tube amp questions

Do you have any information on DIY tube amps
Where can i but tubes, sockets and misc components?
I have a 4 way system DSC 280
2-2245s powered by 2 bryston 4b mono blocked 800 wats each in loaded horn crossed over at 80hz 104 db 1 watt
2-416 8bs in loaded horn cabinet 112 db @1watt 80 to 300 hz. Need tube amp - how much wattage?
2-2583 bentwood horns 300hz to 5k 122db 1 watt. Need tube amp - how much wattage is required.
2-2410 2301 lense mashers 5k to what ever they can do 109 db@ 1watt. Need tube amp - What wattage is requred.

I presently use a parasound 6 channel mp at 70 watts per channel and want to change to tubes

I prefer a dedicated amp per voice coil

pleas offer your suggestions

Well first question how loud do you like to play it? Your speakers seem to be pretty effecient and if it were me I'd probly run something like 4 watts per channel. But I don't need an earthshaking aural experience so even a pair of speakers that are semi efficent will get the job done for me. oh hell those are woofers haha you're gonna have to have a helll of a lot of power to drive those i would say keep the woofers on solidstate and get some tubes for the horns and if you like your current headroom as far as running your system i'd say at least 35 watts per channel. the most time consuming part of your setup will be the preamp, if i assume correctly that you are running 4 different inputs?? and if thats the case you'd probly be better off building several push-pull integrated monoblocks. Although once again you could probly save some money by just using tubes for the horns because you're gonna spend several hundred in transformers if you want to drive those woofers.

Sounds like an admirably ambitious project. If you want a dynamically balanced setup (and who doesn't?), compare the power ratings and max clean SPL for your components (actual data in the horns/cabs you'll use, not necessarily the book #s), and determine which one will reach either thermal or displacement limits first. That's your system limit. Then see how much power it takes for each of the other drivers to produce equivalent SPLs, and that's the minimum wattage you need to get the full potential out of each driver.

Even if you never turn things up very high, transients need the reserves to maintain low-distortion output. You've got efficient parts, but will still have to squeeze everything out of the top 3 you can, to keep up with the 2245s/800W. Flea-power won't cut it in this app. Just guessing, but I'll bet your current amp is sized pretty close to optimum.

To build amps for 6 channels that will roughly be in the 75/50/35 WPC class, I'd build 3 stereo chassis, to save room, and the extra time and $ the extra chassis' and power transformers would require if they were monos. Quad PP EL34s will get you 75/quad (like the 1569A), paired PP 6550s will do 50W/pr (ala Mac circuit), and a pair of PP EL34s (like the 1568A) or 6L6s will do 35W/pr. I can't recommend any kits, as I haven't used any (I just rebuild/reuse the old stuff). There are several sources online for tubes and parts, I've bought a bunch from Antique Electronic Supply, and well-pleased with them;

http://www.tubesandmore.com/

If you go with EL34s, check out the current-production JJ Tesla's. Sound as good as NOS and 1/20th the money. Current-production tubes may be here awhile, but designs that use tubes not made today will eventually leave you high and dry, not to mention breaking you in the process.

Tip; Current web discissions of anything tube propogate more magic BS than fact. This is a case where old library books would serve you better than the 'net.

Welcome to tubes, jbldriven. The DIY tube amp hobby is very active at the moment. One of the sites where many of the more knowledgeable people hang out is the Audio Asylum, and there are four different discussion forums there concerning tubes. You can go there and read the discussion, search the old posts, and perhaps ask a question or two.

http://www.audioasylum.com/index.html

My preference is for transformer coupled all directly heated triode single ended amps. These do the best job I've heard of preserving all the low level information that really puts you in the space with a good recording. Some guys like to use low powered (mine are 1.6 watt) DHT amps on high frequency drivers and more powerful push pull triode or pentode amps for bass. Your power requirements will depend on your speaker efficiency and desired listening level. With the sensitivity figures you mentioned for your speakers it shouldn't take too much power to make you happy, and tube amps of a given power rating usually sound more powerful than solid scrape amps of the same rating due to the more graceful clipping behavior of tube circuits.

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Originally Posted by SETriode

Well first question how loud do you like to play it? Your speakers seem to be pretty effecient and if it were me I'd probly run something like 4 watts per channel. But I don't need an earthshaking aural experience so even a pair of speakers that are semi efficent will get the job done for me. oh hell those are woofers haha you're gonna have to have a helll of a lot of power to drive those i would say keep the woofers on solidstate and get some tubes for the horns and if you like your current headroom as far as running your system i'd say at least 35 watts per channel. the most time consuming part of your setup will be the preamp, if i assume correctly that you are running 4 different inputs?? and if thats the case you'd probly be better off building several push-pull integrated monoblocks. Although once again you could probly save some money by just using tubes for the horns because you're gonna spend several hundred in transformers if you want to drive those woofers.

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Thanks for your helpful input. I definitely like head room in my amps. My room itself is 30 feet by 38 feet with a cathedral ceiling 13 feet

Thanks for all your responses. Will continue to pursue the amps. Probably 70/50/35 watts for starter and preamp later

You might consider Solid state amplifiers for the LF/MB. There are some great sounding SS amps to be had. Threshhold STASIS amps. And if you ever get the chance to audition the 80's vintage Yamaha M series, they are very nice sounding too. I'd stick with the following models M70/80/85 and MX800/1000(u). I use these amps in the LF section of my triamped rig and love them. As for tube amps, look at some VTL/Manley. The ST80/85. I also have a friend that uses Conrad Johnson, he's very pleased with his CJ. Tubes and JBL/Altec compression drivers, a match made in heaven! You are in for a real sonic treat!

If you enjoy playing with the amps themselves I'd suggest Dynaco. A pair of MK III mono-blocks can be had for $500 - $600. You can enjoy them as is, or have fun modifying them. What's fantastic about these amps is the amount of aftermarket upgrades that are available. They can be made pretty, and they can be made to sound as good as any tube amp available. They are an excellent choice for the DIY hobbyist. The ST-70 is probably the most popular/common model Dynaco made and they are less expensive than a pair of MK III's.

At a minimum you should have SS rectification. I don't feel "sag" adds to the music! It wasn't recorded that way.

I have highly modified MK III's (modified to the point they're no longer Dynaco amps) for the mids (L100) and a pair of SS amps for the highs and lows. This makes for a mind numbing experience! I use a SS preamp as I don't feel the tube preamp adds anything positive to the mix.