Cyber 845 monoblocs

[dpastern]

Hi guys,

I'm in the process of doing a deal to secure a pair of these beauties, anyone own or have owned a pair of these?  I'll be partnering them up with a pair of SF electa amators (89db, 6ohm load from memory).  I don't listen to huge volumes, typically 90-95db tops.  I listen to a wide variety of music, but seem to be gravitating more towards acoustic stuff as I get older.

Dave

[rollo]

 I own the Cyber 211s. Same amp but less power. The 845 version with the Chinese tubes is bright sounding. You will need to buy aftermarket tubes. Grant Fidelity carries the TJ meshplates for $425 which I use. I have NOS GE, RCA, Valve art [ stay away], Shungang [ stay away] and the TJ Meshplates. The 6DJ8 should be a Mullard and the driver tube a Tungsol 5687. The JJ and Phillips that come with the amp are OK but not the best choice. Also check to see if the amp actually has Mundorf caps If Auri caps are at the coulping positions [ only two per amp] change them out. A V-cap copper at the input[ 6DJ8] and an Audio Note copper at the driver tube[ 5687] will blow your mind. Have it tested first. Just in case.


charles

[dpastern]

Thanks for the reply Charles.  I believe the 845 tube is a better sounding tube (than the 211), although the 211's midrange is slightly better by all accounts.  845 NOS tubes are exceedingly rare, and ultra expensive, I cannot justify the expenditure to be honest.  That leaves current range stock.  I've heard a few reports of people using the TJ valves damaging the monoblocs (current is too high apparently), so would be staying away from them.  I'm only going on what others have personally advised me via other audio forums.  I've heard very good things about the Shuguang 845B units - solid price and decent sounding.  Sure, not as good as NOS RCA (which I believe are better than NOS GE units by all accounts). 

I've noted the 6DJ8 and 5687 suggestions and will try them.  I'm not electronically inclined, so I'd probably be as useless as the proverbial re: Mundorf caps.  The units I'm being are only 5 months old and have been lovingly looked after by the one and only owner.  He seems a decent chap and I see no dodginess in the units.  He's only selling the units because I started talking to him asking for advice about the Cyber 845 units and I mentioned the new 845S variants (with tube rectifiers vs SS ones in the original 845 unit) and he must have these new units for a variety of reasons.  It wasn't an intentional sale by him, more luck on my part than anything.  These units sell for AU $4400 new in Australia (near half price of anywhere else in the world), and I'm getting it for a very decent price I must say, probably near 25% of what you'd pay new in the US or Europe.  I'm not usually very lucky, but I seem to have been in the right spot and right time for once. 

As to mods, I probably will get them done, but I have no intention of invalidating the warranty (which I believe is 5 years).  After that is a different story - I've heard via some other forums about mods to these units making huge improvements over what is generally very good already.  Bonus.

Thanks again for the reply.

Dave

[mgalusha]

I've owned both the Cyber 845's and the 211's. Both can sound really nice. The 845's will just squeak out 24W into 8 ohms and the 211's will manage 16W. For an 89dB speaker that little bit of extra power will help. I traded my 845's to a friend who had the 211's as he needed the little bit of extra grunt for his speakers. At the time he had 91dB sensitive Meadowlark's and now has the Audiokenesis Jazz Modules, which are 92dB I think. It drives them very well indeed.

$20 says your unit will have caps marked Auricap, at least both of these amps did. I did find it interesting that in both cases the caps I pulled out didn't look like any Auricap's I'd ever seen and I've seen quite a few over the years. Perhaps they are produced in China under license, don't know but they don't have the same physical construction as the US made ones.

The 845C's are also an option instead of the 845B, I preferred them but be aware they will only dissipate about 70% of the power that a 'B will, so the bias needs to be adjusted accordingly. The difference is a metal plate in the C vs graphite in the B.

Also the 7119/ECC182 are an option in place of the 5687. I prefer the Philips ECC182 over the Tungsol 5687. Not a huge difference but I found them a little more transparent.

mike

[dpastern]

Well, I got the amps yesterday, haven't powered them up yet (need to get my speaker cables fixed to ensure no loose connector/cable issues that could stuff up the output transformer by driving the amps without a speaker load).  I have no real understanding on checking the electronics etc, and won't do so whilst the units are still within warranty.  Once the units are out of warranty, I will make changes to the caps/resistors/cabling etc.  I expect a few grand worth of modifications will make these very good amps even better!

