845s: To biamp or not

I have a new pair of Consonance Cyber 845 monos which I'm very happy with. I have tried them full-range on my Hyperion 938s as well as using a Gallo SA amp to drive the bass modules. I seemed to prefer them full-range, but have been wondering if perhaps I didn't devote enough time to proper level matching and should give the system another go with the Gallo amp.

So.. I'm curious: who would pursue bi-amping in this situation? Does the 845 have sufficient muscle and extension to want to run them full-range on speakers that go to 35Hz, or is bi-amping theoretically preferable at least? Opinions?

The theoretical part of me doesn't like the discontinuity inherent in bi-amping. But perhaps I am all wet.
I have the Cyber 211s and use them full-range on my 93 db efficient Acapella LaCampanellas. The sound is exceptional and the 20 watts that the 211s put out work well.

I have no idea what the efficiency of the Hyperions is, but I would suspect that speakers down to 90 db even in a large room should work full-range with them.

I have never found using two dissimilar amps works.
Im not sure but that amp of yours the 845 is pretty darn good and is a very linear tube. Unless there is a crazy load on the lowend id stay with the 845.
I run Schweikert vr-8 with 96 db. Was running a rogue 120 with great bass(feedback) got the itch to biamp, purchased a krell the rogue kicked its butt. the krell also added too much midbass.Then god knows about precise level matching, there might be a few recodings that sound better bi-ampd...
Hows the 845's with the complexity of classical music?
I may get a second system with high efficiency speakers + 845 dual monos. But I only listen to classical. The 300B tube is too flat in peak fq's. I love sharp dynamics.
Thanks for the replies so far! One of my Cybers blew a cap last night due to using high-voltage tubes (I didn't know!) and so I switched to an 8W Dared 2A3 amp.... I found even THIS little thing could play quite loudly and cleanly and with tight bass through the Hyperions.

Adding the Gallo bass amp to that setup did definitely improve bass dynamics, though.

Bartokfan - I listen to very little orchestral music. I've only had the new gear a week and the first 30 hours or so was all Jazz.. I do listen to some classical and had planned on going through that next. I'll have to wait a bit to get the amp fixed now.

Tbg, the Hyperions are 90dB/W, but are a very easy load (see above). The enjoythemusic review of the Cyber 211s that was so glowing used these speakers.

Paulfolbrecht, I suspect that only you can say what you like.

I had forgotten that the Enjoythemusic review used the Hyperions. If 20 watts with the 211s works with them, your 30 watts should be just fine.

What do you mean that you blew a cap with "high voltage tubes?" I think the driver tubes are the same Phillips 6922 and 5687s I got plus the Chinese 845s. If my experience is any indication, replacing the 845 with a NOS American 845 would do wonders.

They are hard to find and I actually blew an amp with a bad RCA 211; one of three I won on Ebay.

I want to have people tell me what I ought to like and then I'll decide if they were right or not. ;-}

I was using Full Music 845s which apparantly pull too much current. That blew the cap.

I have no plans to venture into NOS 845 territory - too little return for the $. The new Shuguang 845B are supposed to be quite nice for $100/pr.


P.S. Trivial difference but Consonance seems to rate the Cyber 211 at 16W.
Another idea is to stick with one pair of amp(s) for the (main) speakers but make more extended use of the sub I'm already using. Its crossover is now set to 40 which is where the Hyperions are just starting to roll off. I could use a pair of inline 50 or 70Hz highpass filters going into the Cyber 845s and turn up the sub's xover to fill in the gap.

Possible issues:

1) Since my linestage is passive (TVC), my source is then driving these little (FMod) inline xovers, and I don't know what that means to it.

2) The last time I tried this, with a 16W SET amp on Gallo Ref 3s, it just didn't seem to help the amp much... it wasn't able to play much louder (if any) without sounding strained.

Actually I probably just think too much.
Paulfolbrecht, yes Cyber rates them at 16 watts, but mine put out 20, and yes, you are right that this is trivial.

All I can say is that as Enjoythemusic was right when they said the NOS tubes made a great difference, but wrong when they said the GEs were best. The RCAs are far superior.

I am telling you that NOS is superior, now given what you said you must evaluate it for yourself. :<)
I would never argue the point that they're better - but worth $700/pr? Not to me - not now anyway.

