i still have a few of these too!Quote:
Originally Posted by Jack Williams
Anthony,TD...
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i still have a few of these too!Quote:
Originally Posted by Jack Williams
Anthony,TD...
I guess the other site couldn't handle my Wizard robe!
Lately cooking up a revolutionary "new" amp circuit, with all the advantages of single ended and also those of push-pull, without the disads. Not a new idea, but in the past "unavoidably compromised". Methinks I have solved the problem. Winding the transformers at present for a type 45s version. "Watch This Space"!
If is's as good as I think, the 4x6550 version will appear.
Here is a typical interstage transformer that that capacitor replaced. I still think one can get a better sound through a capacitor than a transformer, in spite of the current fashion for using them.
It seems one can get disks (sic) of what appears to be 90% bass drum. One can also buy "stereos" where they have carefully designed the large speakers to resonate big around 100hz. This means they don't need to supply a very big amp.
This causes the so-called "Jukebox" one note bass; although I think a bit of an insult to Jukeboxes.
So neigbours at the rear decided to open up the Summer with a front yard party. A tent attached to the front of the partially built-in carport to enhance the projection of the speakers, and proceed to boom at huge decibels (my widow glass was rattling.) for twelve hours starting in the middle of the afternoon yesterday (Saturday our time).
What can little ole me do about it with a lot of half-drunk maoris there? Arthur, the head of the house is actually a nice guy. But how nice really subjecting me and other neigbours to that lot? People on the other side of the road two sections away were aware of it.
There was no possibility of out-booming them, as Ecofan speakers are carefully designed not to boom.
But I can out-tweet them...
In the junk room was a little "TOA" brand outdoor PA horn speaker. Rated at 5WRMS (8Wmax) it said 100db @ 1 metre. So I mounted it just below my high up (on the outside) bathroom window where I could perfectly angle it to cover the outdoor party area. With the little 10W amp (2xEL84) I use in the workshop to check tuners, preamps etc and an oscillator I found that 1WRMS at 3000HZ made a really big noise.
When I tried it out about mid-day when they started up again I tried it at a not big volume and later a burst of one watt.
Arthur and wife were visiting in a flash, and I said to them the boom box was a bit much, and one thing followed the other, or words to that effect. I am always on the front foot in these sort of situations, and it has been a nice lower level most of the today, and better if they play something civilized like Reggae.
P.S. I'll have to invite soon Arthur to have a few "burbs" and hear a pair of proper speakers. And I have plenty of Reggae and dub. Some sort of "deal" could perhaps get him a pair of Ecofan speakers and they'd hear a good 25 and 40 hertz for a change, and we would all be much happier! I guess...
Here is a photo of an amp.
That booming was pretty traumatising. My friend Sue next door, who's house is right in line with their boomers was quite distraught, and was very appreciative of my managing to mitigate it somewhat for their following day/night blast.
I could invite Arthur over sometime to sit under the trees and listen to my little outdoor JBLs around the other side of the house. He could hear the lovely bass-lines of some of the same bods he plays. Who knows what the Summer will reveal...
If I play something believable like guitar or a piano trio and go for a walk along the road, from the other side of the nearby intersection (in line really through the trees) it does sound like a live performance. Which you hear from the street around here, as in this street there are a few schools with halls for hire, and the bands hire them for band practice. During the weekends. They always sound good.
P.S. "Is that a string quartet I hear playing in the bushes?"
The above amp was in a feature in a local architecture magazine (Urbus). I have no idea how he got it up there, as it's about as much as I can lift!
and he/she uses Technics turntables as well.....nice :) Ecofan and Technics :rave:
Regards D S D L
But what are those speakers? Looks like something from a nightclub (to match the Techies! ;)) but possibly Tannoys? (Don't think so, but not sure, maybe it is a PA rig) :scratch:
Pass :scratch: over to you Jack ?
Regards D S D L
They are in fact Tannoys, but I have no idea of the model. For the photo they removed the cables!
Here's a photo I took today just to bug the younger generation.
They look like I15's with the grilles removed.
http://img2.buy.si/2/20154073.jpg
That's great, thanks for clarifying.
hi jack thats a lovely skirt you have there you remind me of the monks in the mountain monastrys in italy ,i will have to send you over some bottles of whiskey for christmas.
there were 2 hifi shows in ireland in last 2 weeks one in n.ireland in belfast and mr cloney had one in dublin i was at both .i was speaking to a uk valve amp maker called pure sound and was telling him about your new amp circuit -he said about using transistors in a similalar way i wrote it down his description but cant find now. he had his linestage which had a 300b in it and 845 mono blocks on demonstration -he said that he prefered 845 to the 211
I'm told they're CTA 15s. Does that ring a bell?
Jack.
