Squared to Cubed

95Dyna · « **Reply #20 on:** 28 Jun 2016, 03:38 pm »

Quote from: bjski on 15 Jun 2016, 04:14 am

Hmmm,do I sell my 7's and get 4 cubed or do I buy 28/2?

I'm interested in the 7B SST2 > 4B3 question. Bought the 7's in '09 to drive a very difficult load but have since bought new speakers with a much easier to drive profile at 8 ohms nominal, 3.6 ohms minimum and 91 db efficiency rating. Has me wondering if swapping out the 7B2's for 4b3 will provide the new input circuit improvements that have been documented without the loss of power presenting an issue. Any thoughts out there would be appreciated.

NekoAudio · « **Reply #21 on:** 29 Jun 2016, 05:19 am »

Quote from: 95Dyna on 28 Jun 2016, 03:38 pm

I'm interested in the 7B SST2 > 4B3 question. Bought the 7's in '09 to drive a very difficult load but have since bought new speakers with a much easier to drive profile at 8 ohms nominal, 3.6 ohms minimum and 91 db efficiency rating. Has me wondering if swapping out the 7B2's for 4b3 will provide the new input circuit improvements that have been documented without the loss of power presenting an issue. Any thoughts out there would be appreciated.

You'll probably have to share your desired SPL in order to answer this question.

Anonamemouse · « **Reply #22 on:** 29 Jun 2016, 06:10 am »

Quote from: Hikmer on 26 Jun 2016, 11:03 pm

Isn't this thread about Bryston Cube amps???

No, it is about excellent music. The amps (both squared and cubed) are just a means to reproduce this excellent music in the best possible way!

Quote from: 95Dyna on 28 Jun 2016, 03:38 pm

I'm interested in the 7B SST2 > 4B3 question. Bought the 7's in '09 to drive a very difficult load but have since bought new speakers with a much easier to drive profile at 8 ohms nominal, 3.6 ohms minimum and 91 db efficiency rating. Has me wondering if swapping out the 7B2's for 4b3 will provide the new input circuit improvements that have been documented without the loss of power presenting an issue. Any thoughts out there would be appreciated.

From experience I'd say that chances of improved soundq uality are roughly 100%. The question is more if the amount of improvement is worth the money. The only way to know for sure is testing... Locate a dealer that allows you to take one home for a couple days.

CanadianMaestro · « **Reply #23 on:** 29 Jun 2016, 12:14 pm »

Quote from: 95Dyna on 28 Jun 2016, 03:38 pm

I'm interested in the 7B SST2 > 4B3 question. Bought the 7's in '09 to drive a very difficult load but have since bought new speakers with a much easier to drive profile at 8 ohms nominal, 3.6 ohms minimum and 91 db efficiency rating. Has me wondering if swapping out the 7B2's for 4b3 will provide the new input circuit improvements that have been documented without the loss of power presenting an issue. Any thoughts out there would be appreciated.

Agree with A-mouse above -- audition if possible, in your own setup.

How did you measure the "3.6 ohms minimum" of your speakers? Or is that the mfr's spec? I expect that value is dependent on the dynamic range of the recordings you listen to mostly, and the loudness you listen at. Still, I prefer monoblocks so my vote would be to keep the 7B2's. And use the dough to upgrade other links of your audio chain -- sources maybe or room treatments.

srb · « **Reply #24 on:** 29 Jun 2016, 12:51 pm »

Quote from: NekoAudio on 29 Jun 2016, 05:19 am

You'll probably have to share your desired SPL in order to answer this question.

Or we can roughly calculate maximum SPL with the 4B³ given your new speaker specs and assuming a 10ft listening distance with speakers away from the walls ..... 109dB - 111dB (if in fact the speakers can physically and/or thermally produce that SPL).

So it sure seems like the 4B³ would have enough power.

You can list the pros and cons for the switch .....

Pros
- new input circuitry designed for improved sound
- lower idle power consumption (70W vs 430W)
- space saving (and one less power cord)
- x years longer warranty

Cons
- no longer separate mono amps that can be located closer to speaker
- slightly less Class A watts for lower level listening
- ~ $5K used value now, would be ~ straight swap for new 4B³ which would immediately have ~ $4K used value

Tough call. While some have expressed preference in keeping more powerful mono amps, I admit I've more recently been in the downsizing / efficiency / minimalist mode (if you can call a 300W/500W per channel Class AB amplifier "minimalist"!).

Steve

Rod_S · « **Reply #25 on:** 29 Jun 2016, 01:39 pm »

There's certainly something to be said for the big reduction in idle power. I looked up the 7B3's specs and those have gone down considerably as well, 80 watts so a pair of those would only be 160 vs 430 of the SST2's. The 28's however didn't change much at all.

I think in reality though most would be hard pressed to actually hear any differences between same model SST2's vs cubes in a blind AB or ABX test. There would have to be a serious flaw in one or the other for one to stand out in my opinion. If the comparison was between tube vs solid state or even total Class A vs Class AB I could see more people hearing differences. I can even see differences being heard between the 7B-SST2's vs 4B3 at low volume levels due to the 7's probably being in Class A vs the 4B3 would have gone into Class AB.

CanadianMaestro · « **Reply #26 on:** 29 Jun 2016, 03:40 pm »

Quote from: Rod_S on 29 Jun 2016, 01:39 pm

There's certainly something to be said for the big reduction in idle power. I looked up the 7B3's specs and those have gone down considerably as well, 80 watts so a pair of those would only be 160 vs 430 of the SST2's. The 28's however didn't change much at all.

The 14B2 is about 110W idle or so? With 2 x 7B's inside it, that's pretty good economics. Still, I switch it off when not used. Wonder why the 28's weren't changed.

