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Post by PinkFloyd on Jan 20, 2010 21:31:16 GMT
I've always wanted one of these and, thanks to Stuart (Gaudixman), there is one winging it's way across to me as we speak Has anyone here got experience of this amp? All I know about it is it takes ECL83 valves.... I have managed to source brand new Mullard (in original cartons) for £5 per pair so she's not going to be expensive to feed I believe Stuart has fitted some tasty parts to her and I hope he chips into this thread once I start messing about with the amp..... Anyways, any info appreciated. Mike.
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Post by guadixman on Jan 20, 2010 23:41:04 GMT
Hi Mike, that's a very good price indeed for ECL83s . I see that WD are charging £14.99 per piece - OUCH.
I have said that I think it's crazy to use expensive attenuators if you have an Alps Blue and shunt with naked Vishay Z foils. As Mike will find it comes with I think 47K Rikens. I've always thought that shunting a pot allows everyone to add their own flavour or not as I choose by using the neutral Z foils - you makes yer choice.
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Post by PinkFloyd on Jan 26, 2010 21:35:39 GMT
The WAD HD-83 arrived yesterday and I was shocked by the size (and weight) of it..... a bit of a beast compared to the likes of an Aune or a X-Can V3! I had a brief listen this morning and it didn't do much for me so I took it out to the workshop for a closer look..... the pot connections were VERY tired and just touching one of the wires with my finger caused it to part company so I totally rewired the pot with Evolution OFC pro cable. (shielded at the input using the drain wire but not connected at the pot / if that makes any sense ) Brought her back inside, had a listen, and WOW! this is one seriously nice sounding amp.... by far the best I have heard in many a good year... it's ballsy, it's bassy and the tone is beautifully mellifluous and euphonic.... "high end" is a term I hate using but, this sounds really high end I'm going to rewire the entire shebang, the guy who put it together (not Stuart) was less than competent with a soldering iron and I feel that even more performance can be squeezed out of her with a rewire / resolder. I don't have the manual for this amp so if any of you have one it would be nice to have a look I will update this thread with all the work I do to the amp and, hopefully, it will be of interest to other HD-83 owners. Listening, as I type and the SQ can best be described as "luxurious".... silky smooth with bass to die for.... the signature of the Mullard ECL83 is just sublime.... this is a true "tubey" tone and anyone who reckons valves are redundant has obviously never heard what a good valve amp can do.... I'm off to rediscover all my favourite albums Talking of valves, I've got a truckload of "never seen the light of day" Mullard ECL83, not only in original cartons but also complete with their original sleeves...... some with 14/6 stamped on them (14 shillings and six pence) and others with £0.75 pence stamped on them (which equates to 14/6 in old money) so I'm good to go with Mullards for many many years...... it's a nice feeling thinking back to the time when Mullard was a world leader in valve technology and even better putting these "never seen the light of day" valves into service in 2010..... awesome! I took a few snaps of the HD-83 when I was out on the workshop, I will get better quality shots next time I'm under the bonnet but, for the time being..... Look how tiny the Aune is in comparison
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leo
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Post by leo on Jan 26, 2010 22:55:58 GMT
Nice, proper valve voltages eh So is the pot still wired as a shunt or you wired it back up as normal?
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Post by PinkFloyd on Jan 26, 2010 22:56:27 GMT
This amp is just AWESOME! I can't believe I missed this one ;D
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Post by PinkFloyd on Jan 26, 2010 23:01:41 GMT
Nice, proper valve voltages eh So is the pot still wired as a shunt or you wired it back up as normal? Still wired as a shunt Leo...... I've got a couple of stepped attenuators going to waste so will fit one of them next time I'm under the hood. Have you tried one of these? Bloody incredible SQ! Mike.
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leo
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Post by leo on Jan 26, 2010 23:23:02 GMT
Nice, proper valve voltages eh So is the pot still wired as a shunt or you wired it back up as normal? Still wired as a shunt Leo...... I've got a couple of stepped attenuators going to waste so will fit one of them next time I'm under the hood. Have you tried one of these? Bloody incredible SQ! Mike. I've only heard one briefly a few years ago, nice piece of kit, a bit different to the low voltage valve based HA's, this one has output transformers too
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Post by PinkFloyd on Jan 26, 2010 23:38:53 GMT
Still wired as a shunt Leo...... I've got a couple of stepped attenuators going to waste so will fit one of them next time I'm under the hood. Have you tried one of these? Bloody incredible SQ! Mike. I've only heard one briefly a few years ago, nice piece of kit, a bit different to the low voltage valve based HA's, this one has output transformers too Give me time to rewire it and I'll send it to you for a listen.... it is a seriously nice piece of "kit"
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Post by guadixman on Jan 26, 2010 23:53:50 GMT
Bugger it, I should have done what Mike has done. I changed the caps and and diodes for quality ones and shunted it but this was like about 8 years ago when I did'nt think (received wisdom/bullshit) that wiring made a difference - Ill punch the lights out if I personally meet face to face the next person that says wiring does'nt make any real difference.
