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Decware Handwired Amps

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Have any of you guys listened to any of the 2 or 6 watt Decware Tube Amps thru CWs or Forte's?

Was wondering if there is any punch at all from the 2 watts.

Thanks,

John

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Although I haven't heard the Decware amps, they do enjoy a good reputation. As far as power goes, it all depends on how loudly you listen, the size of your room, listening position relative to the speakers, the presence or absence of sound absorbing materials, and so on. CWs can produce an amazing sound pressure level on even a quarter watt. Some recent near-field experiments with them have proven that point. More information about your room and listening habits would be useful in giving advice.

Maynard

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I've used the forte II / Decware combo. Good points from Maynard, it's highly room dependent. 2 watts won't crack the plaster but it will hit hard within it's means. You'll get the best results by taking your room's acoustics and speaker placement into account so that bass is as good as possible to start with. This is compounded by the amp's high output impedance and resulting response aberrations.

In my experience, it's the woofs where these high output impedance amps will have the most issues. Specifically, the woofer output is slightly reduced compared to the mids and highs (which both measure flat and sound fabulous with Decware), with peaky response down low. How this works out in your room is the big question.

With the Decware's reduced bass response through the fortes, corner placement is pretty much a necessity just to get back up to 'flat' (have to put that in quotes because all room's modal response is a mess...by flat I just mean a reasonably even octave to octave balance). Corner placement brings up the lower octaves, but will also raise the peaks. If those peaks and your room's modes coincide, it's boomin' and ugly; if not, it may sound pretty good, particularly if you have some bass traps in the room.

This is one of the few cases where fool's bi-amping can pay dividends. Not only is the woof's response altered due to the source impedance thing, the Decware amps do have audible power supply hum (only really audible within a couple feet from the speakers, but it's there). Both issues are sidestepped by passive bi-amping. I run both ways, mood dependent, using a modest ss amp for the woofs.

In my small-ish 13x18x8 room, I have my fortes oriented on the short wall, deep in the corners, cross-fired/heavy toe in, and raised up about 10" off the floor. Raising them up is another variable to manipulate in the room/bass battle, and as a bonus gets the mids up to ear level for better imaging. They measure reasonably flat, dig deep, hit hard, and, surprisingly enough, the bass is more on the "dry" side than the boomin' side, in spite of their corner placement. With the Decware amps, this arrangement works very, very well. Anything up to 95db at the listening position is within striking distance of the amps capabilities. The imaging is ridiculous, beaucoup source ambience and very little local room sound.

Hope this helps. You could probably scale up everything I've relayed to apply to Cornwalls paired with Decware.

Edited by Ski Bum

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thanks for the input. bottom line is, I have a pair of forte ones. I have spoken with Steve, and he told me that any placement within

even a few feet of your back/side walls will really degrade the soundstage. now, my room is average width, but about 30 feet long. it's a den and my Dad and I used to be able to, by angling the den, create an official 33 foot air rifle/ pistol "range" :wink: . Also, the ceiling is rather low so I am not sure if that is good or bad. I guess talking the 2 watter, it would be good, but I can not get out of my head how emphatic he was that the speakers NEED to be out and away from walls to make you imagine a real stage, with proper left/right, as well as depth, and instrument placement imagery to be ideal.

I assume I would put some slight camber {Caster?} or toe in as well but just mildly so, to help improve the imagery of the soundstage. Ie., speakers pointed IN, but by no means AT your ears. And yes, raising them, IMHO, would be immensely helpful for instrument placement...

Does any of this sound correct, or more like the ramblings of a mad man. Quite mad, actually.~ Utilizing British Accent. :D

BTW, what is the 1 watt@ 1 meter {or whatever the official measuring unit is} of the Forte Ones? I vaguely recall 98db? Sound right?

Thanks!

John

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I don't agree with what Steve told you about the soundstage degradation if the speakers are within a few feet of the back and side walls. It's still possible to attain a very realistic stage without pulling the speakers out/into the room; but, that will largely depend on where you sit in relation to the speakers. And, of course, that will also determine how much power you need. For example, if the speakers are placed six feet apart and your listening spot is six feet away (typical near-field equilateral triangle arrangement), the acoustic contribution of the room, even at moderately loud levels at the listening spot, will be greatly minimized. On the other hand, if you listen from 20 feet away, the power requirements will greatly increase as will the room effects. So, much is going to depend on your preferred way of listening. The toe-in of the speakers will have an effect on the soundstage and the correct amount has to be determined by experimentation. Doesn't Steve still offer some kind of money-back warranty? If so, it pays to order the amp and draw your own conclusions.

Maynard

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Your fortes are ~95db/w.

