oldson
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Post by oldson on Aug 1, 2023 20:03:26 GMT
i have an itch to try an otl amplifier without breaking the bank. just stumbled across Eufonika, a small company based in Poland eufonika.pl/index.htmlthey have an ebay shop. i have enquired about the "H5" ,of which there are 3 variants and i would like to know how they differ. they do appear to offer good value, to me. any thoughts? |
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Post by Mr Trev on Aug 2, 2023 21:15:45 GMT
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Post by lobalwarming on Aug 4, 2023 20:59:32 GMT
i have an itch to try an otl amplifier without breaking the bank. just stumbled across Eufonika, a small company based in Poland eufonika.pl/index.htmlthey have an ebay shop. i have enquired about the "H5" ,of which there are 3 variants and i would like to know how they differ. they do appear to offer good value, to me. any thoughts? Hi oldson . I bough a semi-custom H5 over a year ago. Next to the G1217 Solstice, the best value amp I've ever owned. For less than half the cost of a fully tricked out Crack, the H5 is a wonderful OTL. Quiet, well-built, with individual choke power supply for each tube section. Amazing versatility. I've had endless hours of tube rolling fun. While nominally a 6SN7/6AS7/6080 amp, it works well with the ECC81/ECC82/EC90/EC92/396A/5670 kiddies driver tubes (adapted). And 6J5/6P5/L63 twins. And 6350, 6N6P, ECC88, 6F8G, ECC31/32 and more! For outputs I've used the TS 6080s, 5998, 7236 and Bendix 6080WB, Chatham 6AS7. My fav output tubes are the low cost, but high clarity GEC CV4079 twins. If you don't want to muck around, like I do, with cap rolling, then the H5KPCU with the Miflex PIO caps is the model to get. Miflex KPCU is used for the coupling cap and output bypass cap. It's a rich, delicious, detailed combo which best reveals the H5's strengths. The basic H5 is hamstrung by the meh coupling cap. However, for low cost it can be replaced with Amtrans AMCY .1uf copper foil cap or soviet era Telfon or PIO caps. A second pair of Amtrans can be used to bypass the output electrolytic. Or like me you can order your H5 with dangly cap leads and dive into the crazy pool of cap rolling. Almost as much fun as tube rolling, and nearly as cheap. ;-) The H5DS offers 6V/12V heater supply for the driver. Variable heater option can be added to the H5KPCU model. If you have a number of 12SN7s then it makes sense to get that option. Like I didn't, instead spend more money on external heater adapters. However, can you ever have too many tube adapters? No, no, you cannot. PM me for more info and crazy tube/cap rolling ideas/mayhem. |
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oldson
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Post by oldson on Aug 5, 2023 13:02:17 GMT
i have an itch to try an otl amplifier without breaking the bank. just stumbled across Eufonika, a small company based in Poland eufonika.pl/index.htmlthey have an ebay shop. i have enquired about the "H5" ,of which there are 3 variants and i would like to know how they differ. they do appear to offer good value, to me. any thoughts? Hi oldson . I bough a semi-custom H5 over a year ago. Next to the G1217 Solstice, the best value amp I've ever owned. For less than half the cost of a fully tricked out Crack, the H5 is a wonderful OTL. Quiet, well-built, with individual choke power supply for each tube section. Amazing versatility. I've had endless hours of tube rolling fun. While nominally a 6SN7/6AS7/6080 amp, it works well with the ECC81/ECC82/EC90/EC92/396A/5670 kiddies driver tubes (adapted). And 6J5/6P5/L63 twins. And 6350, 6N6P, ECC88, 6F8G, ECC31/32 and more! For outputs I've used the TS 6080s, 5998, 7236 and Bendix 6080WB, Chatham 6AS7. My fav output tubes are the low cost, but high clarity GEC CV4079 twins. If you don't want to muck around, like I do, with cap rolling, then the H5KPCU with the Miflex PIO caps is the model to get. Miflex KPCU is used for the coupling cap and output bypass cap. It's a rich, delicious, detailed combo which best reveals the H5's strengths. The basic H5 is hamstrung by the meh coupling cap. However, for low cost it can be replaced with Amtrans AMCY .1uf copper foil cap or soviet era Telfon or PIO caps. A second pair of Amtrans can be used to bypass the output electrolytic. Or like me you can order your H5 with dangly cap leads and dive into the crazy pool of cap rolling. Almost as much fun as tube rolling, and nearly as cheap. ;-) The H5DS offers 6V/12V heater supply for the driver. Variable heater option can be added to the H5KPCU model. If you have a number of 12SN7s then it makes sense to get that option. Like I didn't, instead spend more money on external heater adapters. However, can you ever have too many tube adapters? No, no, you cannot. PM me for more info and crazy tube/cap rolling ideas/mayhem. hi mate,and thanks for the reply regarding the different H5 models. i had been trying to get this info from Eufonica, without much success. i do have a chance of a very cheap Brocksieper Earmax amp, but if that falls through i will almost certainly go the H5 route. i will tap you up for more info if this happens. cheers |
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Post by lobalwarming on Aug 5, 2023 23:37:24 GMT