Mike remove the shunt resistors and tell me what you think. Right now I'll say that shunting beats useing atts. The resistors are Rikens - change them for Naked Z foils - and go straight to aural heaven.
A complete rewire is what I suggested to mike via PMs. Also Mike think about removing the mains wire from inside the chassis using an external IEC.
Well like Mike says - valves are'nt dead.
Those RIFA caps are now NOS, the Silmics are good and all this bullshit about Black Gates - the bass response is far better using Silmics.
I now would never use carbons resistors again, so I'd change all of those as well.
How many resistors are in the signal path Mike, splash out and change those for Z foils.
World-Designs changed the layout for the Mk11 to make it look better but it is'nt.
Now if you can change the 83s for 6SN7 or 6F8Gs you will go straight to Nirvana none stop but they have to be the right ones.
Anyway enjoy Mike.
PS when I find the manuals not only for the h/amp - I've mislaid all my manuals that's what hapens when yopu move I shall send it on or alternatively take a look on WD it maybe available there.
Saludos - Stuart
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Post by guadixman on Jan 27, 2010 10:40:10 GMT
I'd like everyone to know, if they don't already (which they probably do) that Mike is, to use an out-of-date expression - a man of honour. He has offered to return it to me - no way a deal is a deal and that's it.
Now to a lot of modern shits it has no value at all and neither do they but to me this characteristic is beyond price.
Mike and I did a lot of PMing late last night and he is insisting on paying nearly double what I asked, I have agreed but only on one condition and he knows what that is.
He runs a virtually unique forum in that I hav'nt seen a single threadcrapper appear to pollute threads and I can well understand why Rick42 exited Head-fi.
Needed to say that - now back to the business in hand.
Mike, rewiring and resoldering make absolute common sense and next?
I suggested changing the Txs. The PSU is so important to any piece of gear - The PSU caps are good and I don't think they need changing unless you can source a pair of Philips LL caps to change for the BC ones. The RIFA 100uF is excellant and IMO should stay.
Until I can find the manual I can't say what PSU resistors are but Mills are superb and I now would'nt use any other. I've already been banging on about using Z foils in the signal path and most importantly for shunting.
I bought the original Lehman phono stage which came in a steel box, unquestionably removing the top makes a huge difference to the sound - have you tried playing it without the lid Mike - it's worth a try. Ultimately I reckon (if you are going to keep it) replacing with an alu box would be the way to go.
A good quality mains Tx should be a worthwhile investment again WAD always used stuff that was a small and as cheap as they could get away with - down to a price and not up to a standard.
The coupling caps I fitted are Dynamicap, I can't remember the value but here is where personal taste comes in and I'm still waiting for an answer about if all wiring sounds the same then all caps of the same value/voltage must as well otherwise the first statement is pure bullshit.
These are the only caps in the signal path so are an integral part of the sound - I can think of Ven Haus Teflons/ Mundorf silver in oil or my hand made silver foil Dutch ones, which can only be had by a personal visit to a shop in Groningen but that's not a problem as my mate Harry would be willing to do.
I'm sure that srtipping out the wires to the o/put txs will bring even better sound.
Enough for now as Mike is enjoying all the distortion of those outdated valves - take not SS heads.
