Eico tended to use a lot of ceramic disk caps in places they should not have- such as coupling caps. But their transformers were pretty good. So if you replaced the coupling caps (and of course have the power supplies rebuilt) their stuff sounds just fine.
I rebuilt one of their preamps and ran it for years, although I ran it with an external supply.
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great buddy of mine owns 3-5 of them at any given time..w Revel 2 something be.....very very nice sound.......stop debating and listen !!!!! |
I have a Sam Kim complete rebuild Heath Kit 151 that is simply outstanding. Using only the chassis and transformers Sam rebuilts the entire amp from the ground up.
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Nice job pokee great read |
The sole reason why I am a long time Agon member, musicophile and gear nerd is because, beginning early in 1967, I moved to Brookline, MA, and my new and best friend's dad had an Eico HF81 fed with a Dual table powering AR 2s. Over the next couple of years I heard on that system, in a large living room, for the first time, just-released Hendrix, Beatles, Tull, Airplane, Stones, Janis, Who, Zep, Taylor and others. That system filled and energized that room and I will never forget it.
If the Eico HF81 had anything to do with, yeah, it's a good one. |
Nice write-up, Pokee. Not quite an 81 but I have 2 pairs of HF35s. 35watt mono amps. One is a Stu Remmington rebuild with chokes and fixed bias. They are glorious.
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I'm not sure if it's bad etiquette to comment on a thread that has been sleeping for over 5 years but having recently acquired an HF-81 which I am currently restoring I thought I should share some of my experiences. A little background: I have been in the industry for several decades, have worked on and restored many amps and have designed components while working for Mark Levinson (the man), Speakerlab, Antique Sound and others. I believe I have a knack for getting real musicality out of a circuit design and likewise I try to do the same when I restore old gear. The Eico came to me in nearly original condition and quite well preserved. I replaced the electrolytics first and foremost using Elna Cerafine and a JJ multisection cap for which I had to modify the opening on the chassis. I also replaced all tubes with new production JJ and Mullard. I used Cornell Dubilier as DC coupling caps to the output pentodes and Mundorf Supreme in the first two stages. Next phase will be to carefully replace some of the Allen Bradly resistors that have drifted a bit beyond acceptable limits but boy does this thing sound good. As mentioned before the magic is in the output transformers and of course the circuit which is interesting to say the least. I have left the tone circuit intact but bypassed the balance or "focus". Here's an interesting fact I don't hear much about- these OT's are wound for 16 and 32 ohm outputs. In my mind this may be part of what makes the magic as the secondary impedance is rather high- much higher than in other output transformers. The price of these units has gone through the roof but I have to say so far it's worth it. For a tweaker like me it's a great project. Nice to read some insights here. |
Amhifi, I think its pretty darn cool that your Eico is associated one way or another with Neil Young. You truly do have a very special piece of gear. |
I have an HF81 which was restored and modified by Sam's Audio.
He changed the mode of operation to triode, I believe, so it now outputs just 7 watts per channel instead of 14 watts, but it sounds amazing.
For sometime I was running it with a pair of Wilson Audio Duettes - not a speaker most would recommend for this amp, but the sound was glorious! Even large scale symphonic works sounded great at moderate levels. Visitors couldn't believe they were hearing just 7 watts!
Lately I have had this amp driving a pair of GoldenEar Technology Triton 2 Floorstanding models which have their own amps for the woofer sections. Since the HF81 is only powering the mids and highs, this is a perfect application for it and the result is terrific.
I don't imagine I will ever recoup my $ 2000+ investment, but it is a experience worth having.
It may be of interest to know that this particular amp was originally used in the sound system of a community club in Winnipeg where Neil Young grew up. Neil's band would practice at this club using the sound system with this amp. A volunteer at the club acquired the amp when the sound system was upgraded years later and I purchased it from his son several years ago.
Dennis Penner
Winnipeg Canada |
Yes, it really is that good. Its basic design was conceived during a time that tubes ruled and provided a very good foundation for superb sound but many of it's older parts need to be upgraded to realize its full potential. |
Can't speak for the HF81 but my HF35 6L6GC monos with new caps are outstanding. Lovely musicality, timbre, and delicacy and decent clean articulate bass. |
I have one mated with some university 315c (like Altec 604s)... Doesn't get too much better and if it does one must ask themselves at what cost... |
I had one for awhile, paired with Klipsch Cornwalls. Very open sound, but not enough "weight" in comparison to my Decware and Cayin integrateds. The phono section hums a lot too. I ended up trading it to a friend for EI KT90 quad, and other goodies.
Mike |
I urge everyone who is interested in the HF-81 to try Pilot 602 receiver which has outraging bass and presence, at least on my Tannoy Arden II, MG III LZ, and even the low efficiency (read: 81.5dB/1 watt) Celestion SL700.
