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Wakefield Turntables
04-08-2016, 14:56
Now that I'm well on my way to becoming a DECCA geek I got round to thinking if it might be a good idea to get a phonostage specifically built for DECCA RIAA or purchase one with the option already built in. So far I've seen the latest audio research reference pre-amp costing mucho dosh and the latest phonostage from ifi audio. Any other suggestions?

Jimbo
04-08-2016, 15:42
Croft preamps seem to be optimally set up to work with the Decca cartridge. Cant say the RIAA is bang on but funnily enough they sound very good indeed.

I wonder why?:)

Arkless Electronics
04-08-2016, 16:00
I don't know if it may be of any interest to you but I can build phono stages specifically for Decca (or any other) EQ and, in many cases, I could modify the EQ in an extant phono stage to be to Decca rather than RIAA standard.

EDIT: Just a thought (I can't be bothered to revise the detailed history), IIRC the Decca eq would refer only to the correct replay of old records which were actually recorded to Decca standard rather than to RIAA standard and would have no bearing on the replay of standard records, even if using a Decca cartridge.
It would only really be of use to someone wanting to get the exact correct response when replaying rare (?) archive records made between lets say 1947 and 1953 (a wild guess!) and then only if manufactured by Decca or a company licensing their techniques...

I'm probably stating the obvious and teaching me granny to suck eggs there... and may even be less than 100% correct... but just saying:)

If you're well aware of that and it is indeed what you wish to do then, as I said at the top, I can help

walpurgis
04-08-2016, 16:34
EDIT: Just a thought (I can't be bothered to revise the detailed history), IIRC the Decca eq would refer only to the correct replay of old records which were actually recorded to Decca standard rather than to RIAA standard and would have no bearing on the replay of standard records, even if using a Decca cartridge.
It would only really be of use to someone wanting to get the exact correct response when replaying rare (?) archive records made between lets say 1947 and 1953 (a wild guess!) and then only if manufactured by Decca or a company licensing their techniques...

I'm fairly sure that's right Jez and that RIAA has long been standard across the board. I'm not aware of any other replay equalisation in common use.

Wakefield Turntables
04-08-2016, 16:41
Hmmm I need to do my homework and come back to this one.:)

Arkless Electronics
04-08-2016, 17:10
Columbia, New Orthophonic, Victor, Old RIAA, Decca FFSS and FFRR all available! Thorns whittled to Shibata profile while you wait! (I may get serious enquiries from DL103 owners...:D) A huge untapped market awaits :lol:

I'll get my coat....

walpurgis
04-08-2016, 17:36
(I may get serious enquiries from DL103 owners...:D)

Do serious owners have DL-103's? :D

(Marco will probably send the Denon brigade after me now :eek:)

Arkless Electronics
04-08-2016, 17:47
Do serious owners have DL-103's? :D

(Marco will probably send the Denon brigade after me now :eek:)

:D I thought I would have had a bite by now :D

Barry
04-08-2016, 18:44
Do serious owners have DL-103's? :D

(Marco will probably send the Denon brigade after me now :eek:)

Yep - I still use mine, as well as one of several EMTs

Barry
04-08-2016, 18:46
Columbia, New Orthophonic, Victor, Old RIAA, Decca FFSS and FFRR all available! Thorns whittled to Shibata profile while you wait! (I may get serious enquiries from DL103 owners...:D) A huge untapped market awaits :lol:

I'll get my coat....

What about the BBC equalisation curve? Can you do that as well?

daytona600
04-08-2016, 18:57
DECCA geek Andrew do you mean Decca cartridges or Decca FFRR curves

RIAA - used phonostages with all the Decca & all major RIAA curves & more like a subtle tone control
& they might be a myth anyway

http://www.analogplanet.com/content/deccalondon-records-myth-exploded#0vv74TSkJZqKATl9.97

Cartridges
used them for decades & work with most phono stages , but excel with great ones

Fully passive RIAA & DECCA equalisation
• Unique continously variable input impedance loading,
matches every cartridge (adjustment even while playing)

http://www.project-audio.com/main.php?prod=phonoboxrs

Barry
04-08-2016, 19:06
Andy, sounds like you are confusing record playback equalisation with input impedance of the phono input (that is the electrical loading of the cartridge).