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Post by PinkFloyd on Jan 27, 2010 21:19:00 GMT
Stuart, As nice as your mains cable was I just HATE fixed "snakes" hanging out the back of my equipment so it was time for a bit of my least favourite thing........ "metalwork" Chopped off the snake and made a hole: Filled that hole: Fitted an "across the line" 470nF EVOX class X2 suppression cap (will be fitting class Y2 between line and earth next): Wired up using ALPHA 600V tinned copper conductor wire: Fitted a 275V EPCOS MOV: And a "mama honking" ferrite core (epoxy glued into position). : Nothing fancy, all simple stuff. There was a very slight hum before I did this, it is now totally silent so I am pretty happy with the results. I'll be removing the board this weekend and will rewire / resolder all the joints. I'm also going to remove the Dynamicaps and replace with smaller EVOX types.... I'm not a great believer in fitting oversized caps with lots of "spare" lead kicking about.... (inductance / RFI city) I'm also going to replace the 400V / 150uF RIFA 'lytic with 400V / 100uF..... I'm not sure what "brand" I'll use yet, I'll see what I have. Not keen on those headphone sockets either, will be replacing with one of these: They are lovely and smooth in operation and the contacts are far superior to the "25 pence a pop" thing that came supplied with the WAD kit. Anyways, I'm really enjoying the sound of the amp, thank you After a few more hours under the bonnet I hope it will become my "reference" amp I will keep this thread updated and, if there's anybody out there with any knowledge of this amp please do chip in. Mike.
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bullpup
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Post by bullpup on Jan 28, 2010 12:28:55 GMT
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Post by guadixman on Jan 29, 2010 14:28:13 GMT
Mike, you did'nt read my post, that was exactly what I suggested. Have you tried removing the shunt resistors?
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Post by PinkFloyd on Jan 29, 2010 14:55:28 GMT
Mike, you did'nt read my post, that was exactly what I suggested. Have you tried removing the shunt resistors? I haven't had time yet Stuart but will try removing them when I take the board out. It's a pretty strange board layout isn't it? All the grounding points bang in the middle of the two 220nF caps. the transformer inputs almost inaccessible unless you have a soldering iron shaped like a hook, and the board inputs situated directly under the pot.... not exactly a lot of space to maneuver in there As I don't have a wiring diagram I'll take some pics before I strip the board out for an overhaul so I know where everything goes when I reassemble it Have ordered a Philips 450uF / 100uF cap and will see how it compares to the 150uF Rifa cap. Mike.
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bullpup
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Post by bullpup on Jan 29, 2010 20:31:14 GMT
Circuit diagram in my post Mike.
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Post by guadixman on Jan 30, 2010 18:04:09 GMT
Mike, I don't know how long it will be before I attempt to turn the Bada into a low power amp but it has really cheap h/phone sockets.
What are the dimensions. The Bada rather handily has two h/phone sockets so we can both enjoy listening to music and practising our French together.
Available depth 1inch/25mm/available width 5/8 inch/15mm If this married with the dimensions of your type, could you let me know where I can purchase the same.
Re. the Dynamicaps if you did'nt notice any interference, surely that's not a reason to change them is it. If you want a small cap try an ERSE - bloody marvellous.
As you've put an IEC at the back why not remove all mains wiring from inside the chassis and fit an on/off switch at the back?
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Post by PinkFloyd on Jan 30, 2010 22:44:58 GMT
Hi Stuart, Finally got the board out on the bench (thanks bullpup for the diagram) and have decided to keep it "simple".... ie: use what I have. I am going for a total re-cap, given the age of the thing and will not be fitting humongous "boutique" caps. 100uF will be Panasonic FC, 470uF / 35 will be Panasonic NHG, 100uF, 470uF / 450V will be EPCOS, 100uF / 450V will also be EPCOS types..... the 220nF / 250V will be Evox PHE 426. Silly to buy in more caps when I have all these in stock! I also want to keep everything on the board tidy.... I've never been one for funky angling "boutique" components and huge caps bumping into each other..... it's totally unnecessary...... You may "think" these huge components sound better but when you factor in lead inductance etc. they are only adding hash to the sound (which some may like). I ripped those dynamicaps straight out..... perfectly good in a loudspeaker crossover circuit but I see no reason for them dangling about inside the amp apart from "look at me, I'm a dynamicap and I sound good because I cost a lot of money"....... bullshit The EVOX PHE 426 fit perfectly, cost pennies and, IMO, will probably do the intended job a lot better than those massive dynamicaps. Anyways, more than one way to skin a cat and we all do things differently It would be no fun if we all agreed on the same things. I haven't started to REALLY go to town on the board as yet but the first thing I noticed was one of the pads had lifted from the track on one of the diodes...... on closer inspection a few of the pads the power caps were connected to were also a bit iffy..... I have scraped the tracks to expose fresh copper and will be resoldering most of the joints to ensure everything is 100% connected..... I thought MF PCB's were bad, this thing gives new meaning to "bad"!. The ground point situated directly between the 2 x 220nF caps is a fckin' JOKE and I HATE connecting to PCB pins.... I'd much rather hardwire direct to the tracks..... the entire board relies on PCB pins for the connections and these are a "ropey" method of connection, to say the least. Couple in the FACT that ALL of the PCB pin connections are very hard to reach with a soldering iron, I can only assume that, being a British design, they did this to piss people off! I'd rather go IDC connectors than fart about soldering / desoldering these inaccessible stud pins..... the rest of the design is spot on but this aspect of it REALLY pisses me off! Being a "kit amp" you want to be able to remove / fit the board as easily as possible and these pins just make it OH so awkward. Stuart, I'll measure the dimensions of the good quality headphone sockets tomorrow and will send you a couple FOC if they are any good to you.... I reckon they should fit no probs I'll also send you those dynamicaps back as I have no use for them..... the ELNA Silmics / RIFA will be going into the bin so if you'd like them too please let me know. I'll upload pics and comments on the SQ as soon as I have reinstalled the board..... caps and a few resistors to start with and a total "resolder" (paying attention to pad to track integrity) and next up I'll experiment with different flavours of resistor. Mike.