These two EL84 PP amps seem to have comparable output transformers and I suppose their sound should be similar. Not the case, to me at least. The Pilot 602 doesn't even sound close to the Fisher SA-16, a console amp from the 50's. The Fisher has thinner bass, though. |
Very good sounding small amp. If you can find a vintage dual concentric Tannoy speakers or Altec 604 you will be suprised how this little amp sounds. |
>>your 400.00 little amp will kill any solid state unit over 1000.00<<
I want to make sure what you wrote is what you meant. Your position is this amplifier will "kill" any solid state amplifier over $1000. Is that correct? |
>>But, in the end your 400.00 little amp will kill any solid state unit over 1000.00<<
ROTFLMAO |
As with all tube gear with a transformer output the transformer is really important. EICO wound some excellent sounding ones. you also need to remember that in the 60s tube audio was state of the art so circuits and components were pretty much dialed in. So, with the plethora of tube units available at the time your dollar would buy better chassis or cosmetics or assembly. Fisher, I feel , was the leader in lower power units with 6bq5 and 7591 and 7868 output tubes. HH Scott also had some excellent sounding 6bq5 and 7591 amps but i am not so fond of the scott since the chassis is small and components and wiring is really tight. When you have a problem it can be challenging doing repairs. Next are the eico, heathkit , allied , knight , lafayette, sherwood, etc... I have listened to almost all of these and they are all amazingly good sounding if in good working condition. Which, is the problem,since you are dealing with equipment that is over 40 years old if the unit was sitting around for over 5 years without being used then there could be problems and you need to expect that and unless you are willing to do a rebuild yourself you need to budget for a rebuild.
But, in the end your 400.00 little amp will kill any solid state unit over 1000.00 and sound the same or better than any amp around 1500.00.
BTW, i have rebuilt eico hf 12 (3), st 70 (3 of them), 4 fishers and 3 scotts, lafayette, etc... and Eico is one of my favorites because. large chassis, point to point wiring, excellent component layout, conservative operating conditions, excellent sounding circuits, and superb sounding transformers. I am rebuilding 2 eico hf 32 which are like hf12 on steroids! they use 4 el84 in push pull parallel for 32 watts of real power. the transformers are huge bigger than dynaco st70. These units sound sweet with bass that you can feel. Big fat thumping bass. I have just finished rebuilding the power supply and will be putting them up for sale. Contact me if you are interested. thankyou, PRIMOTUBES |
In my experience, it's better than Jolida 302B or Mcintosh MC 240. I'm getting another Eico on ebay soon. |
I had Ryan Inman of Hot Glass Audio do it. Had the unit sent directly to him after auction. He actually saved me $100 on the Eico tuner that I bought with it...seller said it was working, Ryan said it had never worked it recent history. Seller grumbled something about "shipping damage" but ponied up $100 and had the unit picked up. Restoration was functional, not cosmetic, and the unit sounds fantastic! |
You can reference my Fisher 500c article (sterophile.com, historical) where I mention a guy in HK who makes and sells banana/lug adaptors.
Or for a cheap fix go to Home Depot elctronics section and look for lugs that have barrel screws about the size of banana female.
Peter B. |
Srayle,
Who did you have restore the HF-81 |
How do owners connect modern spaded speaker cables on that vintage terminal strip? Is making up an adapter necessary? It seems to me that modern spades could short out to adjacent terminals. |
I just received an HF-81 that I bought and had restored. I've not owned any vintage equipment before, but I must say, I am amazed by the sound. Terrific musicality, one listens to the music more than the equipment. It actually competes with my Fi
2a3 monoblocks! It's not much to look at, but to listen to...wow! |
Baranyi, Bozaks are simply very unique and a MUST listen.But once you listen you'll find they are a MUST own. Tha Grands or the Symphony but if you don't have the space, go for the 302a which I feel image better. Have fun! |
Peter,
Thanks for making an appearance on this thread. Even though I now run Apogee Scintillas I used to run vintage speakers such as JBL Hartsfields with Vintage Marantz tube gear. The sound was quite good in the midrange but not very extended at frequency extremes. I used to be a collector of vintage audio. I never gave the Eico's a second look which was obviously an oversight on my part. I have listened to many vintage speakers but have not heard the Bozaks. Are there any other gems that you are using at present? |
I suspect you have have not heard one of these 6bq5s vintage amps on efficient speakers.
Don't shoot the messenger until the message gets delivered :)
I had a jaded x-reviewer over who thought this was all total nonsense. He was floored when he heard the Eico over the Bozak Concert Grands. He is a Krell man and thought the sound was in the same league of his $50,000 system.
Again, don't shoot the messenger!