Deccas are quite happy with the now long standard input impedance of 47kOhm (in fact Decca quote 50kOhm). However there are some who find that an increased loading of 33kOhm is preferable. To some extent it depends on the system; in mine 47k is fine, in my friend's we found 33k to be better. We experimented with even higher loading (reducing the input impedance in stages down to 24kOhm). There was no improvement, only increasingly impared tracking due, I assume, to the increased electrodynamic loading and hence damping of the cartridge.

To make matters worse there are some enthusiasts (notably in the US) who suggest the loading should be reduced by running the cartridge into loads as high as 1MOhm. I haven't tried this as I find 47k is fine, and see no reason to increase the impedance (which practically is not so easy to do).

There is also no real need to fiddle about with capacitance values. Changes in this area seem to have less of an effect with Deccas than they do with other fixed-coil cartridges.

As other have commented, Glenn Croft is a Decca user, so his preamps will presumably be set up to allow the Decca cartridge to operate in an optimum electrical environment.

Arkless Electronics
04-08-2016, 19:18
What about the BBC equalisation curve? Can you do that as well?

Why of course:) and NAB

Barry
04-08-2016, 19:22
http://midimagic.sgc-hosting.com/mixcurve.htm

Although the RIAA curve was proposed in 1954, it was not universally adopted and it took several years before the various record companies all complied.

However unless you have some recordings which were made before 1964, I wouldn't worry.

Arkless Electronics
04-08-2016, 19:28
Abit more QI stuff on it... IIRC Decca FFRR EQ was first used by Decca (78RPM) in response to a war dept need for extra high fidelity reproduction of something or other to fool the Nazi's.... or I could have dreamt that :scratch:

struth
04-08-2016, 19:41
Think they used wire recordings during the war for their imaginary armies etc. Miles of it.

daytona600
04-08-2016, 22:11
Abit more QI stuff on it... IIRC Decca FFRR EQ was first used by Decca (78RPM) in response to a war dept need for extra high fidelity reproduction of something or other to fool the Nazi's.... or I could have dreamt that :scratch:

No dream Jez
The original Decca company was started in the 19th century, but it's first involvement with music was with a portable record player used in the trenches during the 1914-18 world war. In the 1939-45 war the government asked Decca to produce a system to identify British submarines from German ones, which resulted in the ffrr (full frequency range recording) system. In 1944 Decca produced the first ffrr music discs. The first LP record (mono) came in 1951 followed by stereo in 1958. Engineers Bayliff and Cowie then designed the Decca ffss (full frequency stereo sound) tonearm and playback head which had Mk I, II and ill versions

topoxforddoc
05-08-2016, 11:26
Now that I'm well on my way to becoming a DECCA geek I got round to thinking if it might be a good idea to get a phonostage specifically built for DECCA RIAA or purchase one with the option already built in. So far I've seen the latest audio research reference pre-amp costing mucho dosh and the latest phonostage from ifi audio. Any other suggestions?

Andrew,

I asked Graham Tricker to build me a TRON Seven Reference to suit my Decca FFSS MkIV C4E. It sounds stunning. However, that's mucho dosho! I listened to his new baby TRON Convergence phono about 18 months ago, and it had 90% of the SQ for £900 (MM), as opposed to nearly £5k. I'm sure that he could build you a Convergence to suit the Decca. If you were closer, I would suggest you come and have a listen.

Charlie

Arkless Electronics
05-08-2016, 12:39
There is nothing special or unusual about Decca cartridges that requires a non standard phono stage... one cannot build a phono stage "to suit" Deccas;)

My remarks in my first post were to do with Decca eq to suit records made by Decca at one time, not to suit the cartridge.

YNWaN
05-08-2016, 12:59
Yeah, I think the Decca (as in the record label) recording curve is being confused with the Decca cartridge.


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