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Post by PinkFloyd on Jan 30, 2010 22:52:34 GMT
I have the board right next to me, as I type....... Some of the resistors could also do with changing ;D R14 / R7 should both be 100 ohm........ R7 is 100 ohm but R14 is 25 ohm ....... No biggie....... all part of the fun
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leo
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Post by leo on Jan 30, 2010 23:31:56 GMT
Nice simple circuit , panny FC or even FM may work nice on the cathodes BTW those 426 Rifa's are nice film caps, you may find those better the expensive audio grade jobs
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Post by Deleted on Jan 30, 2010 23:36:23 GMT
Nice simple circuit , panny FC or even FM may work nice on the cathodes BTW those 426 Rifa's are nice film caps, you may find those better the expensive audio grade jobs Obviously I haven't put any thought into this, because thinking about ancient tech makes my head hurt . Has anybody ever tried Zener diodes in some cathode circuits ?
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leo
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Post by leo on Jan 30, 2010 23:36:32 GMT
Thats surprising regarding the drift in values for FB resistors, you want nice low noise jobbies there, metal film may make it go brighter in that position
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leo
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Post by leo on Jan 30, 2010 23:38:29 GMT
Nice simple circuit , panny FC or even FM may work nice on the cathodes BTW those 426 Rifa's are nice film caps, you may find those better the expensive audio grade jobs Obviously I haven't put any thought into this, because thinking about ancient tech makes my head hurt . Has anybody ever tried Zener diodes in some cathode circuits ? Alex and his love for valves Didn't some folks use batteries on the cathodes?
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Post by guadixman on Jan 30, 2010 23:40:18 GMT
Mike I've hardly used the amp so the caps I fitted have had little use. You'd be quite wrong about ERSE they are cheap but very very good. I've use them in both phono stage and the Bada, I just cannot stand Solens and the Bada was full of them.
Ha the famous WAD track lifting gear - yes tell me about it. Apparently WD PCBS are far better.
I have the same problem with Lehmans original phono stage - a brilliant design, you could'nt make the tracks any shorter but it is even worse than WADs. I've emailed Lehman - I don't even get a negative response. His best design was his first now he's just downright expensive.
The steel case is not a good idea either - have you thought about that at all.
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Post by Deleted on Jan 30, 2010 23:54:09 GMT
Obviously I haven't put any thought into this, because thinking about ancient tech makes my head hurt . Has anybody ever tried Zener diodes in some cathode circuits ? Alex and his love for valves Didn't some folks use batteries on the cathodes? Leo Zener diodes have impedance, the amount of which will vary greatly between 400mA and 1W types. It may be possible in some circuits to kill 2 birds with one stone. i.e. A reference voltage, and a degree of the equivalent of bypassing a resistor with a capacitor. As I said , I haven't put much thought into this,(couldn't be arsed!) so the EE from sunny Queensland may jump all over me ! Alex
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robertkd
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Post by robertkd on Jan 31, 2010 4:36:14 GMT
leoI'm sure you could, is it necessary with this circuit as self bias! Oh and Happy Birthday! Also some maybe interested in this,... www.r-type.org/pdfs/ecl83.pdffrom this site, some interesting stuff www.r-type.org/BTW quoted distortion 0.04% is not too shabby, but I suspect it rises somewhat with higher output but isn't that what you want ;D
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