Steve is incorrect. I've tried my fortes in such a free standing situation, and the results are anemic bass and very strident mids and highs. It's ugly, and I would advise strongly against it. I'm just trying to provide some unvarnished advice here. I wish I still had all the measurements I took when kludging my own system into shape, but what I said previously is fairly representative of reality. The woofs will play 2-3 db lower than the mids and tweets. You remove boundary reinforcement and tonal/freq balance goes out of whack.

He's also incorrect in terms of imaging/sounstage; your fortes don't splash the walls with mid and high frequencies, so you can place them close to walls (keeping toe-in appropriate to manage this as well) without much compromise. In my situation, the depth of field of the sound stage is so convincing it almost causes vertigo. Fun stuff. And as I mentioned, the soundstage is dictated primarily by the source cues, not my room. If the recording is from a medium venue and captures the ambient and spatial cues, that's what it sounds like in playback, not like a small room at all. The image is huge, side to side, low to high, front to back, with good localization and realistic scale.

There is a highly educational thread buried here about corner horn imaging FAQ's that any Heritage or extended Heritage owner should take note of. Great thread full of useful tips.

Honestly, Decware's little amps are great if you have a small room, and worth a little hassle to optimize your room and system around, but your room is far too large for 2 watts. Maybe you could go for a pair of his $12K monoblocks. :o

Edited by Ski Bum

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Thanks guys! Maynard, what type of tube amp are you using? I assume you built it, so can you fill in wattage, tube types etc.

At what distance are you listening? The 6 feet you mentioned, my GUESS is that it's a bit more than that, but please, fill me in.

Ski Bum, THANK YOU for the link. I have been not using my audio equipment for the last number of years, as I got into other

hobbies, that take up immense time. If either of you guys have a link, or ebook explaining todays latest TWO CHANNEL Hi-Fi

options, that would be greatly appreciated, too.

I know just enough to be dangerous... SACD, DVDAUDIO, BLURAYCD AUDIO, FLAC, Kilobytes/ Second, "Record" Re-emergence.

DACs, Headphone amps w/ Built in DACs, HiFi Mans expensive "I-Pod/" MP3 Players..... basically, I need a Letterman Top Ten list

that separates out the Marketing B.S. from products that actually produce a 10 fold better listening experience than putting a Sansa

MP3 player into a Bose Bluetooth Soundwave thingy.

I am actually amazed at how little I know. For a glimpse into my other; all time consuming hobby, check out my post on the "Best three cars" thread.

I wrote it, under the influence of Norco, prescribed because I spent 6 hours in a hospital ER, as I could not raise my left arm above mid-thigh level, and I figured I had had a stroke/ heart attack. So, me being me, I rush to the Hospital TWO WEEKS after the first symptoms, to be told I have a

torn Rotator Cuff. See, I am starting to ramble again. Anyway, I delayed seeing a dr. TWO WEEKS, but when I dropped my Nakamichi, Late 1980s " vintage" Receiver because I suddenly lost all control over my left arm, I decided, "Screw with me, Aight. Screw with my Audio Equipment, no matter HOW

outdated it may be, I'm in the E.R. 10 mins. later"!

Also, while writing this, I figured out just how to save $20,000 in mono-blocks! Move my Audio Equipment into an empty bedroom that already has a "Vintage", ie. Old as Hell itself, 35 inch TV that weighs at least 140 very front heavy pounds! :lol:

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John, that's quite a story you presented about your torn rotator cuff and dropped receiver!!! Isn't is amazing how we prioritize things? Yes, all the amps that I use are my own designs. Currently, I'm running only low power SEPs and SETs with power output ranging from around 1/3 to 3 wpc. By popular demand I've been concentrating on the low power stuff exclusively as most of the audiophiles I know have the proverbial "champagne taste on a beer budget" and don't want to spend more than $250-300 on an amp. My listening is exclusively near-field at this point using the 6 foot equilateral triangle arrangement mentioned. Sound pressure levels of 80+ db are too loud for me, so power is of no concern at all- most of my listening doesn't require more than 1/10 wpc. The RF-15s that I use are rear ported, and have a fairly high crossover frequency between the woofers and tweeter, so I need to keep them out from the back wall by around 24" to create the low freq. and midrange response that I like (with your CWs that is not necessary- they can stay against the back wall if you desire and the imaging and sound stage will be excellent). If you have some experience in building tube type electronics, and working with potentially lethal voltages safely, I can give you schematics for virtually anything you want to build. Drop me a PM any time. Btw, where are you located? I'm in NJ which doesn't seem to be a hot spot of forum members! So, hope that helps a bit. Gotta run!

Maynard

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Thanks Maynard! I am in Glen Ellyn Illinois, 25 miles as the crow flies from the Sears Tower. OK, to be

PC, it is now called the Willis Tower. I heard they changed the name it tribute to Gary Coleman, after he

passed a few years ago.{ Poor attempt at humor } :(

I wonder what you would charge for building an amp based on this tube: A Russian GS-35...

