Hi-Fi?

[jckid649]

Can anyone here point me to some good materials on building quality hi-fi stereo equipment? Particularly I want to build a stand alone unit that contains a tube pre-amp, turntable, and quality vintage speakers.

I would really like to have some good information on the various types of pre-amps and what options are out there, what sounds best, and on the various vintage speakers and what has the best sonic qualities.

My wife and I were talking about how her old grandmothers stereo had such rich and deep quality to the sound and how nothing produced today comes anywhere close to this.

[xtian]

My wife and I were talking about how her old grandmothers stereo had such rich and deep quality to the sound and how nothing produced today comes anywhere close to this.

Install a low-pass filter and cut the 10k+ highs out. It will sound like your old console. Joking, but serious. I have a 1962 Packard Bell Space Age Stereo console. Sounds great with jazz and classical vinyl. But sucks at playing any modern tunes.

[jckid649]

Yeah but I want to build something that replicates the good stuff from the golden age of stereos from the late 50's through mid 60's. Nothing sounds like that anymore.

[galtjunk]

Look at diyaudio.com
There are schematics available for all kinds of amps and preamps.
I built a pair of single ended triode amps based on a design from decware.com. It is about 2 watts per channel and cost around $250 to build. It sounds really good but it requires the use of really efficient speakers.
I am currently looking at building a pair of mono blocks using KT88's at about 6 to 10 watts per channel.

There is a guy out there selling kits for a 125 watt PP amp that uses 4 kt120's per channel. It costs about $900 per channel plus tubes

Beware! You are about to enter a world where people will spend $400 for a power cord or $300 per foot for speaker cable.

Check ebay for old H.H. Scott equipment.

Good luck.

[Cliff Schecht]

Check out my buddy Pete's website: www.pmillett.com

Lots of cool projects there and also hundreds of tube books (at www.tubebooks.org specifically).

Like others said, hifi can quickly become a money pit. Especially with tube audio, the caps and tubes alone are very $$$ if you go with common types. I like using el-cheapo odd-ball tubes that you can (mostly) get for cheap on eBay and the like. I'm all about saving money when it comes to my tube projects, it's a very expensive hobby..

On another note (not to hijack this thread), Pete and I discussed a BF 100W Twin build using two 3E29's in the output stage. I've got the tubes and sockets to do it, I've just been pretty tied up this year (that KT-120 build sat on my bench for months ). He even gave me some nice iron to build that amp, I just haven't had the time yet! Plus I have no real use for a 100W Twin..

[Aurora]

DIYAudio is a very good site, with tons of info, - but it is also a site filled to the brim of controversy around resistors, capacitors, cables...... anything that sounds familiar?

There is plenty of info around the net, but the real classic amps often have componets that are hard or impossible to find, - like McIntosh transformers.

My best bet, if you are not looking for Ultra-Fi, is to base something on the old Dynacos, -PAT-3 pre and perhaps ST70 or 2x MkIII power amps.
There are plenty of parts and circuit boards on the market.... even full kits.
Just my 2c.......

[Colossal]

DIYAudio is a very good site, with tons of info, - but it is also a site filled to the brim of controversy around resistors, capacitors, cables...... anything that sounds familiar?

Haha, for sure! If you thought the pitched battles and partisan verbal warfare over which resistors and caps sound good in guitar amps, spend a few hours on a Hi-Fi site! Great information though.

[Aurora]

Caps and resistors are just peanut discussions......
Cables, though, - loudspeaker cables particularly......
Oh, my.... no wonder there's still wars in the real world

[rp]

Particularly I want to build a stand alone unit that contains a tube pre-amp, turntable, and quality vintage speakers

No no no on the TT. They got away with consoles way back then with rumble filters, extensive tone controls, cartridges with knitting-like needles at 5grms and high mass arms (When you wore out your Chubby Checker 45 you went to Woolworths and got an other) and turntables and arms with bearings already so rumbly that sitting in a console mattered little. Your TT should be on a wall stand unless you have very solid or stone floors. Really, do not mount the TT with the rest of the equipment. Cartridges can also pick up hum.

That old rich sound is a combo of marketing, old ears tuned to classical music, plenty of 2nd order harmonics, inability to reproduce highs, fortuitous colorations, and undamped resonant old wood work. Living with it today would drive you nuts, and there is a sweet spot btwn old an modern. Don't mistake modern mass market low-mid market Asian junk for old industrial products like 50s Marantz, Fisher, Scott, Quad, Leak or even a Sears console. In 1958 a stereo system was a big investment, 2 years on the installment plan. You should compare it to boutique audio today (and good boutique audio at that.)

The hifi info on the net is infinite. I, myself am partial to the British flat-earth school (look up Naim and Linn) while ss it is much closer to the sound aesthetics of '50-60s tube audio - truth to music, tone, and pace, rather than to hifi dazzle and 3D effects.

Pick up an old basic Sondek or newer Rega TT used and a high output moving coil like a Denon 110/160. My fave cheap cart is the AT95, emphasizes scratches but it's limitations / distortions actually add old school grunt and richness. For the rest maybe build a Mullard 5-20 or the like, pre's with phono stages get more difficult, you might be better off just buying a phonstage and simply putting a passive pot on the amp. IMO the Brits owned valve audio in the PP acoustic suspension era - 50s-60s. The US you must go a little further back with horns and triodes. Research that too, you haven't lived till you heard a totally rebuilt big horn triode sytem - dynamics like nothing else, something that rarely exists in modern audio. That might be a fun way to go, look up Lowther.

