What Octal tubed preamp do you like?

nodiak · « **on:** 4 Apr 2006, 09:49 pm »

I am actively seeking to buy an octal based preamp. Currnetly looking at Mapletree 4A SE (has phono) and Space Lab Tech QA-112 (no phono).
Anyone with experience of one or both? Or other in similar price range ($800) or less.
I am close to ordering time.
Thanks, Don

roymail · « **Reply #1 on:** 4 Apr 2006, 11:31 pm »

Maple Tree gets high marks from dmason. Highly recommended by many others. I'd love to have one.

Roy

TomekZ · « **Reply #2 on:** 5 Apr 2006, 12:53 am »

Really like my Mapletree 4A. Likes tube rolling. 12sx7 or nice 6sn7 for the line section. This preamp vs. passive with gainclones and t-amps gives warmth and roundness to the midrange and softens the treble (filters out digital nasties) and does not add anything to bass impact (as I've heard about the 6sn7 family of tubes in general). A very coherent sound, esp. good with single driver full range speakers.

acresm22 · « **Reply #3 on:** 5 Apr 2006, 12:56 am »

Don,

I have a Mapletree Line2A SE (custom built with a third channel...so technically a Line 3A) that I'd sell you. PM sent.

D.

JoshK · « **Reply #4 on:** 5 Apr 2006, 03:30 am »

I owned a Maple Tree Line something and thought it was a gem, 'specially for the money. It replaced a $3000 Cary SLP2002 and I didn't feel like I missed anything (except the remote and headphone amp).

But, what is so special about Octals? I see a lot of audiophiles going on and on about them. Why?

nodiak · « **Reply #5 on:** 5 Apr 2006, 05:49 am »

TomekZ, of the Mapletree's I am especially interested in the 4A SE because of the phono. Do you use the phono enough to give an opinion of it? Have you compared the 4A to other small tube preamps (like 6922, 12au7,etc.)? i wouldn'twant it toooo warm or round.
Josh, do you remember yours to have "big air" or "big tone" or "great depth" ? These are a few things I've heard they do.
My biggest concern with octals is whether they maintain a "liveliness" to the system. Probably tube dependent, if so what tubes?
Don

Parnelli777 · « **Reply #6 on:** 6 Apr 2006, 12:51 am »

The Wright WLA12A is a <really> nice little unit. I love mine :^) Less than $900. This fellow George Wright has been doing this stuff for a long time, and he knows his, uhh, stuff- especially those little thermionic devices.

http://www.wright-sound.com/scripts/prodView.asp?idproduct=10

Brad · « **Reply #7 on:** 6 Apr 2006, 02:43 pm »

slightly off topic, but I saw this blurb on the Wright Sound web site - very interesting: EL84-based integrated amp.

New Products: We have two new products we are in the process of devolping for our customers. First is a special low hum and noise Mono Block amplifier, the Mono 7 horn power amplifier. With seven watts of 300B SET amplification this amplifier fills a void for those who love the sound of the 3.5 Mono but need more power. The second product is our first integrated stereo product the WIA1515, a 15 watt EL84 push pull line, power and headphone amplifier, so called an all in one amplifier. Offering for the first time, those who want the clean detailed sound of Wright Sound, to own have a smalled compact product for the office, den, apartment or even the main listening room. Many features like front input jack for MP3 / Ipod protable devices, four rear inputs, two with 3.5 stereo jacks for sound card interconnects, speaker off- on switch for private headphone listening as well as having friends enjoying your favorite music.

chadh · « **Reply #8 on:** 6 Apr 2006, 03:21 pm »

Well, I have no experience here, but I've been lusting after the Space Tech Labs QA112 for months now. Finances don't allow me to indulge myself fully, but I have (just this morning!) ordered the QA001 (Albert's entry level pre-amp, that comes without tube rectification).

If you can wait for three to five weeks, I'll be able to tell you how it sounds.

Chad

miklorsmith · « **Reply #9 on:** 6 Apr 2006, 04:14 pm »

Quote from: JoshK

But, what is so special about Octals? I see a lot of audiophiles going on and on about them. Why?

Dmason is the pusher around here. I've had exchanges with him before about the small, 9-pins vs. octals. I had the Modwright in my system at the time which I felt was the perfect partner for my Clari-T. The good doctor felt the 9-pin tubes did not sufficiently flesh out the tonal character of instruments and that the bigger tubes added more tube bloom and tone.

His experience is much greater than mine with different tubes and I've never heard an octal preamp. The ones I've seen have a much lower signal-to-noise ratio (usually in the 80's) than the Modwright which supposedly measured over 120 db.

Now, if the Moddie had room correction built in. . .

Dmason · « **Reply #10 on:** 6 Apr 2006, 04:23 pm »

Try one with a T amp and see what I mean. Let your ears decide. Screw numbers, the best test equipment in the world is glued to both sides of your head.

I liked the sound of 6xx7 tubes enough to have one built. A tiny, single tubed summed deal. Minimalist. It completes the picture. It stays.

woodsyi · « **Reply #11 on:** 6 Apr 2006, 04:57 pm »

Quote from: miklorsmith

Dmason is the pusher around here. I've had exchanges with him before about the small, 9-pins vs. octals. I had the Modwright in my system at the time which I felt was the perfect partner for my Clari-T. The good doctor felt the 9-pin tubes did not sufficiently flesh out the tonal character of instruments and that the bigger tubes added more tube bloom and tone.
...