Why the hell is it that nobody in the 21st century can make a vacuum tube as good as one 50 years old? It's pretty darn ridiculous.
I was using highly modded Dared 845 amp with my 94 db efficient speakers and it wasnt enough power for me, It is an "integrated amp" so it has volume control. I found that for me the bass never sounded properly, it was too thin all around and though music was enjoyable it missed a lot of instruments altoghether. I like Class A PushPull tube amps, sound more real to me IMHO. With SET 20 watts didnt cut it and 12 watts of push pull class A bring down the house! I turned off my sub....
I had a TVC previously and sold it for the same reasons; something was missing from the music, I can just imagine the same effect adding up...ยท$%&?* (I like SS preamps I guess...still looking for the perfect preamp!)
IMHO SETs are for Horns in a biamped or triamped setup!!

This is what you ought to hear in your system and then you can decide if I was wrong or not!! I like your approach...

Hi Paulfolbrecht

I bought a pair of Hyperion 938 speakers recently. I am considering 845 tube amps to drive it. Looking at several options:
- Hyperion's own HT-845
- Consonance Cyber 845
- Antique Sound Lab 1009 (dual 845)
- exploring others...

How would you describe the sound of the Consonance compared with other 845 amps?
Paul, when I blew one of my Cyber 211s with a bad NOS tube, I approached the U.S. distributor to get a schematic. He said none was available. I sent them to a close friend who modifies gear for repair. Given what you were told by them, I am glad I did not trust them to repair the amp.

I had not thought of trying the 6900 tube and will probably not try it now. I am not sure that having 6900s does not violate your concern whether NOS are worth the cost.

Ethifi, I bought the 211 version of the Consonance Cyber series largely on the strenght of the Enjoythemusic review and a pair being available on Audiogon. I had also heard very favorable things about these amps. I needed greater power than the present 8 watts that I had.

Since getting the amps, I have greatly improved them by using better tubes, carefully isolating the amps on good stands, changing the fuses to IsoCleans, and putting them on ac filtering. I doubt if brand to brand variations are as great as these changes. Also the guy who repaired my amp says he thought they sounded excellent and used very good parts.

How do the prices of the amps you are thinking about compare?
Jsadurni - That Dared ought to be PLENTY of power for 94dB speakers if that is accurate and if they do not have really nasty impedance & phase swings. I had that same amp and it drove 88dB Gallos very well indeed. If it wasn't so huge and ran so hot I would have kept it.

Ethifi - The Consonance amps are 1st rate in every way. Build quality, parts, sonics all top-notch. American stuff like this would cost $10K.

The new Hyperion 845s, however, may turn out to be killer as well.

ASL - you can read all day about them. Good sonics, good deal, for sure, but more than a few have had issues with the gear.

My experience with this 8w Dared amp is steering me well away from bi-amping. If this tiny 8W amp can produce GOOD bass in these speakers, the 845s sure can (I knew that). Well, I mean, I have played with the Gallo amp some more, and while it does tighten up the bass some it is not worth the hassle and extra load on the source. I will try it again with the 845s when I can but when in doubt, go for simplicity, I say.
Paul, I would agree that an American counterpart to the Cybers would cost at least twice as much, but the parts, build quality, and basic circuit show shortcuts to allow the low price. I do like the sonics, however.

The power supply is very simple and limited. It is probably why you had your failure with an output tube that drew more current.

I suspect that there would be only minor variations among 845 amps, with the wiring, output caps, and ac filtering. Better of everything including tubes will improve the sound. The question is what you are willing to add to your basic model.
Tbg, I'm very curious to hear specific shortcuts in parts or "circuit" that you see in the Cybers. The parts are all just about top-tier, if not top-tier. Ditto on the build quality. They are put together very well and the enclosures are faar from simple - the amps could be much cheaper if they were in basic boxes, I am sure.

I may agree with you about the power supply - but, with a Class A design, when you are at 100% power all the time, why build a power supply that can supply substantially more than will ever be drawn? More than the tubes they planned for could ever draw, that is. I certainly agree that it is a least a weak point that they don't allow these higher-current tubes to be used.

Maybe they didn't think of it or want to deal with the issue or maybe it was a conscious decision. Some elements of the amps - like the 5687 drivers which are not common at all, and the designers explanation for their choice - have lead me to believe that a lot of thought did go into these amps.

The fact that they are as quiet as they are also makes me think this isn't simple, basic stuff. It is not easy to make 845 amps as quiet as these are.
Paul, there is no regulation on the power supply and it is just big enough. The caps on the outputs are of unknown origins. I agree that the build quality is okay, but the wiring, inputs and outputs, and circuit are obviously directed at cost cutting.

