Decware SE84-DIY build thread.

[sebrof]

I had ordered the Decware integrated kit a day or two before GH started this thread, so of course I have been watching closely. I recently (May) bought a pair of 1965 Klipschorns and have been working with them to get them sounding good ever since. I had a couple of higher power amps and sold them, so I ordered the Decware to get me by until I found a 'real' amp for the long term.

It took me about 3 - 4 hours to build it. If you want to see pics take a look at GotHover's, his looks nicer than mine. I plan to permanently clean it up this weekend. The only issue I had with it is the speaker connections. It looks like there's only one way to install them, and when I was putting them on I thought there was no connection. Sure enough, no output after I tried to make music. I took them off and made a more direct connection and all is well.

Again, my plan was to get a low cost temporary solution so I wouldn't have to go without tunes. My KHorns and low power / Hi Eff is all new to me, so I wanted to do research before I bought an amp. I was expecting the Decware to sound good but not have enough power at 2 watts, but thought that at least I could get an idea what a SET amp sounds like. Also, if 2 watts was almost enough power, I might consider a 300b amp @ 8watts. If 2 watts was way low then I would look for more power.

After listening for a couple of hours I can say that I don't plan to look for another amp for a while. Its 2 watts is plenty: KHorns in the corners of a 13' x 12' x 9' dedicated room. I haven't measured with my db meter yet. But when I got the KHorns I invited a fellow music lover over to check them out. At that time I had a 100 watt EL34 amp. We listened to all kinds of music for about 2 hours. We pushed the speakers pretty hard as you would expect when you're showing them off and seeing what they can do. We didn't play any louder that day than this amp can go (of course the 100 watt amp could go a lot louder). That might give you an idea how much 2 watts is to a pair of KHorns.

It's not broken in yet and I haven't had a chance to do a lot of critical listening. I don't think it's fair to judge it just yet after having had it powered up for only 2 hours total, but what I hear already sounds very good. I have a pair of JJ EL84s and a JJ 6922 installed, so no exotic tubes yet.

I think the Decware is a bargain, especially if you are handy with a soldering iron. If you have La Scalas or KHorns or other Hi Efficiency Klipsch's I don't think you can go wrong with this kit. If you're thinking about experimenting with tubes or SET amps you might want to give this amp a try. Also available factory built.

[Guest David H]

That looked like something I could build and maybe someday will attempt.

Maybe if I can ever get me one of NOSValves stereo VRD tube amp then I would try one of these two tube preamp kits.

Good plan, its a great sounding preamp. VTA/ www.tubes4hifi.com also builds a newer version of this preamp with a larger power supply called the SP-8, available with or without phono stage.

[Guest David H]

After listening for a couple of hours I can say that I don't plan to look for another amp for a while. Its 2 watts is plenty:

I agree, I am pleased with the Decware. The Sonicap is a worthy upgrade.

Here is the Chassis I ordered from www.par-metal.com for $60 HxWxD 6 x 8 x 16

[Guest David H]

The transplant.

[Guest David H]

I also replaced the Volume pot with a stepped attenuator. The stepped attenuator is a 100K I ordered from ebay for $25.

The stepped attenuator operates much quieter that the original pot.

[Guest David H]

Next, I need to get the faceplate artwork done. These chassis have tons of room to work, and excellent cooling.

[jbsl]

I also replaced the Volume pot with a stepped attenuator. The stepped attenuator is a 100K I ordered from ebay for $25.

The stepped attenuator operates much quieter that the original pot.

Is this the type of attenuator that clicks when you turn it?

If yes I had it on the Ground Grid tube preamp and with La Scalas it was too much of a jump in volume. It was hard to adjust the volume to where I wanted it, too loud or to low.

[jbsl]

I see your new equipment critic has not left the room so I guess that is two paws up.

[Guest David H]

Is this the type of attenuator that clicks when you turn it?

Yes, these do click, but has 23 positions and excellent resolution. No problems with massive jumps. If you prefer a potentiometer stick with the ALPS blue, I used this in my SP-6 preamp and have had no issues.

[sebrof]

Thanks for the info.

There's definately some room for tweaking this amp: Pot, tubes, caps, case, etc. I need to let it settle in for a week or 2 first.

I also have some tweaking to do on my system: KHorn crossovers (on order from Mr. Crites), speaker wire.

As I said in my first post, Hi eff speakers and low power amps are new to me and I'm having a lot of fun playing around. I thought no way a 2 watt amp even comes close to having enough power, so I learned something there. My reference was Maggies and Logans that like a lot of power.

[Guest David H]

My reference was Maggies and Logans that like a lot of power.

I really like my Maggies, I still have my Logans in storage and my PS-Audio power house I used to drive them. I think with a few mods you are going to love your KHorns and SET.

[Guest David H]

I had Tim at High Deset Laser Graphics do the faceplates.

www.hdlasergraphics.com

Email: tim@hdlasergraphics.com

[Guest David H]

Before and after shot.