Rod_S · « **Reply #27 on:** 29 Jun 2016, 04:03 pm »

I'm sure James can answer. In fact the numbers on the 28's actually went up, rather than stay the same or go down.

Rod_S · « **Reply #28 on:** 29 Jun 2016, 04:05 pm »

According to the manual the 14SST2 is 215 at idle while the 14B3 is 170.

CanadianMaestro · « **Reply #29 on:** 29 Jun 2016, 07:27 pm »

That's quite a bit idle. Glad I don't subscribe to the 'phile voodoo about leaving it on all of the time ...

NekoAudio · « **Reply #30 on:** 29 Jun 2016, 08:59 pm »

Quote from: srb on 29 Jun 2016, 12:51 pm

Or we can roughly calculate maximum SPL with the 4B³ given your new speaker specs and assuming a 10ft listening distance with speakers away from the walls ..... 109dB - 111dB (if in fact the speakers can physically and/or thermally produce that SPL).

So it sure seems like the 4B³ would have enough power.

::shrug:: The 4B3 is just enough for my speakers and my specific use case. Based on 95Dyna's speaker description, I think my speakers are easier to drive. If I was using 95Dyna's speakers in my setup, I might consider a pair of 7B3 or a 14B3 over a single 4B3. Personally I like to keep peak demand within an amplifier's rated specs.

95Dyna · « **Reply #31 on:** 5 Jul 2016, 09:45 pm »

Thanks for all the feedback on my 7B SST2 > 4B3 question and apologies for being missing in action since posing it 6/28 (long story and off topic). My thoughts, addressed in one post above, were 7B SST2 to 4B3 would be a minimal cost option so if the 4B3's provide an enhanced sound profile in my new lower power requirement scenario why not consider it. Harry Fisher's new review of the 4B3 at Inner Ear seems to indicate that the 4B3 does provide a noticeable improvement over the 7B SST2's he has been using for the past few years.

BTW, CanadianMaestro, the speakers are the new Focal Sopra 2's and the minimum load spec is the manufacturer's. My room will be 16 x 27 x 8. I listen to anything from quiet acoustic, small jazz ensembles all the way up to Led Zeppelin, the Allman Brothers and thunderous Mahler Symphonies. It's the latter of these that give me pause when considering this but once again my old speakers dipped to .8 ohms at 30 hz then again at 340 accompanied by some nasty phase angles. The Sopras are a walk in the park by contrast

CanadianMaestro · « **Reply #32 on:** 5 Jul 2016, 11:46 pm »

@95Dyna

Looks like you may be very happy with a 4B3/Sopra combo.

(I am with my 14B2/Mozarts!)

Let us know how it works out for you.

Pete

Rod_S · « **Reply #33 on:** 6 Jul 2016, 12:29 am »

I just read the review. Glowing as always for a Bryston product from Inner Ear. No surprise there, it's like they are an extension of the Bryston marketing department

No mention of objective testing though which seems to be the defacto review methodology these days so it's not a criticism specifically of Inner Ear but of the review business in general. I did read one review that James posted that had measurements and surprisingly what was reported on there wasn't as much a difference as I might have expected. This was the Hi-Fi News review. This only showed some of the measurements and they indicate all the measurements will be posted later so perhaps these will show more differences that aren't as they describe, fractional.

LarryRS · « **Reply #34 on:** 6 Jul 2016, 12:55 am »

Anyway, to get back to the original thread - is there any news on the possible update of the 4BSST squared to cubed?

LarryRS

James Tanner · « **Reply #35 on:** 6 Jul 2016, 12:59 am »

Hi Larry

No sorry it is not looking like it will be feasible. The safety and certification people are telling me we would have to submit amplifiers for approvals if we make any changes to the innards.

james

James Tanner · « **Reply #36 on:** 6 Jul 2016, 01:01 am »

Hi Folks - Here's another 4B review from Germany which you can translate through Google.

HI James

One great 4B³ review is online on one of the most popular online HiFi high end platforms in German speaking markets..:

http://www.hifistatement.net/

Best regards

Edvard
AViTech, Dkfm. Edvard Potisk e. U.
Czerningasse 16
1020 Vienna, Austria

Grit · « **Reply #37 on:** 6 Jul 2016, 05:54 am »

Quote from: James Tanner on 6 Jul 2016, 12:59 am

Hi Larry

No sorry it is not looking like it will be feasible. The safety and certification people are telling me we would have to submit amplifiers for approvals if we make any changes to the innards.

james

That's disappointing. Thanks for trying though James. Doesn't diminish my love for my SST2 amps. Just gonna have to wait for the 4b4 and 6b4 one day.

Rod_S · « **Reply #38 on:** 6 Jul 2016, 10:22 am »

Quote from: Grit on 6 Jul 2016, 05:54 am

That's disappointing. Thanks for trying though James.

I echo this. Thanks for trying for all those that were interested in upgrading.

CanadianMaestro · « **Reply #39 on:** 6 Jul 2016, 02:46 pm »

Quote from: Rod_S on 6 Jul 2016, 12:29 am

I just read the review. Glowing as always for a Bryston product from Inner Ear. No surprise there, it's like they are an extension of the Bryston marketing department No mention of objective testing though which seems to be the defacto review methodology these days so it's not a criticism specifically of Inner Ear but of the review business in general.

I'm with you on this. I stopped reading reviews and rely on auditions at home/in-store. It's fatiguing to read all the praise without "cons" mentioned. And as you know, measurements don't reflect actual real-room performance. Hook, line, sinker.

From what I've read, the cubed amps likely make after-market cabling pointless (unless one really wants to "color" the sound), especially into the power amp from line pre? With my squared, I found audible improvements with after-market bal cabling vs. cheap stock cabling. Power cabling too.