Peter B. |
The Eico was not modified. Only restored. The volume control had to be rebuilt because of bad sweeper pad. At low volumes the left channel was down 20db.
Sam also resoldered everything.
I have heard four of these and my mint unrestored one sounded great although it was soft in the bass---it needed electrolytics. The two Sam did are tighter and more open on top. These amps are really really good.
Peter Breuninger
Stereophile Contributing Editor |
I think the Eico HF-81 has incredible musicality. If you allow yourself to have an open mind see how you just widely smile hearing real acoustic instruments and voice on this amp played through todays better speakers (use ones with an easy load for amp with efficiencies over 90db/m). Some complex musical crescendo at higher volumes, for example, get blurred but these nits aside check the threads on audiogon and elsewhere about this low parts quality but timeless circuit amp. These accolades came long before the Stereophile review. BTW: The mono versions of this amp HF-12 are a super value and give the benefits of dual mono-design. |
hi Lolo
from page 159 of June Stereophile,
"The EICO was restored by Sam Kim of Sam's Audio Labs in Montreal,Canada. The work done included replacing the output and filtering capacitors and all out of tolerence resistors, rebuilding the volumn control, rewiring the undercarriage and resoldering every eonnection."
The author goes on but nowhere does he mention modifying the circuit. As far as I can tell from reading this it was a complete restoration.
Yes I have a restored EICO HF-81 and it's a great amp. I paid a total of 600 dollars for it. In spite of JA's measurements it sounds great ( much like SET amps )!! For copmparison I have tube amps from Cary Audio, Wright Sound Labs and Conrad Johnson.
For the price you pay it's unbeatable and can keep up with many " state of the art " modern amps at a fraction of the cost.
All I can say is get one and listen to it, you will be astounded and wonder why you spend so much on the new stuff.
Larry |
Once again JA's measurements call into question the hearing & judgement of his reviewers. I go the opposite way on this one. Once again whatever JA is meausuring has little correlation to how an amp will sound. After all, the BPC (mostly silver now) from Best Buy all have better measurements than that EICO. I'll take the EICO anyday & everyday. |
The hf-81 in Stereophile had not only a COMPLETE ground up restoration, but had circuit tweaks. It is the pinnacle of what this little int. tube amp can be. For the majority of us, replacement of caps, resistors, upgrading tubes and vibration/isolation devices is as far as it goes.
That is how far I went with rebuilding/upgrading my hf-81 and it sounds outstanding. One thing about the hf-81 is that they have excellent output transformers but can be expensive if they need to be replaced.
I wouldn't spend $2K rebuilding/upgrading any hf-81. I would recommend finding one that is in good condition and doing a partial rebuild/upgrade that would probably cost in the neighborhood of $200-$400. An hf-81 is going to cost you more these days due to the glowing article but I bet you could still find one in the $150-$250 area. |
My EICO was rebuilt with new caps and resistors for about 500 dollars. |
Having the right speakers is critical, although it's really pretty gutsy. But it sounds its best with pretty efficient speakers. Mine are powering a pair of moderately efficient PSB 800's and sounding good.
I've actually had two of these. The first HF81 I got from my uncle, who bought it factory-wired in 1958-9. When I got it, it hadn't been played in 20 years. It had leaky caps and a loose power supply (bolts needed tightening). I replaced the coupling caps with russion PIO's. The cathode bypass caps on the EL84 output tubes were gone too, replace with Sprague atoms. And the plate resistors had all drifted pretty far off spec, replaced with carbon films. that was all last year. this year I put in new power supply caps, which tightened up the bass considerably.
No, it's not a modern amp (the Manley Stingray is a lot more extended and clean-sounding, for instance), but it's lovely to listen to as a second (bedroom?) system. I've been through a lot of stuff, and this one's a keeper. Yes, the parts are crap. Yes, it looks like shit. It sounds WORSE if you upgrade all the parts (heard one with all audiophile-approved parts--my mostly original one with all the crummy mica caps sounds much better). I guess it was voiced with the components of the day. Yet somehow it all seems to work together.
A lot of them (most?) were kits, many badly assembled, with cold solder joints and mis-wired circuits. You can certainly find really cruddy-sounding ones out there. The last one I got was less than $200, and required less than $150 to replace out-of-spec parts, plus another $150 in tubes. But the result was/is a terrific sounding amp. Go figure. I gave it to my neighbor after she spent a week dog-sitting. She loves it, and I'm pleased every time I go over to visit and hear it.
I wouldn't build my main system around one, but it's certainly more musical than a lot of stuff being sold today as high-end, that deliver detail but lose the magic. Hard to beat the bang for the buck IMHO.
