Amity Horror becomes Amity V2 becomes …
- andrew Ivimey
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#1 Amity Horror becomes Amity V2 becomes …
You know, I am getting sick of this amplifier; wish I’d never started etc etc. Anyway, AmityV1 was a horror. It surprised me that although it worked and I suppose didn’t sound so bad, there was much wrong with it.
AmityV2 moved into the science fiction realm. I have been playing with it for five days now. First I rebuilt the amplifier so components and stuff were sensibly, if more traditionally, laid out. It helped. At its best, up to the weekend, it has sounded poor through to extraordinary but the frustrating thing is that now I know what Lynn Olson means when he says most pre-amps are grey sounding with an Amity, that Amity has no sound of its own but (hint) Lynn and his chum Gary went on to build Aurora (oh yeah, why ) and Mr Olsen also designed a rather good, if special pre-amp just with Amity in mind, I should have known that I’d be in for a very long ride… yeah right, there is always Karna.
So, if you are vaguely familiar with the circuit what can possibly go wrong? I’m happy with simple CCS (resistor, cap,resistor) on the 6N6P anodes. Who has used 6N6Ps before? Does anyone like them? I should swap in a pair of ECC99s but I’ve run out of steam. 6N6Ps are okay for now. (7044, 5687 etc etc - another thread)
There are only three caps a channel; two are ultrapath and one, between earth of interstage and HT positive of output, is all there is to go wrong. I tried Solens, then Obliggatto film in oil on the 2A3s and finally got stuck at some metal foil, polypropylene caps from Taiwan; cheap. The first ultrapath is 6.8mfd Mundorf supreme. The make of cap really makes a difference. All three types of cap altered sonically for a few hours until they got used to what else was hapening.
So, poor sounds = shrill and nasty.
Extraordinary sounds = massive dynamics and slam but nearly
always overall grey coloured even though the resolving power of the
amplifier was amazing (reliably hearing bits in the mix I’d never
heard before, being pulled into the music etc etc)
But that kind of extraordinary sound was frustrating – what could be wrong? Low impedance input (as per text) helps hugely (Wadpre2 supposedly has 600ohm output. This works and isn't bad) TVC is lovely providing there is welly to drive into it. So, a Convergent Amplifier Technology preamp (big voltage swing, I'm guessing has low impedance output as it looks like a cathode follower) and TVC was one nice way to go. Just using WADpre2 was easier.
But I am going to need a preamp where I really didn’t want one. Now I’ve got enormous slam and volume, detail and musicality and have resorted, for now, to my Elac with ribbons (88dB sensitive) speakers instead of Fostexbackloaded 208s that I have been using since Monday.
(One set of old Shuguang 2A3s is worn out, though, and this set me back a while until swapping them for a pair of TJs and Phroarrr! Back on track. The old Shuguangs really distort badly. They were a matched pair once)
Having given up on the idea of ever having a neat and tidy build, and as there were a couple of holes in the chassis from the large Obliggattos that were now relatively small Taiwan caps, I decided to put in a 76 line stage, giving me a choice of input without another box.
This is not an Amity any longer though.
That is what is playing now. Welly, dynamics and …well I’m knackered and aching, eyes and ears about to give up. The bath calls. But for now I am pleased. Every day the amp sounds different, - strange -
(A quad of TJ mesh sound marvellous by the way. These are for 'best' when all else is done.)
AmityV2 moved into the science fiction realm. I have been playing with it for five days now. First I rebuilt the amplifier so components and stuff were sensibly, if more traditionally, laid out. It helped. At its best, up to the weekend, it has sounded poor through to extraordinary but the frustrating thing is that now I know what Lynn Olson means when he says most pre-amps are grey sounding with an Amity, that Amity has no sound of its own but (hint) Lynn and his chum Gary went on to build Aurora (oh yeah, why ) and Mr Olsen also designed a rather good, if special pre-amp just with Amity in mind, I should have known that I’d be in for a very long ride… yeah right, there is always Karna.
So, if you are vaguely familiar with the circuit what can possibly go wrong? I’m happy with simple CCS (resistor, cap,resistor) on the 6N6P anodes. Who has used 6N6Ps before? Does anyone like them? I should swap in a pair of ECC99s but I’ve run out of steam. 6N6Ps are okay for now. (7044, 5687 etc etc - another thread)
There are only three caps a channel; two are ultrapath and one, between earth of interstage and HT positive of output, is all there is to go wrong. I tried Solens, then Obliggatto film in oil on the 2A3s and finally got stuck at some metal foil, polypropylene caps from Taiwan; cheap. The first ultrapath is 6.8mfd Mundorf supreme. The make of cap really makes a difference. All three types of cap altered sonically for a few hours until they got used to what else was hapening.
So, poor sounds = shrill and nasty.
