UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Other Discussions > Homebrew Equipment

Notices

Homebrew Equipment A place to show, design and discuss the weird and wonderful electronic creations from the hands of individual members.

Closed Thread
 
Thread Tools
Old 17th Jul 2010, 10:51 pm   #21
neon indicator
Retired Dormant Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Mullard ECL86 3 Watt Economical Amp.

I think they are mostly Class A (Valves used for AM and SSB telephony). Class C only CW and FM
neon indicator is offline  
Old 18th Jul 2010, 10:57 am   #22
GrimJosef
Dekatron
 
Join Date: Sep 2007
Location: Oxfordshire, UK.
Posts: 4,310
Default Re: Mullard ECL86 3 Watt Economical Amp.

Quote:
Originally Posted by neon indicator View Post
There also seems to be a "fashion" to build audio amps with RF PAs in recent years. Seems daft to me.
It's not recent. The datasheet for the 4212-E triode (available here http://www.r-type.org/pdfs/4212e.pdf) gives ratings for both AF and RF operation and the dates on it are 1937 and 1938 !

Whether it's daft or not probably depends on the particular valve and the way it's used and in the end, it will be a matter of opinion. After all, hi-fi's just a hobby and a little "eccentricity" ought to be acceptable

Cheers,

GJ
GrimJosef is offline  
Old 18th Jul 2010, 10:49 pm   #23
G8HQP Dave
Rest in Peace
 
Join Date: Sep 2008
Location: Solihull, West Midlands, UK.
Posts: 4,872
Default Re: Mullard ECL86 3 Watt Economical Amp.

I think the issue is "hi-fi" - which is supposed to mean "high fidelity" i.e the closest approach to the original sound we can achieve given cost, space, power constraints etc. Too much eccentricity puts one instead in the field of "audio" - making a sound which the listener finds pleasant even if it departs significantly from the original sound. Both are valid hobbies, but fans of the latter often think they are pursuing the former and can get upset when the difference is pointed out.
G8HQP Dave is offline  
Old 19th Jul 2010, 12:32 am   #24
GrimJosef
Dekatron
 
Join Date: Sep 2007
Location: Oxfordshire, UK.
Posts: 4,310
Default Re: Mullard ECL86 3 Watt Economical Amp.

Sorry, I do know what the term hi-fi means but I misused it carelessly in my last post. However I'm not really comfortable with restricting the word "audio" to something distinct from hi-fi. I feel audio ought to include hi-fi as well as all the other stuff.

I completely agree though that there is a distinct and, perhaps, eccentric hobby involving kit which sounds pleasant rather than just accurate. I liked your earlier phrase for that kit - "apparatus for enjoying music". It's what this thread's about, since James's ECL86 amp is precisely that. Hence all the earlier comments about what a good "sound" it has, I guess.

It's not what we'd build if we wanted hi-fi - the closest approach to the original - though. Which is why Peter Walker (Mr Closest Approach) abandoned valves for silicon and never looked back. Since the 1950s the pursuit of this has involved improving the speakers, since they are where almost all the distortion comes from. The inevitable consequence of this improvement has been that speakers have become much less efficient. So we have needed much higher amp power to compensate. In the end those eccentrics who want to stick with valves and still chase the highest of hi-fi have either had to start stacking up KT88s in parallel or bite the bullet and switch over to the big AF/RF bottles. The rest of us have chosen to live with lower fidelity levels (me) or convert to silicon (pretty much everybody else I know)

Cheers,

GJ
GrimJosef is offline  
Old 19th Jul 2010, 12:43 am   #25
AlanBeckett
Rest in Peace
 
Join Date: Dec 2008
Location: Burton upon Trent, East Staffordshire, UK.
Posts: 1,686
Default Re: Mullard ECL86 3 Watt Economical Amp.

Well said GJ.
There was an old comment in the '70s that the 'Hi Fi' enthusiast listened to the distortion not the music.
I may be an old codger/pessimist, but I enjoy listening to the local AM stations because that's what they used to sound like.
I fear that there are a lot of people who claim to have listened to 208 who actually didn't.
Alan
AlanBeckett is offline  
Old 19th Jul 2010, 1:46 am   #26
neon indicator
Retired Dormant Member
 
Join Date: Jun 2010
Location: Co. Limerick, Ireland.
Posts: 1,183
Default Re: Mullard ECL86 3 Watt Economical Amp.

Quote:
Originally Posted by GrimJosef View Post
Whether it's daft or not probably depends on the particular valve and the way it's used and in the end, it will be a matter of opinion. After all, hi-fi's just a hobby and a little "eccentricity" ought to be acceptable
Well, I'm selfish. I don't want to pay more for my transmitter valves because someone has made them "fashionable" for a Guitar Amp
neon indicator is offline  
Old 19th Jul 2010, 8:36 am   #27
percival007
Heptode
 
percival007's Avatar
 
Join Date: May 2005
Location: Oxfordshire, UK.
Posts: 852
Default Re: Mullard ECL86 3 Watt Economical Amp.

We seem to be straying slightly off topic here chaps, the Mods will close this thread down!!
I have been following this thread (obviously) but some of the comments have been way over my head!!

The Amp I have built, even though very low power output (only just a Watt due to the supply being lower than specified because of the transformer I am using (because of its availability rather than its technical spec's) to me, reproduces my music collection to a rather high fidelity. (See what I did there!!)

It is my Hobby, building these little Amps (of all description) but more so listening to recorded music. The Amps I build may not be classed, by anyone!!, as ''Hi-Fi'' but I have heard things on records I have not heard on commercially available kit through them.

The main thing is I enjoy listening to them and this latest addition is certainly no exception.

James.
percival007 is offline  
Old 19th Jul 2010, 8:51 am   #28
GrimJosef
Dekatron
 
Join Date: Sep 2007
Location: Oxfordshire, UK.
Posts: 4,310
Default Re: Mullard ECL86 3 Watt Economical Amp.

Getting back to James's ECL86s, in the old days these cost about twice what an EL84 cost. If you go to Watford Valves to buy one now you'll have a choice of one type (nothing special) and they will charge you £28 for it. If you check out EL84s, on the other hand, you'll find 19 different options including some which are still in production. The cheapest is £7.83 - only a quarter of the price of the ECL86. I suspect this is because EL84s are used in guitar amps and ECL86s (AFAIK) are not. In this case, at least, it's the guitarists who are keeping supplies up and prices down, for which I am grateful

Cheers,

GJ
GrimJosef is offline  
Old 19th Jul 2010, 2:07 pm   #29
G8HQP Dave
Rest in Peace
 
Join Date: Sep 2008
Location: Solihull, West Midlands, UK.
Posts: 4,872
Default Re: Mullard ECL86 3 Watt Economical Amp.

Actually, I would class a Mullard design as 'hi-fi', because within the constraints imposed by cost etc. it does try to faithfully reproduce music. Mullard were quite good at specifying performance, so you know where it falls short of perfection. If someone asked them to modify a circuit to introduce "warmth" they would have been rather baffled - their designs aimed to eliminate distortion as far as possible!

Cheap ECL86s can still be found, but you have to be patient and not too bothered about labels. I just bought one for under £4. It is labelled Amperex (i.e. US Philips), the print says made in Holland - but there is no etch code and the innards have the metal tag showing probable manufacture by Tungsram in Hungary.
G8HQP Dave is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 1:10 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.