Eico HF-81 Unbuilt kit on eBay

[NOSValves]

jazman,

My father and 90% of the Ham radio world would argue with you about EICO's reputation on test equipment I believe the word my father with 50 years of Ham radio repair and rebuild expereince was "Its cheap junk" . Chris who is a well known Tube Tester rebuild guy that lives not far from me say's basically the same thing. Even mobile doesn't care for there tube testers if I remember right. They even stoop to the level as to twist the meaning of Mutual conductance on there tube testers !!!

EICO was always on the bottom of the Electronic food chain so to speak. This still doen't mean that the HF-81 isn't all that the few people here and other places say it is. But if that is indeed true it was nothing more than a fluke in EICO's normal business pratices. They copied the willianson design and maybe got lucky. I would bet every Scott I own that they didn't go one Ioda out of there way to assure top quality sound.

Craig

[jazman]

Craig,

So, still you would rather consider yourself "right " with your supposition than actually pursue a more real answer. It figures. I give up.

Klipsch out.

[Clipped and Shorn]

kh and others,

I really have no disagreements or arguments with anyone here in this thread. I have only been making overview generalizations and observations about what is going on. I have been neutral and speaking positively about all sides of all issues. There should be no reason for thinking anything else.

kh, you are not reading what I am saying. You are taking a strange defensive position when there is no need to. Nowhere did I say listening to audio is like astrology. What I said is that humans these days gravitate to both science and mysticism (or maybe a better term is the intuitive arts).

I live in a generalist world and my statements have to do with that. You live mostly in the audio world, it would seem, so you think everything I am saying pertains directly to that, but it does not. Please try to take a wider view, and please, man, do not think that I am challenging you in particular here or that I am even addressing you in my generalizations. I really do not understand where that is coming from. I am trying to remain on a truth path, so your comments of a possible insulting nature are out of line and could frankly make you look small to me.

It is certainly possible for a person to be logical and clear thinking generally, without having the unique credentials of having heard every amp under the sun. That is great that you have that experience, and we all appreciate your knowledge and can use it when you share it. Doesn't mean that if someone does not have that same audiophile experience that they do not know how to think or cannot grasp the scientific or engineering process, or do not have discerning ears. If you thought that, and I don't really think for a minute you really would, it would tend to suggest an embarrassing elitist snutty hi-fi store snob. Never really liked those types at all. Phonies in my book.

Like they accuse you of not having discerning ears so you will ultimately spend more money in the store.

{Incidentally, I have a degree in Physics from Cal Berkeley, so I am not unfamiliar with science.}

I also spent many years studying mysticism as well as art. I think I know something about the differences and interconnections between all of them.

I am a generalist, maybe you are more of a specialist. Cool, both are good.

What seems to be going on is what is called projection. There is no need for defensiveness guys, no need to project imaginary things I have not actually said onto my words, I have been taking the overview position. This defensiveness and projection is interesting and makes me wonder. It's almost as if the HF-81 is a religion? LOL. {incidentally I am not someone's disciple, maybe you see things that way, maybe you see the various HF-81 owners here as your disciples, but I have friends, all of whom are individuals I can learn from} . Damn, maybe it is a religion! LOL.

All I can assume is that my words are being misunderstood and assumptions are being made that are not justified by what I am actually saying. Can't we just get along.

BTW, I love my own Eico HF-35 monoblocks on my Cornwalls and will be using the same monoblocks for my upcoming tri-amped Altec system. I also have a pair of Eico HF-22 monoblocks that I am also going to be upgrading and experimenting with and other vintage iron as well. They have the same great output transformers! So you see I have plenty of that great Eico iron in my house as well. When my whole system is up and running I will give you all the run down about what it is and how I like it. As most things worth having, it is worth waiting for and I am very paitient with the learning curve. I am building my system one step at a time as I make discoveries about what vintgage gear works for me and my own ears. It is my own deductive process and I hope to end up with a unique system that is really suitable to me. It will be different.

-C&S

------------------

Cornwalls

currently upgrading

to all tube components

This message has been edited by Clipped and Shorn on 09-01-2002 at 03:31 AM

[NOSValves]

Jazzman,

When have I ever stated that the HF-81 couldn't sound good ?? I myself find it hard to believe but not impossible. Someone trying to paint a picture that EICO was known for there top quality products at rock bottom prices or that they had some deap secret about what made test eqiupment great or amps or whatever is just plain wrong I'm sorry. EICO was one of the lowest priced offerings in every field they serviced it was there business model nothing more nothing less.