[Blvdre]

Pretty cool GH. That circuit makes for a good graphic.

[Guest David H]

Pretty cool GH. That circuit makes for a good graphic.

Thanks, I though the classic set circuit schematic added a nice touch.

[Guest David H]

After giving the twins a couple weeks of listening I decided to complare them to my Eico 81, Dared VP-20, and Dynaco ST-35, and I have to say without a doubt, The Decware is something special. I agree it not exactly apples to apples, but its what I have to compare to. The Decware Eico, and Dynaco all share the 6BQ5 tubes, and sound very similar overall, but the Decware really shines in the vocals, never overbearing, just smooth and natural.

At the begining of this thread, I posed a couple of questions.

Is 2.3 watts per channel enough?

This much power is plenty for 95% of my listening, for the other 5% I like a little more punch, and the bridged monoblocks fills that bill nicely.

At this price how much quality can I expect?

I am overall pleased with the Kit quality to price ratio, a couple of items I chose to upgrade were the coupling caps I upgraded to Sonicaps, and the volume pots I upgraded to stepped attenuators, other than that, I feel Steve Deckert did a fine job of sourcing quality parts for DIY-ers.

Will I really hear the EL-84 tube magic? The EL-84 tube is a fantastic contender for the title, I like this tube for its transparency, and clarity. I think the Decware amp brings out the best of what this tube has to offer. As for the magic, I have not yet seen any symbols floating in the air, but I can certainly hear them up there.

Is this kit easy enough for a beginner? Not to be too blunt, but this kit is unbelievably simple, anyone with soldering experinence and the desire, will have no issues with this kit.

Enjoy, Dave Harris

[Guest David H]

A few things I forgot to mention, this amplifier kit is popular among DIY-ers, and is often backordered. It is worth the wait.

Tech support:

The attached pic you will see that I changed the twisted twisted pairs of input wiring to coax, this was to solve a low level hum that increased as the volume attenuator was lowered to the minimum setting. Steve Deckert took the time on the phone to hand walk me through the solution to this problem, this kind of support is over and above my expectations, especially because I had modified this from the original design.

[sebrof]

I can't really add to what Dave said except to say that I've had a similar experience with the Decware Zkit1.

With KHorns @ 104db in a 12' x 13' x 9' room the Decware has all the power I need. I've had it on for about 30 hours, half of that time I've been listening to it. It's settled down to the point that I think I'm hearing what the amp has to offer and I'm very happy with it. I listened to Wilco, Steely Dan, Diana Krall, Dire Straits, Lucinda Williams last night and all sounded very good. I put Diana Krall in to get a baseline on female vocals, intenting to play one or two songs and ended up listening to every song on the album. I've never heard that album (All for You) sound better, not that I play it all the time. I'm listening to Mile Davis KoB right now and it sounds very good as well.

Take this for what it's worth because the KHorns are new to me and I'm not familiar with their sound. I haven't had another amp to compare with since I've had the Decware, but from memory of the 100watt EL34 amp I had when I first got the KHorns the Decware is more detailed, but perhaps a little less smooth. Better for the most part except for poor recordings.

This is my first DIY project, easy as it was in complete kit form and all laid out. Building it was fun, and even though it wasn't very challenging there was a bit of satisfaction after I finished and started playing music. All sorts of tweaking possible, which should keep me busy for a while. If you're driving efficient Klipsches and you're curious, this kit is a good way to find out if there's anything to the hype. I paid $300 + tubes + shipping totals about $350.

[Guest David H]

All sorts of tweaking possible, which should keep me busy for a while.

I am glad to hear you are enjoying the amp, when I talked to Steve at Decware he reccomended upgrading the coupling caps to VCaps, I am sure this would be a better upgrade than I did, but at $50 per cap, I decided to buy the chassis and upgraded tubes. The tube I chose were the Gold Lion EL-84, I also have a set of NOS RCA's, and am looking to get a set of Sovtec EL484M's. Johnny 5 purchased the new Mullards, and is so far not thrilled as to the performance, I think he prefers his Sovtec.

Sebrof, keep us updated on how your mods go.

[sebrof]

All sorts of tweaking possible, which should keep me busy for a while.

Sebrof, keep us updated on how your mods go.

Will do. I have the amp and speakers to play with.

I've got Bob Crites A / AA switchable crossovers coming, so that will be next for me. It will be a couple of weeks until I get them and listen to them for a while, before I do anything else to my system. I'm assuming that the very simple A network will work better for this amplifier than the more complex AA, but we'll see. That's why I ordered the switchable version.

After that, I plan to do the CCE (Christmas Comes Early) mod to the amp (talked about on the Decware site). I'll need to get the SV83 tubes in order to do that mod. Let the tubes break in and see how the SV83s compare to the EL84s, then do the CCE mod. Hey, might be Christmas before I do the CCE. But I doubt it, I've never been able to pace myself when it comes to this hobby.

After that...who knows.

Mike