Extraordinary sounds = massive dynamics and slam but nearly
always overall grey coloured even though the resolving power of the
amplifier was amazing (reliably hearing bits in the mix I’d never
heard before, being pulled into the music etc etc)
But that kind of extraordinary sound was frustrating – what could be wrong? Low impedance input (as per text) helps hugely (Wadpre2 supposedly has 600ohm output. This works and isn't bad) TVC is lovely providing there is welly to drive into it. So, a Convergent Amplifier Technology preamp (big voltage swing, I'm guessing has low impedance output as it looks like a cathode follower) and TVC was one nice way to go. Just using WADpre2 was easier.
But I am going to need a preamp where I really didn’t want one. Now I’ve got enormous slam and volume, detail and musicality and have resorted, for now, to my Elac with ribbons (88dB sensitive) speakers instead of Fostexbackloaded 208s that I have been using since Monday.
(One set of old Shuguang 2A3s is worn out, though, and this set me back a while until swapping them for a pair of TJs and Phroarrr! Back on track. The old Shuguangs really distort badly. They were a matched pair once)
Having given up on the idea of ever having a neat and tidy build, and as there were a couple of holes in the chassis from the large Obliggattos that were now relatively small Taiwan caps, I decided to put in a 76 line stage, giving me a choice of input without another box.
This is not an Amity any longer though.
That is what is playing now. Welly, dynamics and …well I’m knackered and aching, eyes and ears about to give up. The bath calls. But for now I am pleased. Every day the amp sounds different, - strange -
(A quad of TJ mesh sound marvellous by the way. These are for 'best' when all else is done.)
#2
Yep, I used them to drive 300b's last year, Dave "Dove" used them a couple of years ago, and found there were good and bad ones, I can't remember what the difference was, but I know the ones I have are the bad sort.Who has used 6N6Ps before? Does anyone like them?
Maybe someone else can point to the "good" ones.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
- Cressy Snr
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#3
Hey Andrew, that's not fair!
You've got ten valves on your push pull amp. I've only got nine !
Seriously well done Sir! These amps are a lot better when you put a bit of yourself into them. Even though the Amity is supposed to be a "proven" design, I wouldn't worry about it not being an Amity anymore. Isn't that what DIY is all about?
Steve.
You've got ten valves on your push pull amp. I've only got nine !
Seriously well done Sir! These amps are a lot better when you put a bit of yourself into them. Even though the Amity is supposed to be a "proven" design, I wouldn't worry about it not being an Amity anymore. Isn't that what DIY is all about?
Steve.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
#4
Hi Andrew and Nick,
The bad ones are the ones from Novosibirisk, the good ones are Reflektor.
From Dave.....
cheers,
-- Andrew
The bad ones are the ones from Novosibirisk, the good ones are Reflektor.
From Dave.....
To be honest, I thought the Novosibirisk ones sounded reasonable, but I don't have any of the others to compare.there is another guy regularly advertising them as NOS 1960s stock
the way to spot them is the lying down triangle with 6H6pi inside
a roman numeral below left and a two figure number below right
the two figue number is the year of manufacture...65 i have seen on ebay recently
mine are 67 and are light years ahead of the others
which all have a pentagon on them but varying script
and are produced at the novosibirsk factory
cheers,
-- Andrew
- andrew Ivimey
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#6
Um, I've got both types and actually I can't really hear any difference. Maybe I should listen harder!
more anon . - I will re-route the heaters for ECC99 but I can't remember where I put them.
more anon . - I will re-route the heaters for ECC99 but I can't remember where I put them.
- pre65
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#7
Hi-i've done some "remote dowsing" and they are in the back room lower floor (where we listened to your amps)andrew Ivimey wrote:- I will re-route the heaters for ECC99 but I can't remember where I put them.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- andrew Ivimey
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#8
Good guess - there is a basket full of various valves but the ecc99s are in boxes...somewhere.
Anyone ever heard Orchestral Zeppelin? I'm not recommending it - just asking.
Anyone ever heard Orchestral Zeppelin? I'm not recommending it - just asking.
- pre65
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#9
In a drawer in the kitchen !andrew Ivimey wrote:Good guess - there is a basket full of various valves but the ecc99s are in boxes...somewhere.
.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
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#10
The ones I'm using in the phono have the pentagon too. Alexer1 has a couple of lots of the lying down triangle ones on ebay at the moment...mine are 67 and are light years ahead of the others
which all have a pentagon on them but varying script
and are produced at the novosibirsk factory
- pre65
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#12
I bloody hope so !Greg wrote:Phil, you'll make for someone a lovely wife
I am experimenting with "pendulum dowsing" at the moment so it will be interesting to see where Andrew finds them.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- andrew Ivimey
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#13
upstairs, back bedroom in a box surrounded by ecl82s.
I don't think dowsing is the answer, Philip.
I don't think dowsing is the answer, Philip.
- Dave the bass
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#14
At Philips age he has to dose a lot... Oh... my mistake .... you're talking about dowsing
DTB
DTB
"The fat bourgeois and his doppelganger"
- andrew Ivimey
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#15
pair of ECC99s fitted - better.
This amplifier is very 'fast'.
Drums can actually sound 'real'!
This amplifier is very 'fast'.
Drums can actually sound 'real'!