Hi
Is there differents in sound with the 85A2 valve.
Any thoughts ?
best jan
Location: Denmark
Posts: 98
I'm jan.
Hi
Is there differents in sound with the 85A2 valve.
Any thoughts ?
best jan
It's not in the signal path so I doubt it, unless it's faulty or worn out. Why not ask Glenn for chapter and verse on what it actually does in the power supply circuits he uses it in and what to expect if it goes down?
Last edited by DSJR; 21-10-2012 at 10:51.
Tear down these walls; Cut the ties that held me
Crying out at the top of my voice; Tell me now if you can hear me
Hi Jan,
The 85A2/CV449 voltage regulator valve is part of the power supply electronics inside Croft preamps, and therefore does influence the sound, as indeed my experiments in that area have shown.
I've recently been playing with quite a few different ones, from Phillips, Amperex, Valvo, and various types of Mullards, and it's the latter that have impressed me the most, sonically, giving a level of detail retrieval, overall naturalness, solidity and superb projection with vocals, making the others sound anaemic and 'processed' in comparison.
With the Mullards, in general, the older the vintage the better - I've had superb results from late 60s production ones, such as this, which even came with a guarantee/certificate of authenticity:
That's probably the best sounding one I've found so far. However, I also took delivery of one of these yesterday, bought from a valve seller on eBay I've used before: http://www.ebay.co.uk/itm/3706195892...84.m1439.l2649
...and it sounds very good indeed. He's got a few more available, if you fancy buying any yourself. I'm also waiting on these 1968 Chelmer-branded Mullards, in their original boxes, to arrive from the States, and have high hopes for these:
Marco.
Main System
Turntable: Heavily-modified Technics SL-1210MK5G [Mike New bearing/ETP platter/Paul Hynes SR7 PSU & reg mods]. Funk Firm APM Achromat/Nagaoka GL-601 Crystal Record Weight/Isonoe feet & boots/Ortofon RS-212D/Denon DL-103GL in Denon PCL-300 headshell with Funk Firm Houdini/Kondo SL-115 pure-silver cartridge leads.
Paul Hynes MC head amp/SR5 PSU. Also modded Lentek head amp/Denon AU-310 SUT.
Other Cartridges: Nippon Columbia (NOS 1987) Denon DL-103. USA-made Shure SC35C with NOS stylus. Goldring G820 with NOS stylus. Shure M55E with NOS stylus.
CD Player: Audiocom-modified Sony X-777ES/DAS-R1 DAC.
Tape Deck: Tandberg TCD 310, fully restored and recalibrated as new, by RDE, plus upgraded with heads from the TCD-420a. Also with matching TM4 Norway microphones.
Preamps: Heavily-modified Croft Charisma-X. LDR Stereo Coffee. Power Amps: Tube Distinctions Copper Amp fitted with Tungsol KT-150s. Quad 306.
Cables & Sundries: Mark Grant HDX1 interconnects and digital coaxial cable, plus Mark Grant 6mm UP-LCOFC Van Damme speaker cable. MCRU 'Ultimate' mains leads. Lehmann clone headphone amp with vintage Koss PRO-4AAA headphones.
Tube Distinctions digital noise filter. VPI HW16.5 record cleaning machine.
Speakers: Tannoy 15MGs in Lockwood cabinets with modified crossovers. 1967 Celestion Ditton 15.
Protect your HUMAN RIGHTS and REFUSE ANY *MANDATORY* VACCINE FOR COVID-19!
Also **SAY NO** to unjust 'vaccine passports' or certificates, which are totally incompatible with a FREE society!!!
See my previous post, Dave. It's not in the audio signal path, but it's part of the power supply (in the rectification stage, I think), and many listening tests have confirmed that it *does* indeed influence the sonics of Croft preamps
As an aside, the best ECC83 (also featured in Croft preamps) I've heard, by a country mile, are these NOS 1961 Mullard M8214s:
Utterly, utterly STUNNING sound! Available from here: http://www.tubemonger.com/Mullard_CV...fe_p/2050m.htm
Marco.
Main System
Turntable: Heavily-modified Technics SL-1210MK5G [Mike New bearing/ETP platter/Paul Hynes SR7 PSU & reg mods]. Funk Firm APM Achromat/Nagaoka GL-601 Crystal Record Weight/Isonoe feet & boots/Ortofon RS-212D/Denon DL-103GL in Denon PCL-300 headshell with Funk Firm Houdini/Kondo SL-115 pure-silver cartridge leads.