hi mate,and thanks for the reply regarding the different H5 models. i had been trying to get this info from Eufonica, without much success. i do have a chance of a very cheap Brocksieper Earmax amp, but if that falls through i will almost certainly go the H5 route. i will tap you up for more info if this happens. cheers I would caution you about that old amp. If it cost less than $25 it might make an interesting conversation piece about one of the worst examples of an OTL amp.  It uses a pair of ECC88 as outputs. It has an output impedance of about 80ohms. Which may seem high, but is really good for a pair of small signal kiddie's tubes. Uncertain how much negative feedback was employed to get below 100 ohms - although the push/pull design would help - but push/pull means it is not a true Class A design. The Pro version has a max output of 150mW. All those horrid design compromises isn't the worst part of it tho. The worst part, for me, is the inability to roll output tubes (or drivers). Perhaps you'll get lucky and discover it's a revelation and your search for thermionic bliss is complete. More likely you'll find it is a low resolution, high distortion device that puts you off OTLs forever. That would be unfortunate. I strongly advise skipping this little piece of audio novelty. Get the H5. It will give you a much better sonic overview of OTL design and the chance to find the output and driver tubes combos that you most enjoy. |
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oldson
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Post by oldson on Aug 6, 2023 19:57:18 GMT
I would caution you about that old amp. If it cost less than $25 it might make an interesting conversation piece about one of the worst examples of an OTL amp. It uses a pair of ECC88 as outputs. It has an output impedance of about 80ohms. Which may seem high, but is really good for a pair of small signal kiddie's tubes. Uncertain how much negative feedback was employed to get below 100 ohms - although the push/pull design would help - but push/pull means it is not a true Class A design. The Pro version has a max output of 150mW. All those horrid design compromises isn't the worst part of it tho. The worst part, for me, is the inability to roll output tubes (or drivers). Perhaps you'll get lucky and discover it's a revelation and your search for thermionic bliss is complete. More likely you'll find it is a low resolution, high distortion device that puts you off OTLs forever. That would be unfortunate. I strongly advise skipping this little piece of audio novelty. Get the H5. It will give you a much better sonic overview of OTL design and the chance to find the output and driver tubes combos that you most enjoy. i only had a short time with the Earmax as it had a fault. i thought it sounded pretty good, but if the Eufonika amp is far better , then i am interested for sure. i did browse through the thread on head-fi and was interested at the comments made by someone who had both the earmax and h5. i got the impression he didnt think there was a great difference in performance. i think he was known as "grumpy old man" or something similar. |
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oldson
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Post by oldson on Aug 6, 2023 20:13:41 GMT
whatever i get could see me parting with the Violectric.
really good amp but i prefer my Ember
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Post by lobalwarming on Aug 7, 2023 21:25:34 GMT
whatever i get could see me parting with the Violectric. really good amp but i prefer my Ember If you felt the Earwax was pretty good, expect you will be gobsmacked by the H5.  After spending much time (and some money) on tube rolling. The tubes you are using now with your Ember can be used with the H5 as drivers. Just leaves the output tubes to drain your bank account.  Although if you avoid the over-hyped, over-priced ones like GEC 6AS7 and TS 5998, you won't need to spend too much to cover the tonal buffet. What flavour combo you enjoy most is for you alone to discover. |
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oldson
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Post by oldson on Aug 9, 2023 20:18:05 GMT
one thing that would tip the scales heavily in favour of the Eufonika over the Earmax is the pre-amp function.
my problem is that i have recently traded in my old Marantz integrated for a Rega Elex-r.
the Marantz did have a "direct power amp" input where the Rega does not.
i dont want to "double amp" the signal from my source.
however, i have read that using an external pre-amp into an integrated amp is fine providing the integrated's pre-amp section is "passive". (which it is on my Rega).
just not sure whether this is actually true?
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Post by lobalwarming on Aug 10, 2023 22:54:25 GMT
Elex-R does claim to have a passive preamp section. The other thing that scales heavily in favour of the Eufonika over the Earmax... is the sound. H5 is on another level. The richer, more detailed, more spacious level. |
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oldson
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Post by oldson on Aug 11, 2023 20:37:52 GMT
the pre-amp option into my Elex-r is a non starter i have concluded, a buffer would be my preferred option maybe in the future.
i certainly wont be swapping out the Elex-r anytime soon.
the Earmax is off the menu now as far too expensive, considering its age.
so i am close to ordering the H5, but still researching the option of a transformer coupled unit, to accommodate more headphones
White bird audio master is interesting me too
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Post by lobalwarming on Aug 13, 2023 8:00:41 GMT
Wieslaw could build a custom transformer output amp for you. He has in the past. However, you still wouldn't know what a good OTL sounds like. Could ask him to build an amp with switchable trafo/OTL option. He's just crazy enough to enjoy the challenge. You might as well. Happy thermionic searching! |
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oldson
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Post by oldson on Aug 15, 2023 12:49:20 GMT
just ordered the H5KPCU
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Post by lobalwarming on Sept 12, 2023 21:15:10 GMT
Excellent choice! Hope you enjoy it. Great pairing with the 1990. With all the money you've saved (for retirement) you can now spend on tube rolling! |
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oldson
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Post by oldson on Sept 14, 2023 17:18:16 GMT
hopefully one day i will stop headphone rolling!!
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