Craig

This message has been edited by NOS440 on 08-31-2002 at 10:35 PM

[mike stehr]

I took two Eico HF-12's, the mono integrated version of the HF-81 and ditched all the pots, and selector, with the only input being the tape input or output, what ever the hell it is.

(A HF-14 on a HF-12 chassis.)

Sprague power supply cap, carbon film resistors(free),a sprague cap for the switch, and old NOS Cornell dublier oil caps for coupling, silver micas, blah, blah...

(No more dried up 40 year old parts, except the multisectional's, and one leaks, beat!)

They sound rather good, but I am new, and my opinion does not hold much validity.

Sometimes they sound rather bad, depends on the source.

They work, and a work still in progress.

But most posters here would probably listen to my gear, and run out of the place with jarred fillings, bleeding ears, severe migrain, and blowing chunks!

It's fun.

Boy! The Phsyco for Eico thread, sheesh!

See, what you do, is win the bid on this half-built kit for some outrageous price like a $1000 bucks and then toss all the 40 year old parts, and the replace them with the boutique parts like Jensen silver PIO caps, and Audio note Tantalums, Riken, Caddock, silver wire,(with teflon coating), Elna Silmic or Cerafine for 'lytics,(power supply?) and resistive attenuation.

(Tone circuit is user's option...)

Then anodize the whole thing, and have milled aluminum anodized knobs.

Now that would be phsyco.

[Clipped and Shorn]

Mike,

sounds to me like you are having fun with those vintage Eico amps. Basically you have two seperate integrated amps with EL84 output tubes. I wonder if those use the same great output transformers as the HF-81, I would think so. Have you checked to see how similar the schematics might be? Maybe your stuff doesn't sound as bad as you describe?

-C&S

------------------

Cornwalls

currently upgrading

to all tube components

This message has been edited by Clipped and Shorn on 08-31-2002 at 11:58 PM

[mike stehr]

I have no idea Clipped, I think the OP trannies are the same, I can't say.

(Good question.)

The output circuit in the schematic, is kinda the same as the HF-81, if I recall.

I would have to look at the two, I printed both.

Here ya go, I scored a '50's era Packard Bell Televison with Phono today for 5 bucks, wierd tubes, but had a 6SN7 and 5U4GB rectifier.

The thing is huge, The parts would be pretty much useless, except maybe a few resistors, and the massive power supply trannie.

So I ripped the television unit out of it, and am going to use it for a component rack, it has tons of room with doors, and the cabinet is in good shape in spite of age, and looks cool.

It will match with the other junk furniture from the same era.

[Clipped and Shorn]

Strange that there is not much Eico available on eBay these days as there had been several months ago. Besides this "unbuilt" HF-81 there is a pair of HF-14 monoblocks.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=1376971342

Because these have a funky history ( noisy with lots of static), they might end up an inexpensive bargain for someone to play with. I'll bet someone with a a soldering iron could clean these up easily. EL84s and vintage iron, how bad could they be. Even if you didn't know anything, there are not so many parts you couldn't just upgrade ALL of them and then check the wiring for mistakes or bad solder joints and you would have them sounding as good new or better. Could the symptom " noisy with lots of static" mean the transformers might be bad? If that is the case, then, never mind.

-C&S

------------------

Cornwalls

currently upgrading

to all tube components

This message has been edited by Clipped and Shorn on 09-01-2002 at 12:44 AM

[Tom Mobley]

ripped and torn,

I was eyeballing those a little while ago. Too bad there's not more info available. What I'm wondering is exactly how a guy would hook these up as stereo. They're integrated amps, not power amps. Like from a CD player, just hook the left output to one and the right to the other? I can't think of any good reason why it wouldn't work.

Yeah, and ebay was swamped with Eico stuff a while back, but a lot of it was test gear.

Tom

[Clipped and Shorn]

kh states:

"C&S, your grasp of science and its subsequent reinterpretation via text is about as mystical as it gets."

This would appear to be a meaningless sentence containing non specific references and vague terms.

"subseqent reinterpretation via text" what does that mean?

"ps-The EICO actually has some excellent measurements for those that believe this is a valid forcast of sonics and "what sounds good." "

Right, all you have to do is go to the Eico homepage and read the original ads to get some promising specs. I never said anything to the contrary. What is this unprovoked defensiveness. You must be thinking or dreaming of past arguments with others, because I am not the source here.

You seem to want things both ways. You will mention specs when you counter someone who says an amp can somehow be beyond specs, then you will say sonics is beyond specs when someone mention specs. LOL.. Hard not to win at that.