Paul Hynes MC head amp/SR5 PSU. Also modded Lentek head amp/Denon AU-310 SUT.
Other Cartridges: Nippon Columbia (NOS 1987) Denon DL-103. USA-made Shure SC35C with NOS stylus. Goldring G820 with NOS stylus. Shure M55E with NOS stylus.
CD Player: Audiocom-modified Sony X-777ES/DAS-R1 DAC.
Tape Deck: Tandberg TCD 310, fully restored and recalibrated as new, by RDE, plus upgraded with heads from the TCD-420a. Also with matching TM4 Norway microphones.
Preamps: Heavily-modified Croft Charisma-X. LDR Stereo Coffee. Power Amps: Tube Distinctions Copper Amp fitted with Tungsol KT-150s. Quad 306.
Cables & Sundries: Mark Grant HDX1 interconnects and digital coaxial cable, plus Mark Grant 6mm UP-LCOFC Van Damme speaker cable. MCRU 'Ultimate' mains leads. Lehmann clone headphone amp with vintage Koss PRO-4AAA headphones.
Tube Distinctions digital noise filter. VPI HW16.5 record cleaning machine.
Speakers: Tannoy 15MGs in Lockwood cabinets with modified crossovers. 1967 Celestion Ditton 15.
Protect your HUMAN RIGHTS and REFUSE ANY *MANDATORY* VACCINE FOR COVID-19!
Also **SAY NO** to unjust 'vaccine passports' or certificates, which are totally incompatible with a FREE society!!!
At that price, they bloody well should be
The 85A2 in my Croft is over twenty years old and the only valve not to have been replaced now. For £7 on the eBay link there's no issue at all and I'm always happy to have my hunches proved wrong
Tear down these walls; Cut the ties that held me
Crying out at the top of my voice; Tell me now if you can hear me
Give one a go, Dave. Trust me, I think you'll like the improvement (just allow about 48 hours for the valve to fully burn-in). You know that the Marco-boy is rarely wrong!
Marco.
Main System
Turntable: Heavily-modified Technics SL-1210MK5G [Mike New bearing/ETP platter/Paul Hynes SR7 PSU & reg mods]. Funk Firm APM Achromat/Nagaoka GL-601 Crystal Record Weight/Isonoe feet & boots/Ortofon RS-212D/Denon DL-103GL in Denon PCL-300 headshell with Funk Firm Houdini/Kondo SL-115 pure-silver cartridge leads.
Paul Hynes MC head amp/SR5 PSU. Also modded Lentek head amp/Denon AU-310 SUT.
Other Cartridges: Nippon Columbia (NOS 1987) Denon DL-103. USA-made Shure SC35C with NOS stylus. Goldring G820 with NOS stylus. Shure M55E with NOS stylus.
CD Player: Audiocom-modified Sony X-777ES/DAS-R1 DAC.
Tape Deck: Tandberg TCD 310, fully restored and recalibrated as new, by RDE, plus upgraded with heads from the TCD-420a. Also with matching TM4 Norway microphones.
Preamps: Heavily-modified Croft Charisma-X. LDR Stereo Coffee. Power Amps: Tube Distinctions Copper Amp fitted with Tungsol KT-150s. Quad 306.
Cables & Sundries: Mark Grant HDX1 interconnects and digital coaxial cable, plus Mark Grant 6mm UP-LCOFC Van Damme speaker cable. MCRU 'Ultimate' mains leads. Lehmann clone headphone amp with vintage Koss PRO-4AAA headphones.
Tube Distinctions digital noise filter. VPI HW16.5 record cleaning machine.
Speakers: Tannoy 15MGs in Lockwood cabinets with modified crossovers. 1967 Celestion Ditton 15.
Protect your HUMAN RIGHTS and REFUSE ANY *MANDATORY* VACCINE FOR COVID-19!
Also **SAY NO** to unjust 'vaccine passports' or certificates, which are totally incompatible with a FREE society!!!
Your wish is my command sir!
Tear down these walls; Cut the ties that held me
Crying out at the top of my voice; Tell me now if you can hear me
Lol - it could give you a nice little upgrade for not a lot of dosh! Btw, what's in your amp, 85A2-wise, at the moment?
