · « **Reply #6 on:** 11 Mar 2009, 11:39 pm »

It was built at Mapletree. I'm not the original owner. I was told that it was a custom unit with the extra summed channel hence it's 3A instead of 2A. I suspect that Dr. Lloyd, the owner of Mapletree Audio, would remember it so you could give him a phone call.

BTW it has a switch of the back so that you can use 6SN7's as well 12SN7 and 12SX7.

-Roy

ps... I could post a photo of the bottom with the serial number

OK, Go back to my gallery and the serial # photo is there.

http://picasaweb.google.com/rajacat97/Audio3?authkey=Gv1sRgCI_D5dPespWhjQE#5312084209083885890

satfrat · « **Reply #7 on:** 11 Mar 2009, 11:48 pm »

roscoeiii · « **Reply #8 on:** 11 Mar 2009, 11:57 pm »

And do you know when it was originally built? Looks fairly old, but that may just be the retro style that's all the craze these days...

rajacat · « **Reply #9 on:** 12 Mar 2009, 12:19 am »

I bought it in 2006 from another AC member, acresm22. He said that it was almost new. Actually the unit was built with the SE upgrades which include some Blackgate caps. The older 2A's didn't have the Blackgate upgrade available. The retro look is exactly same look that you would get if you ordered a new unit. I like the no frills functionality. BTW this preamp doesn't tubey at all. Sounds very linear to me but, like I said, it excels at taming unruly highs and digital hash. It's easy to work on and you don't need an EE or the hands of a brain surgeon to repair or mod it.

-Roy

Bigfish · « **Reply #10 on:** 12 Mar 2009, 12:55 am »

Guys:

If you are looking for an excellent sounding preamp please do not be pass this up because of the no frills looks and relatively low price. This preamp is all about performance and is a giant killer!

Ken

rajacat · « **Reply #11 on:** 12 Mar 2009, 05:15 pm »

Satfrat,

Thanks for posting the photos. Nothing like a billboard to attract potential buyers. For some reason I was only able to post a link to my gallery and not the actual pics.

Bigfish Ken,

Thanks for the bump/recommendation.

I agree that this pre performs well beyond its price point. It served me well for over 3 years. I'm not selling it because I had any issues with the sound quality but I'm getting into vinyl and needed a phono pre and more connection options so I decided to go for an all-in-one unit.

-Roy

Plink · « **Reply #12 on:** 13 Mar 2009, 01:30 am »

Yep, clearly an amazing deal for $475. Octals are great tubes and 12SN7s/12SX7s are cheaper but just as good.

rajacat · « **Reply #13 on:** 13 Mar 2009, 08:44 pm »

rajacat · « **Reply #14 on:** 14 Mar 2009, 04:55 pm »

Weekend bump

rajacat · « **Reply #15 on:** 15 Mar 2009, 07:02 pm »

Big Red Machine · « **Reply #16 on:** 15 Mar 2009, 07:47 pm »

What is the "center" level and output for?

Do you switch on the fly between tubes?

How long is the umbilical?

rajacat · « **Reply #17 on:** 15 Mar 2009, 08:29 pm »

Hi,

Here's a quote from the users' manual.

" The signal input/output jacks are located on the rear panel of the preamp chassis. RCA jacks are provided for two stereo line inputs and outputs for left, right and center. The subwoofer output is connected to the center channel."

The front panel controls of the preamp comprise separate level controls for the stereo (L and R), the center channel and the source input selection.

" The heater voltage sWitch on the rear panel permits use of 6SN7GT tubes in the left and right stereo positions only. The center channel tube must remain a 12SN7GT"

I haven't changed tubes on the fly. I don't see a reason to do it.
Of course it's important not to change tube types without adjusting the heater switch.

The umbilical is 36"

-Roy

fredgarvin · « **Reply #18 on:** 15 Mar 2009, 09:14 pm »

PM to you...

rajacat · « **Reply #19 on:** 16 Mar 2009, 05:00 pm »

Last chance! Tomorrow this sweet pre will go to Audiogon.