Just to read about such audio delicacy is amazing; to live it and breathe it must be intoxicating. As a musician I struggle with kit that can barely translate the complexities of the sound I envision, especially as I've been playing at/with electronica more and more and pop stuff less and less. I could only imagine the thunderous reproduction of my sonic mayhem with such beautifully simple, unfettered equipment. My speakers are a lash-up at best- never mind the awesome combos you guys are running. From a true lover of all things musical, I applaud the spirit of this undertaking and only wish the best upon those involved with these awesome animals. Rock on in the very best way, all of you, to your own best end, whatever that seems to be in the midst of the discovery of how well your gear is being received...
The tremendous Mediaeval Baebes have got their new double album "Temptation" at the manufacturer at last, available for Christmas. Their two existing DVDs, "Live at Gloucester Cathedral" and Tenth anniversary one are absolutely supurb and continue to be my highest "rotation" DVDs. Only available from their site these days. www.mediaevalbaebes.com
Well, the push-push circuit does in fact work a treat. I did find though that I do need a bigger power supply and more HT for four of type 45 in this circuit than for two of 6A3 in single ended. I really need some 100 extra volts to get the best out of it but as is I do get about 4wrms/ch to listen to. Even that though, sounds quite grunty compared to a single-ended 45. But the sound is quite beautiful, in fact when I first got a channel of it going on Saturday, and then tried the local classical music station on the rubbish bench speaker that's what came immediately to mind: how beautiful it sounded.
On the livingroom speakers last night the bass was quite impressive on DVD. (other than radio, of course the first thing I tried was the Mediaeval Baebes!) That drum was realistic, and it did a great job on the voices. I quite impressed myself!
It ran out of headroom on a heavy "dub" CD in that if you pushed it up too much it intermodulated, but the depth of bottom was there. I made the OPTs for about 18wrms. The bigger power transformer will also improve the bottom, regardless of the extra power.
More voltage will ice the cake, but I'll also have to keep an eye on the plate dissipation. If I can come up with 10wrms I'll be happy.
After a couple of nights of extended listening, can't say there is much wrong with the amp as it is. It seems to have enough volume for most things. The bottom end is extended and meaty with good damping. In use at present the amp does not have the power measured on the bench, as I only had one channel set up at first. The power supply sagged somewhat supplying two. A beefed up power transformer will give room for more voltage and taps, but I don't think I can go much more toward AB1. About two-thirds class A right now. The 45s plate dissipation is about seven watts at present, but the current is as high as you'd want to go, although the voltage across the 45s is only 150v. I will develop this direct coupled design for SV-811-10s. Monoblocks. I think they'll be pretty nice.
I thought "Push-push" sounded a bit rude. It differentiated from "Push-pull" though. Balanced single-ended is closer to what's happening anyway.
So "What's Happening"?
Got the bigger power transformer created and installed yesterday. On the tap that got me the original bench results but with both channels going, the amp sounded amazingly more powerful. (It was measuring 3WRMS with smaller transformer both channels going; 4WRMS with bigger transformer) but after some listening I thought the 45s felt a bit hot, so I backed it off to just one notch (20 volts HT notches) above where the smaller transformer was. I'm not sure, feeling the 45s whether they are a lot cooler, but the transformer is noticeably so, so the current must be quite reduced.
But personally, I think the amp sounds better on the reduced voltage/power...
It is surprising how powerful this setup sounds for the low power. On about 94db speakers.
Okay, I have borrowed a friend's 6A3 amp as above for comparison with this new amp. The new one sounds every bit as powerful, perhaps more so I think. Swapping quickly many times between the two amps while pausing on a range of music DVDs I find I do always much prefer the new amp. While there is nothing in it as to the top end, this amp sounds fuller and clearer. Without the 2nd harmonics I would guess. The bottom end sounds bigger and more extended. I think it has a warmer and fatter sound, perhaps more "friendly". More three-dimensional?
I'll try to get a perfected one over for a review in the coming year.
This is the BSEA! It stands beside the SEOTL.
Quote:
Originally Posted by Jack Williams
That would be very interesting :)
Regards D S D L
i have 2 friends going to auckland in the new year and i have given them 6 bottles of the local n.ireland bushmils whiskey for you to keep all the engineering going.
it was below zero here and i had to put a heating bulb in the roof space .i will have to try to get a set of your single ended otl power amps for next year.
it will be nice to hear your new amp when you finish proto typing keep well murray
More compareings of the amps. I thought they were a bit "apples and oranges" in that the 45 is a polite friendly bottle anyway, compared with the more up-front 6A3.
So the other night I just tried plugging in a set of 2A3s. They're about midway between 45s and 6A3s in sound.
The amp came alive! The intermodulation basically disappeared, probably because of the extra headroom. I thrashed on into the night...
In the morning I checked it out on the bench. Really only a small tweak on a couple of settings optimized the best power/waveform/balanced clipping syndrome. You are hogtied in direct coupled as to the class the output is running in. The 2A3s are cruising with only 45ma plate current and 150 volts across, where the 45s are pushed at 40ma and 150 v. That's with the full 400v HT, but the 45s are backed off to a lot less. However the 2A3s don't mind the full volts, so I get a good five watts.