HTH! |
Someone always has to dispute statements So , Larry510 sorry to have to tell you your wrong --- Sam's claim to fame is that he "completely redesigns" and even "fixes " design flaws in the original vintage gear just using the original trans and the chassis and case-which is what he did to the hf-81 reviewed by Peter Breuninger. Read page 159 in Stereophile. That ain't no basic restoration if you ask me. But you can ask Sam himself. Here's his # call him 514 485 3587. I've heard several of his "restorations" of vintage amps etc. They ALL sound great but not very close to the originals. None the less , the ORIGINAL 81 does sound good. BTW Larry510 , did you ever hear Sam's or an original hf-81? Curious to hear your impressions. |
Stereophile made it seem like this amp was one of the best ever. I have had loads of Marantz and Mcintosh and they were very good and now own Dynaco mk4's. I never really bothered with Eico gear. Could it really be worth $2000 to have this amp upgraded? Bob |
hi,
"05-25-06: Lolo
Well,it does sound good in it's original condition. The one reviewed in Stereophile was HEAVILY modified".
From reading the article I believe it was restored and not modified.
Larry |
Well,it does sound good in it's original condition. The one reviewed in Stereophile was HEAVILY modified by Sam's Audio Labs from Canada. So the chances of the original sounding as good are very unlikely. Is the original 81 better than moderm amps? Most likely not in most cases but it does sound real good especially for the price. BTW- the hf 12 and the other EICOs also sound very good. I love the ST 70 int. I have a hf 12 (mono) and a Motorola (mono) I found in a pile of older amps in my basement and decided to use them to power my ATOMS. It's laughable how good they sound even as mismatched as they are. Sometimes I feel some what ripped off with modern gear- very high priced compared to some of these (originial unmodified) vintage gems. I've put togerther many systems for less than $50 that can easily outperform systems priced at $5K BUT you have to maintain the old stuff. If you can get an EICO for under $50 , do it. It's worth hearing what goodvintage gear can sound like. More than that I wouldn't |
I recently bought an EICO hf-81 and had it rebuilt with new caps, resistors and other components that were either bad or out of tolerance. I have also updated the tubes with decent quality tubes. With that being said, my impressions are based on my limited audio experience.
The hf-81 used in conjunction with the right speakers, in my case very efficient Klipsch speakers, sounds awesome. I say the right speakers, only because of the limited output of 14watts per channel. I would also like to add that I have completely upgraded the speaker crossover networks, so they are very dynamic and detailed without the brightness that has been associated with Klipsch speakers.
I have listened to some high-end systems at hi-fi audio shops and have had the opportunity to own equipment such as Krell, Plinius, Sunfire and YBA. My hf-81 every bit as good, if not better, than some of the other equipment that I've owned. The musicality, warmth, smoothness and detail retrival is just amazing. The article, IMHO, accurately described what the EICO hf-81 is capable of. The only drawback of the hf-81 is the 14watts per channel output. Other than that, this little tube integrated is absolutely amazing.
It's not the "be all - end all" but it can easily compete with other pieces of equipment. When you look at the price point of this unit, it's hard to argue the tremendous value. I have not heard some of the others from that era like the Scott, Dynaco, Heathkit or Fisher. However, the way my hf-81 sounds, I perfectly satisfied that I have something that is one othe best. |
i have a HF-81 and yes it sounds great. I have three other tube amps from Cary, Wright Sound Lab and Conrad Johnson and the little EICO gives up nothing. A bargain if you can find one. At 14 watts a side you need efficient speakers.
Larry |
Porziob writes: Once again JA's measurements call into question the hearing & judgement of his reviewers. Agreed. The most interesting thing about this episode. Regards, |
It's funny. I've never heard this unit, but in EICO's heyday in the mid 60's I was into amateur radio. EICO was one of many suppliers of kits to this market. Their stuff included transmitters, receivers, and test gear (oscilloscopes, voltmeters, etc). I owned one of their scopes.
EICO was considered a kind of second rate supplier of cheap low quality gear at the time. If you wanted a kit and had money Heath was considered much better.
It's interesting to hear this amplifier praised so highly in Stereophile. I guess I'm just prejudiced from experience. |
Yep. I, for one, have never understood the mystique & panache some audiphiles attribute to Eico. This is another hit on Stereophile`s ever diminishing credibility. In it`s day (long gone), Eico was merely cheap, inexpensive & decent gear (no more, no less). For anyone considering himself an audiophile to tout Eico as a giant killer & incredible is laughable & borders on the absurd. Absurdity abounds in this hobby. Once again JA`s measurements call into question the hearing & judgement of his reviewers. |
There's nothing unique with the circuitry- it's all the sound of the output transformers. They don't look like anything special either, and their low end is lacking, but wow, what a lively, unrestricted sound they have. |