That would be useful to know, including a piccy, if you can manage it
Marco.
Main System
Turntable: Heavily-modified Technics SL-1210MK5G [Mike New bearing/ETP platter/Paul Hynes SR7 PSU & reg mods]. Funk Firm APM Achromat/Nagaoka GL-601 Crystal Record Weight/Isonoe feet & boots/Ortofon RS-212D/Denon DL-103GL in Denon PCL-300 headshell with Funk Firm Houdini/Kondo SL-115 pure-silver cartridge leads.
Paul Hynes MC head amp/SR5 PSU. Also modded Lentek head amp/Denon AU-310 SUT.
Other Cartridges: Nippon Columbia (NOS 1987) Denon DL-103. USA-made Shure SC35C with NOS stylus. Goldring G820 with NOS stylus. Shure M55E with NOS stylus.
CD Player: Audiocom-modified Sony X-777ES/DAS-R1 DAC.
Tape Deck: Tandberg TCD 310, fully restored and recalibrated as new, by RDE, plus upgraded with heads from the TCD-420a. Also with matching TM4 Norway microphones.
Preamps: Heavily-modified Croft Charisma-X. LDR Stereo Coffee. Power Amps: Tube Distinctions Copper Amp fitted with Tungsol KT-150s. Quad 306.
Cables & Sundries: Mark Grant HDX1 interconnects and digital coaxial cable, plus Mark Grant 6mm UP-LCOFC Van Damme speaker cable. MCRU 'Ultimate' mains leads. Lehmann clone headphone amp with vintage Koss PRO-4AAA headphones.
Tube Distinctions digital noise filter. VPI HW16.5 record cleaning machine.
Speakers: Tannoy 15MGs in Lockwood cabinets with modified crossovers. 1967 Celestion Ditton 15.
Protect your HUMAN RIGHTS and REFUSE ANY *MANDATORY* VACCINE FOR COVID-19!
Also **SAY NO** to unjust 'vaccine passports' or certificates, which are totally incompatible with a FREE society!!!
Ordered and paid for...
Can't "whip it out" at the moment, since it's on and glowing nicely at present
Tear down these walls; Cut the ties that held me
Crying out at the top of my voice; Tell me now if you can hear me
Lol - well, we can't disturb that, can we? When your bulb is less 'angry', try it then.
Nice one... Let me know what you think when the new valve arrives
Marco.
Main System
Turntable: Heavily-modified Technics SL-1210MK5G [Mike New bearing/ETP platter/Paul Hynes SR7 PSU & reg mods]. Funk Firm APM Achromat/Nagaoka GL-601 Crystal Record Weight/Isonoe feet & boots/Ortofon RS-212D/Denon DL-103GL in Denon PCL-300 headshell with Funk Firm Houdini/Kondo SL-115 pure-silver cartridge leads.
Paul Hynes MC head amp/SR5 PSU. Also modded Lentek head amp/Denon AU-310 SUT.
Other Cartridges: Nippon Columbia (NOS 1987) Denon DL-103. USA-made Shure SC35C with NOS stylus. Goldring G820 with NOS stylus. Shure M55E with NOS stylus.
CD Player: Audiocom-modified Sony X-777ES/DAS-R1 DAC.
Tape Deck: Tandberg TCD 310, fully restored and recalibrated as new, by RDE, plus upgraded with heads from the TCD-420a. Also with matching TM4 Norway microphones.
Preamps: Heavily-modified Croft Charisma-X. LDR Stereo Coffee. Power Amps: Tube Distinctions Copper Amp fitted with Tungsol KT-150s. Quad 306.
Cables & Sundries: Mark Grant HDX1 interconnects and digital coaxial cable, plus Mark Grant 6mm UP-LCOFC Van Damme speaker cable. MCRU 'Ultimate' mains leads. Lehmann clone headphone amp with vintage Koss PRO-4AAA headphones.
Tube Distinctions digital noise filter. VPI HW16.5 record cleaning machine.
Speakers: Tannoy 15MGs in Lockwood cabinets with modified crossovers. 1967 Celestion Ditton 15.
Protect your HUMAN RIGHTS and REFUSE ANY *MANDATORY* VACCINE FOR COVID-19!
Also **SAY NO** to unjust 'vaccine passports' or certificates, which are totally incompatible with a FREE society!!!