BTW you'll find building true vintage amp & pre clones, with tube rectifiers and low filtering, while nice and full and rich to be slow and soft and, and while very musical also low res. Musicality is a drug but so is resolution. There are modern styles to copy that have tight, fast(er) bass and good resolution while remaining musical. You can find schematics for amps like CJ MV-45s out there. Use Hexfreds is you go ss, otherwise if you simply clone a vintage amp/pre schematic don't sub fancy caps and resistors - you will mess up the voicing and you will hate the results.

As for speakers DIY is hard and will require total dedication / learning plus a wood shop. Nothing made today sound like what you like about old school. Hunt down on audiogon / ebay some still good 80s, BBC voiced speakers like Rogers (avoid titanium tweeters models) or Spendor. You can find 20 year old examples in fine shape for around $300.

Have fun, as others said watch your wallet!

[Colossal]

Great, great summary RP. Thanks for the information. I want to build a nice tube stereo some time myself. I've got some great old glass I've been collecting and saving for such a venture.

[jjman]

I recently build my 1st audio amp after surfing diyaudio for a few years. It's a stereo power amp with one 12a(x/t)7 driving a UL SE 6v6 per channel. Already have plenty of those tubes laying around from you-know-what amps. I kept it as basic as possible. Output trannies are very expensive for SE hifi.

It's a different world over there. Cathode/coupling capacitors are evil, PS filtering is colossal, the inductance of resistors is a focal point, and transistors on cathodes and/or plates are prevalent. Be prepared to unlearn much of what is good for guitar amps.

You mention a tube preamp but what is the plan for the power amp?

[rp]

Output trannies are very expensive for SE hifi. You mention a tube preamp but what is the plan for the power amp?

I read a review of OTs on the web somewhere, little SE ones but for hifi, and the standard edcors came in 2nd after some fancier stuff, the universal hammond was worse and as a bottom benchmark the triode champ OT was rejected totally. So maybe edcor will get you 80% of the way there. Now if the OP's goal is a a real old school amp, with the inherent limited bandwidth and colorations, an Edcor might just get him 97% of the way there. And, you know a Dynaco ST70 circuit with a modest $350 of Triode iron will envelope you like your grandma's old couch. Not for nothing they still resell well in any condition and people are still selling clone kits after 60 years.

[rp]

It's a different world over there. Cathode/coupling capacitors are evil, PS filtering is colossal, the inductance of resistors is a focal point, and transistors on cathodes and/or plates are prevalent. Be prepared to unlearn much of what is good for guitar amps.

Pre rock guitar amps were designed to be as linear as their cost/market allowed so if your goal is a nice vintage hifi amp clone, and amps from the 50s are nothing to sneeze at, you are pretty much just building a guitar amp that you're not supposed to ever crank. Hifi had some fancier stuff going on but nothing extreme like today, except some very alchemical ot's - Mac, Quad, Marantz.

There are also some modern views that any silicon is detrimental and they'll use tube rectifiers and zero regulation. I worked for a Shindo dealer for a while so I had the very rare experience to try much of the very apex of old school / modern and it's very very very good. I was very skeptical at first too - thought his whole thing was a high priced tag gimmick for boys with toys investment bankers, but it's not. It's amazing how far you can take strict 1950s technology, or 1930s for that matter. How shindo got dead black silence out NOS parts was just unreal! The real limitation of the valve era was the source equipment (bad tt bearings - no one till Linn in the 70s really succeeded at taking the TT too the nth degree) and the speaker materials (for acoustic suspension anyway).

I really want to build the original 6J5 Williamson, bet it sounds nice if your expectations are right. Most guys on the hifi forums are all living in 2012 and building for 2020, a worthy endeavor that too.

hahah looks like we are now a hifi forum. Tom please put a stop to it!

[Phil_S]

I'm not a hi-fi guy, but listen to music and I'm willing to put in my 2 cents, right or wrong. Here are a few thoughts:

1-No one needs more than about 20-30W for (average size) living room use. OK, you want to power a second pair of speakers in another room, consider 40-50W just because you can. The point is, EL84's or 6V6's will do the job nicely. If you live in a castle or a mansion, then the comment doesn't apply -- you have the money to spend on the best there is to offer.

2-Hi-Fi means uncolored sound. There are lots of decent circuits out there. Pick one and build it. Go for something neutral. Watch what you do in the way of hi/lo filters and tone stacks.

3-Put your money into the output transformer and speakers.

4-Lots of "taste tests" have been done, tube to sand in this area. People like sand. People like tubes. Too many choices, most are good.

5-Much of the hi-fi discussion is about stuff most people can't actually hear. The average adult, 30 or over, has high end hearing loss. IMO, you can't compensate for that.

Before building anything, I think you will get the most bang for the buck with a new pair of high quality speakers!

[Aurora]

Sorry guys, but some of this is just plain wrong....

Although building an old-style console does require quite a fair bit of woodworking, it is techically speaking a virtual no-brainer to achieve a good result without too much money and without any esotetic parts. This is the very reason for me recommending the Dynaco ST-70, as the power amp. The St-70 is the original source of teh A-470 output transfomer, so much recommended here for the TW Rocket. The ST-70 is fairly popular in the HiFI crowd as an entry level into tube HiFi. Paired with a reasonably good preamp, like the PAS-3x, or another no-frills tune pre, and then with a reasonably good loudspeaker design, of which the internet is crammed, will make an oustanding console, and soundwise very much better than most of the classic consoles, I do agree, however, that integrating a TT into the design may not be the best of ideas, but it can surely be done.
If the OP is still interested, I'll be happy to contribute a few ideas, but the response may not be immediate... I do have a few other things to attend to

EDIT: I agree, - very much of the High End HiFi talk is just plain old BS