WOT! No more than one bottle in the amp above?
Ah yes, BUT! Firstly the bottles are cruising compared to the one in the6A3 amp. But you also get a choice between two quite different sounding amps of similar power. Adam thought the 6A3 was "etherial" and the BSEA sounded "HiFi". Whatever that is..
A happy Christmas and a merry New Year to all!
Francis:Quote:
Originally Posted by Giant Haystacks
Three bottles each will be duty-free.
Murray.
PS: They'll help me get my Steam-powered turntable up and running.(Don't laugh!)
A check of the junk room came up with these bits. The platter from Collaro's version of the Garrard 301 and Garrard bearing. Very heavy, being die-cast metal. A good reason to play with model stream. Never had something to drive, before another guy in a hobby mag made one. His however is a pretty bad sound. I have a good low mass arm to go with this one.
greetings from the sunny southern seas,
here is a link to picture and video of aucklander simon jansens' handsome, (but aurally iffy), steam powered turntable - the inspiration for 'jack williams' current efforts mentioned above.
http://trialbysteam.com/2010/12/05/s...record-player/
quite lovely to look at...
adam
hi,
for your mild amusement,
a
:lol:
Regards D S D L
Nothing much to say to that.
While not a huge priority, this is progressing, with belt groove being made, and lip removed. Also, the parallel hole in the Collaro platter tapered for the Garrard bearing. This diecast platter is much heavier than the Garrard 310 one. I have a heavy lead intermediate fly-wheel for between belt from engine and belt to platter. Should be very smooth, and could be driven from any sort of motor.
I have my eye on lovely British spirit boiler and Aussie donkey engine kit. Should be great looking and rival some of the best turntables for performance. A bit of a hoot.
Sounds amazing - look forward to some pics!
THE problem that has me thinking, is that on all the engines the pulley is vertical, whereas one needs a horizontal one for a turntable.
Might be worth looking out for a steam engine kit that has a governor. You will get much better speed control then.
Yes, too right! I have thought of that, and have the bits to do just the job on whatever engine I come up with. Same as the one on a wind-up gramophone, but on a smaller scale.
The friends did get here, and we had a really enjoyable afternoon with music DVD they knew, but mostly talking. We took each others photos, although I wish I'd washed my hair! Here is photo I took.
They were impressed with the balanced single ended sound and he's keen to get the 100W version. Off the top of my head I probably quoted a vastly under price. But heck, they'll be in Saudi Arabia!
Lost track of the photo there, but with luck, here it is. Friends from Ireland. Didn't think about the whiskey at the time come to think of it!
Murray that guy could be my Dad's brother :eek: He looks very like my Dad.
Regards D S D L
The BSEA amp has evolved somewhat.
Changing the driver from 6N7 to 6SN7 has improved the rise time and lowered the noise.
This version is the direct coupled amp using two of type 6A3 valves per channel.
I have the 6A3 courtesy of Francis,driving AER MD2's in an active two way Oris horn config using a Trinnov ST2 for room optimisation and its digital 2way crossover feature.
The 15" bass is driven by a MC2 MC450 at the moment but Francis is sending over his other 6A3 so I can have a play with a fully active setup using the 6A3's :)
Got my BD Design Ref 2010 bass cabs almost finished,some pics on the wam in the DIY forum looking forward to getting it all together
First I knew he had two 6a3's unless the other one is Noel Clonney's of Clonney HiFi.Quote:
Originally Posted by RobsterD
Lovely amplifiers but they do need to be built into a bigger case. They run very hot, so give them plenty of ventilation.
Regards D S D L
A bloke we know is a dairy farmer. He has a classic valve system consisting of Revox G-36 valve tape recorder, Quad II preamp and monoblocks (not sure of the speakers in use) playing to the cows in the cowshed at milking. He says the cows notice the difference; due to the milk production.
It could be that the cows have grown up with the old valve radios in the shed, and the solid state was a bit of a shock.
hi,
i'll find out what the cows are listening to - something bucolic i expect...
rob - glad to hear you've got 'giant haystacks' amp in your system - looking forward to your impressions
cheers all,
a
I don't believe a word of it - a load of old bull.
;)
Quit milking it, AlexQuote:
Originally Posted by Alex_UK
of course it's all about the moo-sic...
Maybe an Ecofansound setup would make New Zealand's dairy production even more prolific!
hi,
i've scanned and posted an article murray has written for the nz vintage radio society newsletter, too big to fit here, have a look at:
https://picasaweb.google.com/arustyr...ral4A70Project
cheers,
adam
A sunny-ish, rather windy winter Sunday here, not hugely cold, but enough to layer up a bit.
Looks like my Auntie Rose (who was Uncle Roy on weekdays).Quote:
Originally Posted by Jack Williams