I really think this is an issue of equipment matching. Any lean and accurate source and/or amp/speaker combination will benefit with octal pre in general but it could also become too soft if you already have tube amp with octal drivers . I liked SWL with my system -- it added more pace and rhythm. It definitely gave a thumping bass line and played the the bass notes clearly. While it's in the shop for upgrade, I have fallen back to my old octal preamp LAD2http://www.vongaylordaudio.com/product_html/propreamplifer.htm. With a pair of NOS Red RCA 5692 driving them, vocals get that lovely bloom that I frankly have missed. It's different and you just have to listen for yourself with the type of music you like on your gear in your room . Is that enough qualifiers to cover all bases?

TomekZ · « **Reply #12 on:** 6 Apr 2006, 08:28 pm »

More about the Mapletree 4a SE preamp. Other preamps that I had around the time of finalizing to keep the Mapletree about a year and a half ago: a Audible Illusions 3 and a AVA 5. Of those, I thought the Mapletree most weighted in the lower mids and most forgiving in the extreme treble, but it was not in the least overbearing. About the phono section: I run a Linn with Rega arm and a Grado (MCZ --a few years old and then the step up from an 8Z) and also tried a Shure V15 V. Actually, I liked the Audible Illusions better for phono--more bass authority--, but not for line. Alas, like many, I do think phono superior, but I also like more the new and different music that can only be heard on CD.

ashok · « **Reply #13 on:** 7 Apr 2006, 04:35 pm »

Hi everyone,

I have been a lurker for a while now, with just a post or two. I have been following the octal preamp thread with interest.

Here is a link to something that I just ordered from Autocostruire. http://www.autocostruire.com/catalog/product_info.php?products_id=304

A 6SL7 based buffer that works on 12VDC. I am not exactly sure how it is going to work, but will find out soon enough. The heatsink in the picture is probably for the regulator that derives the heater voltage.

Ashok

Dmason · « **Reply #14 on:** 7 Apr 2006, 05:23 pm »

I think the Autocostruire idea is good. Minimal circuit, summed channels, and makes life easier to "budget" for a nice NOS 6 series tube which is what will give it its sonic signature. I recommend that with these tubes, the circuit is built around the tube. They tend not to be subtle, yet do not get in the way either, the old ones that is. Ken Rad, Sylvania, old RCA etc.

I would love to see a Red Wine Audio optimized solution using the Autocostruire circuits. They have been invented to COMPLETE the T amp sound. Proof positive the notion is "real," in my opinion. Please let us know how things work with the Italian invention.

Meantime, I heard the Mapletree Octal with a deHavilland tube pre both using NOS 6SN7 and I would prefer the deHavilland, but not at five times the $$$. It really was only subtle differences. The Mapletree tube preamp products to me seem a bullseye solution when using Gainclones and T amps. We're seeing this all the time now.

nodiak · « **Reply #15 on:** 7 Apr 2006, 08:33 pm »

Nice to read all the replies, a good conversation. And thanks for links and ideas - Mapletree, SLT, Wright Sound, deHaviland (in my dreams says Grandfather clock), and groovalizer audiophile stocking stuffer (may have to have a yard sale and get that, very cool). Open and anxious to hear any and all reports on these items.
Definitely agree with system matching , as we all must.

In that view I am solid for now with Audiosector nos dac, Sony 685 cd, Vinnies iMod, Gainclone amps. *

I will always try different speakers (diy), and for the time being will go for OB's, as have proved best to me. I have a pair of 15" Hawthorne OB designed bass drivers coming, will use from 40-300 hz depending on which widerange driver is being tried: Fostex 103a, 107e, 108ez; 8" hemptone, low end Tannoy 6.5" coax (made for ceiling mount), Hawthorne SI's, vintage Saba greencones (I think these are worn out tho), 10's from KLH model 6 (last 2 w/tweeters).

The big tube octals should carry farther with the warmth I was getting with 6922 linestage, and open things up to a big perspective that I should like (I enjoy a little "weight" to the music, I believe in gravity - as long as am on earth may as well act like it!). I'm not into sweet spot limits or ultimate analytics. But I don't want to go too far the other way. With tube rolling it appears 6xx7 and 12xx7 (thinking Mapletree) may give a range I'd like. Currently trying an upgraded MiniMax pre that is really great but stops a little short of where I think octals will go, according to your replies and others.
All up to individual senses, etc.

(And then there's "the room" - duuhdum, duuhdum,...)

Thanks, keep it coming...
Don

*Probably better cd transport later, iMod still breaking in, maybe Charlize amp when built, turns out my eyes aren't steady enough now, will get local tech's help to build. Tube amp possibly down the road from here.

GHM · « **Reply #16 on:** 7 Apr 2006, 10:07 pm »

What ever you decide make sure the input impedance of the tubed preamp is at least 100k ohms or so. Stay away from anything lower than 50k ohms. The Audio Sector DAC really opens up on 100k or higher inputs.

The addition of the tube stage will put you smack dab where you want to be. I doubt you'll find a tube amp in the price range that matches the mix of gainclone and tube preamp..it is world class sound IMHO.

doorman · « **Reply #17 on:** 7 Apr 2006, 10:19 pm »

Don't forget the Transcendent Sound GG. It plays music, at an attractive price too! Don

melville · « **Reply #18 on:** 7 Apr 2006, 11:15 pm »

You might want to take a look at the offerings of Space-tech in Vancouver, B.C., Canada. I do not yet own, but have listened to, a few of his octal-tube-based preamps, and they are very special

Brad · « **Reply #19 on:** 8 Apr 2006, 04:31 am »

Thanks for the link to Autocostruire

Their little integrated with the tube front end combined with the digital amp is a pretty cool idea.