It is difficult to continue a rational discussion if vague terminology and hypersensitive defensiveness produces unneccessary divisiveness. We need to keep things lighter around here.

You like jazz, no? The idea is to let the cats blow, have their space to stretch out, make mistakes, make an occasional revelation, and think out loud. That is the spirit. . Let it happen man. One is lucky if one can at least control things in his own living room.

-C&S

------------------

Cornwalls

currently upgrading

to all tube components

This message has been edited by Clipped and Shorn on 09-01-2002 at 03:22 AM

[Clipped and Shorn]

Tom,

Those HF-14 pair on eBay are two mono amps. The HF-12 is the integrated (the one's Mike has).

Yes, there is probably no reason why you could not hook up a CD player directly, one channel each. I happen to have a single HF-14 and I have it in my painting studio to listen to an FM tuner in mono. I have the FM tuner hooked up directly to the HF-14 with no preamp. Sounds pretty good. I think all we had to do was replace a cap or two to get the thing humfree. If those pair remain a sleeper bargain you might consider them. Since I do not have a schematic for the HF-14 on hand, I cannot tell for sure to what extent the circuit is nothing more than half of the HF-81 amp section. When I got this one it is was dirt cheap and it more than meets my needs out in the studio. If they do not remain a super bargain, I wouldn't bother. There are so many other similar possibilities out there for quick and easy.

-C&S

------------------

Cornwalls

currently upgrading

to all tube components

This message has been edited by Clipped and Shorn on 09-01-2002 at 02:54 AM

[Clipped and Shorn]

Mike,

5U4 and 6SN7 could come in handy down the road. I have been noticing a lot of old organs in the thrift stores, some have tubes, only problem is who wants to get something that big just for the tubes, and they won't sell you just the tubes because it renders the rest even more worthless than it already is. Fini has the knack for finding interesting stuff out there too. Hey, where the heck is fini these days.....maybe his logic board got fried. We really miss him and his fini humor.

-C&S

------------------

Cornwalls

currently upgrading

to all tube components

[jazman]

mdeneen,

I thought I said there was some humor in my remark, but did not go further to specify, and much may have been left to open interpretation. So, I don't know if you remember that someone called the gutting of the Dynaco "the dustpan amp". That would make C&S's HF-81 "dustpan amp 2", kind of in the naming spirit of sequels, if you undertook the project. It was not meant to be a very serious statement of thought.

What was more serious was the thought to take a more serious look at what makes it(HF-81) what it is. That really requires more serious thought and actions. If it's just a matter of assembling parts, then we could have a cottage industry going in no time. If the sound from the resulting assembly is inferior to the original, then some other factors are in play. That would be a starting point.

So, the HF-81 is not a religion or mystical object to me. I am willing to ask questions and pursue answers, and if it's just all parts, let's charge by the screwdriver twist to price the damn thing and make some bucks. We'll just attach mystical attributes to it based on the number of screwdriver twists in the marketing plan. Has anybody got anything against pursuit of more information and the possibility of making a little money?

Craig,

Whatever you say must be right, I give up.

Klipsch out.

[mobile homeless]

Christ, this is basically the same HF-81 debate from the same three people that have always been circumspect of the HF-81, regardless. If only it was JUST about the HF-81 as there is a lot going on under the table. It is tiring to say the least and not worth another 10 minutes constructing a point by point retort, which has been done numerous times in the past year or more. For anyone new, just go to the 2 Channel archives for a search to read the same banter to your heart's content. It's been done before with the same results. Why bother?

I have heard many vintage units, and think the HF-81 is a special piece sonically. Period. Almost 99.9% agree with this assessment in the more experienced tube audio dedicated boards. This place, for various reasons that are transparent to some, is a different matter. No need to go here as, once again, it is a tired debate and far beyond the actual sound of the amp. I suggest we get back to the point.

My advice to those confused by this banter is to make up your own mind. It surely is not that expensive an option, even given the inflated prices one sees on the net these days compared to days gone by.