I am certainly not saying that I don't like them, nor am I saying that I would pay more for them given their quality.

I opted to replace the wiring and to make some reasonable efforts to make them quieter. They will probably become my backup amps or remain in my summer home.

I don't know about the 845s, but my 211s are normal for 10 volt filament amps. Fortunately I have 93 db efficient speakers rather than 103 db efficient speakers where the hum would be objectionable.

I think Enjoy the Music was right about these. They do sound outstanding and can even be as satisfying as the Onganku 211 for far less money.

The main caps on my amps are Rubycon. I'm pretty sure *all* of them were. Maybe they are doing things differently now (mine are brand new) or maybe this is a difference between the 211 and 845 versions, though that seems unlikely.

Again, I thought chokes and oversized power supplies were more appropriate for non class A amps - but I am no expert...

My amps are indeed unusually quiet. The Art Audio Carissa may have been just as quiet but not more so. Talking about speaker hum as well as mechanical tranny hum. Absolutely none of the latter, unlike *many* SET amps...

Anyway we're both happy with them.

What are your "main" amps?
Paul, I saw some Rubycons in mine when I had it open, but I know that the big caps on the output are not Rubycons. It may be that they have changed this in recent amps as mine are from the first batch brought in.

You are quite right about the iron not vibrating. Many of the American made transformers do vibrate quite audibly. As I said, for the price I am very satisfied, but I did decide to not put an additional $750 in them to replace wire, inputs and outputs, and caps.

The amp that I have been using since I ran Beauhorn Virtuosos is the Reimyo PAT777. There is no question in my mind that this SET using WE300Bs is the best sounding amp, but it is very expensive (five times that of the Cybers) and only has 8 watts. Until I got the Cyber 211s, I was seriously thinking about limiting myself to 100 db efficient speakers.The Cybers, however, cause my Acapella LaCampanellas to soar.

I am in love with my H-Cat preamp and soon expect my 100 watt H-Cat amp. I have never heard one, especially the new one, but if it equals the line stage, I am done with both the Reimyo and Cybers.

As I had suspected, your budget is far beyond mine. :-} I think I did very well in the price range with the Cybers. Your system is a level beyond. (Meaning your 10x expendure of cash gets you... 10% further? :-})

Paul, obviously merely buying more expensive equipment does not assure an improvement, but the Reimyo is worth the investment if you can afford it and if you have efficient speakers or a small room.

I have never been comfortable with talking about percentage improvements, and I have not infreqently found less expensive components outperforming more expensive components.

I have been at this hobby for 45 years and well remember when I drove my $2100 new Mercury Capri to pickup my three ARC components (a SP3, Dual 75A, and Dual 51). The store manager noted that these three cost more than my car. I dearly wish I could buy at those prices and earn what I presently do.
I agree that you can't put a "price" on subjective improvements. If $20K speakers do it for you, and you can afford em, then buy em, of course. I didn't mean to suggest it's not "worth it" - it's all relative!

Paul, I just got my Cyber 211 amps back after a bad 211 blew two resistors and a cap. While they were being repaired I had Siltech wire put in from the inputs to the front board and the metal oxide resistor replaced with a metal film resistor.

The improvements are substantial. For one the hum was reduced by 1 mvolt and the transparency was greatly improved largely by a cleaner top end. The wire used within the amps seems to be another instance where the cheapest was used.
Interesting. I find the amps to be - heavenly, as I think I said in another thread today.

I have had a lot of gear through my place in the last year. The combination of the Hyperion 938s with these amps and a transformer linestage is the best it's been - by a wide margin. It is also the most expensive setup - so this is not entirely unexpected.

Anyway, I am sure smitten with the amps. Konchlin had this one nailed. If I meet him I'll have to thank him.

Perhaps someday I'll look into upgrading the amps. I'd want one of the well-known hop-up shops to do it, though, and I don't think the ones I know work on Consonance gear (yet).

Could the Cyber 211 or 845 be placed in a cabinet (20"W x 16"H x 20" D)...open back with perforated steel mesh sides? Or, do they run too hot to allow this?
Hmm. The power tube gets hot but no part of the chassis really does (845 version). If your cabinet is open on the top, I think it'd be Ok.

But why hide them?
Open top cabinet? That'd be a rare beast indeed...

The cabinet is used for space considerations. It sounds like the Cyber 211 may not work in this arrangement.
Tvad, you can see the heat waves arising over the 211. You might think about a whisper fan. I think you would greatly heat whatever was above them.
All right. That answers it. Thanks, guys.