Dave

[rollo]

  Actually about a grand[ V-caps] $700 without. We replaced every resistor and power cap. Diodes, rectifier and wiring as well. An Audio Note silver RCA and new IEC. The results were amazing. Truly a world class sound.
  Now there is one serious issue to be concerned with. If the 845 tube goes south the output trannie can fry. There is no protective circuit. I would bias the tubes 20% lower than recommended. Also check to see if you have a 5A fuse in lieu of the 8A for the Chinese edition. Good luck and enjoy.


charles

[daviddsailor]

The warranty for my 845S monoblocks, which are Australian delivery, was 12 months. I have had them for almost 2 years. The only problem I have had is the valve rectifiers flashing internally when first switched on. My mains voltage is often 251VAC. I finally got a set of rectifiers that don't flash (yet). I swapped the 5687's for TungSols and noted a small improvement in hi frequency clarity. I replaced the Auricaps with Jensen copper PIO and the improvement overall was worth every cent they cost me. Now I have replaced the RCA connectors with CMC pure copper silver plated and changed the shielded wire from the RCA to the first valve with silver plated RF co-ax. Huge improvement in clarity and detail. Sounded a bit bright and tizzy for the first few days but settled down to a beautiful clear and extended sound.

[dpastern]

That's interesting David - because Greg advised me that the warranty for the older and original Cyber 845 is 2 years. 

Where are you located?  I'm in Brisbane.  Can you PM me more specific details on the upgrades that were performed?  Did you do them yourself, or have someone do them for you?

Do you think that these improvements would also benefit the older Cyber 845 units in the same manner as with your newer 845S units?

I'm not in a financial position at this point of time to have any mods done on my units, but what sort of rough cost would it be to get this done by a competent tech?

Cheers,

Dave

[daviddsailor]

If Greg told you they are warrented for two years I'm sure he knows what he is talking about. My Users Manual for the 845S types states 1 year. I'm in Melbourne. I did the mods myself because I have been in electronics for over 50 years and the mods are quite straight forward. New chums should be very carefull working on mains powered equipment. It must be turned off with the mains plug disconnected and as these amps operate on about 1000V DC, make sure they have been off for 5 minutes or so before poking inside, and check with a multimeter just to be on the safe side. I assume the mods would benefit the older 845 amps. These latest 845S types are supposed to be an improvement over the earlier types but I don't think sticking a meter on the front and tarting up the external appearance could be classed as much of an improvement so I assume they have done other things. Anyway, the mods I have done are a considerable improvement IMHO and I note elsewhere on another forum that someone else has done similar mods and still has a few tricks up his sleeve. The Jensen caps cost less than $150.00AUD posted from the US, the copper/silver RCA's $28.00 locally and the coax I had. The mods took me about 2 hours total and any competent tech (or DIY buddy) could do the job. Best regards, David.

[dpastern]

Thanks David.  I don't know anyone (or trust) anyone in Brisbane to do the job.  Not many modern electronics techs have experience with valves and OPT imho.   Do you know anyone in Brisbane that you'd trust to do the job? 

I am surprised that such simple parts replacements make such a big difference.  I quite like the sound of my monoblocs, although there are issues with impedance matching with the Sonus Fabers and ultimately, I do not feel that the combination is a good match, and that I am achieving the best SQ from my system. 

Dave

[daviddsailor]

I'm not trying to say that you should mod the 845S amps, they are great amps. I suppose that after you have tried everything else you gravitate to modifying. After reading opinions on the net and soaking everything up I realised that a lot of people swear by capacitor upgrades and for me that is relatively easy but equipment is only part of the battle. Room acoustics have a huge effect on sound quality. Even after I purchased a very expensive source and speakers there were huge improvement to be had with room acoustics. My wife never ceases to tell our friends how she came home from a weekend away to find two single bed mattresses propped up behind each speaker. This simple exercise led me on a path of understanding as to what room reflections can do to smear music images, reduce depth and generally muck up the listening experience. Naturally I removed the mattresses quick smart and started experimenting with acoustic panels and diffusers. There is a good argument for trying this path before upgrading or modding equipment and it's often much cheaper! I might be able to recommend someone to mod the amps but it would take a lot of chasing around. Suggest you approach a store that sells valve amps and find out who does their repairs. Valve amps are not a black art and there would be lots of people capable of doing mods, you just have to hunt them down. Regards.

[rollo]

   However I am saying you really should consider the cap mod.
   The V-Caps we installed took 30 minutes. Right there in front of you when the botom cover plate is removed.
   Since the V-caps have been changed to Dueland Alexandras. The biggest improvement yet. Not really expensive and the improvement wrought is priceless. Really !
  Lenehan Audio is a dealer in Aus. I'm sure Mike can set you up. If you could swing the Dueland VSF go for it.
   The values are .1uf and .47uf. One pair each.


charles

[daviddsailor]

I have recently fitted a pair of Psvane Hi-Fi Series 845 tubes. These are the lesser versions (and cheaper) of the Psvane Collection Series 845 tube. Straight out of the box they were a considerable improvement over my 845B tubes that had done about 2000hrs. Bass is tighter, dynamics are better and the top end is clearer. The soundstage is better and there is more depth. I'm told (by the supplier) that the more expensive Psvane Collection Series 845 are even better. Naturally they are a lot more expensive but I think I will wait to hear that they are better from others. Of course, if I was a cynic I could say that any new tube would be better than one that had done 2000hrs but in this case I can't remember the stock Shuguang 845B's ever sounding as good as the Psvane tubes.