Another option, if you are so inclined, is to wait for the output iron and power trans to come up on ebay as they do every so often (the entire trio of iron went for $75 months ago). Buy the trio (or at least the outputs) and attempt the circuit on your own with higher quality parts and without some of the options that detract such as the tone controls and switching. I plan on doing this some day as well as I have always been interested in what makes the HF-81 such a unique sounding amp, despite its pedestrian parts content. It appears to be a sum of the whole as I dont find the amp section separated from the preamp to contain the same sonics, even when run from top flight preamps. I also have never been a big proponent of tone controls or the type of parts contained in the preamp section. Unlike a host of other vintage units, it has a full triode front end. In addition, I have preferred larger octal tube based preamps such as the 6SL7/6SN7/5691/5692 over 12AU7/12AX7 variants (and most definitely over 6922). Still, as said before, the HF-81 seems to be more than the simple sum of its parts.

Dont put total trust in my ears or the ramblings of others, however. Give it a go in your own system or not. Learn something else along the way. Keep your mind open.

kh

This message has been edited by mobile homeless on 09-01-2002 at 09:00 AM

[mobile homeless]

For those interested, here is a schematic for the HF-81, see below:

My scanner is down at the moment, otherwise, I would post a complete parts list with values along with that schematic. This is very helpful for comparison.

As for the HF-14 monoblocks, these appear to be an interesting option. I talked to a guy in South Carolina that had modified his with good parts and loved them. I havent heard them however.

kh

This message has been edited by mobile homeless on 09-01-2002 at 09:11 AM

[Parrot]

Tom,

A pair of HF-14 amps would not be good for you unless you had a preamp with them. If you plugged a CD player directly into them, you'd have the full power of the amp, 12-14 watts, coming at you. And unless you were playing a really low-level CD or on inefficient speakers, you'd be in pain. If you have Klipschorns or something like that, you'd run out of the room with your hands over your ears. You'd have to have a preamp in order to control the volume.

A common cause of noise or static in integrated amps would be dirt in the volume control pot or the treble or bass pots, and that *might* be easily fixed with contact cleaner.

But since the HF-14s don't have these pots, they're only power amps, it's got to be something else. I'd get the ones up for auction only if you were willing to pay to have someone fix them for you.

(Clipped & Shorn probably got away without a preamp because his tuner doesn't have the high output of a CD player.)

This message has been edited by paulparrot on 09-01-2002 at 09:16 AM

[mobile homeless]

Paul is exactly right here. The HF-14 monoblocks are only amps and not "integrated" with preamp circuitry. One could make a simple volume pot/passive application to listen to them or use the variable output on CD players so equipped (this is usually a very cheap pot and not the best sonically). Doing either of the above would put the onus on the power supply and voltage of the CD player or source (as well as a short pair of IC to avoid rolloff).

Regardless, the HF-14 are rare birds that dont come up too often for sale.

kh

Phono Linn Sondek LP-12 Valhalla / Linn Basic Plus / Sumiko Blue Point

CD Player Rega Planet

Preamp Cary Audio SLP-70 w/Phono Modified

Amplifier Welborne Labs 2A3 Moondog Monoblocks

Cable DIYCable Superlative / Twisted Cross Connect

Speaker 1977 Klipsch Cornwall I w/Alnico & Type B Crossover

Links system one online / alternate components / Asylum Listing f>s>

This message has been edited by mobile homeless on 09-01-2002 at 09:46 AM

[Randy Bey]

Hey, did someone mention Tesla Coils?

Dr. Evermore has some in his forevertron, but he had to sign a contract with the State of Wisconsin to never connect them to an electrical circuit of any kind, they are so large and potentially dangerous!

evertron

This message has been edited by Randy Bey on 09-01-2002 at 09:38 AM

[mobile homeless]

Hey Bey, I now see where your constant never-ending preamp search has taken you. I have been saying prayers on your behalf daily, trying to include every version of God, Worldwide. Based on this last post, my efforts have largely been fruitless.

The Great Jehovah-1 of Bob Dobbs fame is needed for guidance. This is beyond mere passive vs active debate! heh....

kh

This message has been edited by mobile homeless on 09-01-2002 at 09:44 AM

[mike stehr]

I wonder how this HF-14 Auction will turn out in 3 days?

So who's gonna bid on 'em?

I could bet that one of the multisectional's is fried and makes it hum, one of them looks replaced, but it could the wrong value/voltage multisectional, who knows.

It could be a bunk tube contributing to noise, or cooked carbon comp or two, who knows.

Look at the circuit, there is nothin' there, you could replace the resistors and caps for almost nothing.

Yeah, they are monoblocks, and you would need a pre-amp, and lord knows what would be the best match for these things as far as a pre goes for today's standards.

I know, A volume pot off a CD player, or a portable CDP

is a cheesy way to go, but it's what I do, because I am a poor bastard.

If you can live with that, these HF-14's would be tube audio on the cheap!