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The GS-35 is a popular tube for RF applications. In fact, some hams have constructed linear amps around them with good results. I've tackled some crazy audio amp projects over the years, but trying something around one of the "monster" transmitting triodes isn't among them. I can't imagine what it would cost to have the required custom output transformer made. The weight of it alone would make me run!!!

Maynard

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Hi John ,you are welcome to try my EL-84 tube amp Decware any time to see if it will work for you. I'm in Shorewood 60404

post-22043-0-07020000-1387252432_thumb.j

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That's a generous offer, furface, very cool. I see that you have the alternate "EX" output trannys intended for higher impedance speakers, which has implications when paired with the OP's fortes. If the OP takes up this offer he should realize that going in, and to not judge the flea power approach or Decware in particular based solely a less than ideal pairing. (It may sound better than this post suggests, I just don't know, but I do know that it will have an effect.)

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FurFace, That IS an amazing offer, however If possible, I would prefer to listen to the Dacware Amp at YOUR HOUSE. I find that borrowing things

is not a good thing for me to be allowed to do{per Da Wife}. I'm kinda like Cosmo Kramer when it comes to borrowing. The item, really doesn't matter if it is a cooking spatula or Puffy Shirt, usually is worse for wear upon return. ~Sienfeld, again.

Shorewood is not too far from me, so maybe we could set up a time, after this left hand can be raised enough to use the blinkers in the Mazda3, as opposed to threading my right hand thru the steering wheel, to indicate a change of lanes! Granted, driving has been more "interesting" lately, but probably not in a good way.

And finally my new friend Maynard. My gs35 tube, initially built for HF communication in Russian tanks, works well in my Ham Radio Amp. And as my

mentor, who built the amp from scratch told me, "There is a good chance even YOU can not break this amp". Well, that remains to be seen.

However, speaking of power transformers, it is not at all heavy... compared to the transformer we used to drive my Eimac 1500a Tube. THAT thing

needed a variac to back the voltage DOWN to 6000 volts, in order to not melt antenna wire. O.K., since I was the guy who had to carry the 8000 volt

transformer back and forth to the truck on several occasions, I do believe you guys helped me figure out how I tore my rotator cuff!

Maynard, can you do a quick calculation as to the weight {in pounds please ;)} that a transformer capable of 8000 volts on a 240 line would weigh?

We may have found the answer to the source of my injury!! Also, while being nice, big tubes, the THD is probably a tad above what Steves amps run... IMHO. Thanks Again, John

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John I'm sure we can work something out for you to hair the Decware. It would be nice for you to hair it with your set up to answer your own question about what 2-3 watts can do with the speakers you have and your room. I get to hair what 2A3 amps can do with K horns at my friends man cave and i will say there is some punch with 2 watts or so.

  • Like 1

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John, you remind me of a local ham I knew who ran 5-7 kw output on 80 CW!!! I don't remember which tubes he was using but, when transmitting, the lights of his neighbors' houses (as well as his own) dimmed slightly. I can still see the gorgeous glow of the banks of mercury vapor rectifiers which he used in the p/s. The good old days!!! As far as an 8 kv xfmr goes, much depends on how much current you need/want to draw. If it is no more than 100 ma or so, you could play with a neon sign xfmr. Your request also minds me of a huge Tesla coil my EE room mate and I built when we were doing our optical grad work. The secondary was 6 feet tall and we could easily draw an arc of a few feet. We once connected it to the door knob of our room when a friend was on his way over. He never spoke to us again!!! In any event, if you need an xfmr which is more substantial, contact Magna-Power Electronics. They can design and build anything you want:

http://www.magna-power.com/

Enjoy!

Maynard

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A1UC.... I was never interested in art of any sort, but... I may be caving... Beautiful Amp!

Not mine but I look at it everyday :)

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:)

Edited by A1UC

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Thanks for the info guys! Here is my update. That damn heavy-As* Transformer did NOT cause a rotator cuff injury!

I had an MRI done Monday night, turns out I have arthritis! I guess time waits for no one, and it ain't waiting for me...:-(

Fur Face, I think I would be thrilled to take you up on your offer. Three things have to happen first. Enough strength to carry the fortes from the den to my spare bedroom, no -7 degree friggin temps, and a time when the wife is lunching with her mother so I can run down and grab it and be home before she notices I was gone. ;-)

So, thanks again for the offer and all the valuable info you guys have provided!

I hate to ask this for fear of being booted off the forum, but... Is it remotely possible that my quad core AMD, HP pavilion desktop with bluray, SACD, DVD audio playback, run into a decent DAC be useful as a source for my music? Or is everyone spitting their beer on their keyboards laughing right now?

John

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