[clive101]

I have PMC MB2 SE speakers with 7b3 amps and considering an upgrade to 28b3 power amps.
I do not push my current amps as they never get warm what would I expect to gain from the larger amps if I were to upgrade..?

[john1970]

Why are you considering the upgrade?  How big is your room and how loud do you listen to music?

According to PMC website your speakers are 90 dB 1W 1m efficient with 8 ohm (nominal) impedance and I doubt you will benefit from the extra watts / current that the 28B3 delivers.  If you were driving very inefficient speakers (80-85 dB 1W and 1m) at low impedances (2-4 ohms) the 28B3 would be a worthwhile consideration.  With your speakers I doubt you would gain much. 

Other AC members have mentioned that the 7B3 is about 95% of that of the 28B3.  Others please feel free to chime in...

[clive101]

Thank you for the information, my dealer recently compared the two amps with a client, and in general talking recommend an upgrade as the difference in power really did make a difference.
I just wondered if any one had compared the two for general advice.
 
Edit
My room is 25 x 15 feet, low to medium volume, around very loud talking is the max average volume I would use

[john1970]

Thank you for the information, my dealer recently compared the two amps with a client, and in general talking recommend an upgrade as the difference in power really did make a difference.
I just wondered if any one had compared the two for general advice.
 
Edit
My room is 25 x 15 feet, low to medium volume, around very loud talking is the max average volume I would use

Was the client using the same speakers you have?  I would arrange with the dealer to have an in-home demo for a week so you can listen to the 28B3 and compare it carefully to the 7B3.

[jimangie1973]

I'm very skeptical of the advice your getting from your dealer.  The 7B3 monos themselves have massive power and overkill already based on what you've indicated with speakers, room size, and listening levels.  I think you'd be perfectly happy with the sound of a 3B3.

On the other hand, if you've got the cash and really want some beautiful amps to gush over, the purchase makes sense.

[clive101]

The client was using different speakers and surprised the dealer how different the amps were, hence commented that with the PMC mb2 se would respond if not the same but even better.

Forgive me, I am relatively new in HiFi and the 7b3, I thought were plenty enough to drive the Mb2Se but question what I would gain with the 28b3 ..?

I did not want to go down the route of a demo for say a few weeks if the gain was not worth the effort and expense.

So seeking advice.
 

[CanadianMaestro]

Frankly, with a sens. of 90-dB and your stated listening level and room size, your 7B3's are plenty.

If you think that you're not hearing your music the way that you would like (with excellent recs), then you should consider changing other elements of your system, upstream from the 7s.

[what would you gain with a 28B3? imho....a lighter bank account.  ]
cheers

[gbaby]

Frankly, with a sens. of 90-dB and your stated listening level and room size, your 7B3's are plenty.

If you think that you're not hearing your music the way that you would like (with excellent recs), then you should consider changing other elements of your system, upstream from the 7s.

[what would you gain with a 28B3? imho....a lighter bank account.  ]
cheers

Agreed.

[clive101]

Thank you for the information looks like we all agree, it seems my bank account may not be lighter after all .

[clive101]

If you think that you're not hearing your music the way that you would like (with excellent recs), then you should consider changing other elements of your system, upstream from the 7s.

Thank you for you help, I have been upgrading upstream of the amps but that's a long story. I am playing digital files and learnt very quickly that noise and RF were an issue for me, finally, have it under control. 

[Aschen]

Just a related curiosity, but I'm not sure how many people can really use the power of the 28s? It would seem to me that the 7Bs could let release the magic smoke from well over 99.9% of home speakers even at the high end.

I have relatively large and in efficient/sensitivity dynaudio C4s ~87dB I think, and I recently ordered a 4B3 thinking the extra head room of the 7Bs wouldn't be needed. Im not sure what I would do with 28Bs except admire them or find some 18" sealed subs to drive. Captain Obvious: 1000 WPC is alot particularly when its a conservative rating!   

[CanadianMaestro]

I have relatively large and in efficient/sensitivity dynaudio C4s ~87dB I think, and I recently ordered a 4B3 thinking the extra head room of the 7Bs wouldn't be needed. Im not sure what I would do with 28Bs except admire them or find some 18" sealed subs to drive. Captain Obvious: 1000 WPC is alot particularly when its a conservative rating!   

Good point.

My speakers are 90-dB, 6-ohms nominal, and I went from a B100-SST alone, then to a 4B2 (3 yrs), and finally to a 14B2. Very happy. Won't be upgrading anything, in the future. Will take full advantage of the 20-yr warranty!! 

[clive101]

Yes the 7b3 have all the power I need, if I play for example Trentemoller Chameleon and crank up the volume, the windows and whole house gets effected and I am not joking you feel the bass through your body, an experience trust me one blast is enough.

The dealer explains it's more how the amps control the speakers and not the extra power if that's makes sense....?

[gbaby]

Yes the 7b3 have all the power I need, if I play for example Trentemoller Chameleon and crank up the volume, the windows and whole house gets effected and I am not joking you feel the bass through your body, an experience trust me one blast is enough.

The dealer explains it's more how the amps control the speakers and not the extra power if that's makes sense....?

You could have gotten by with just the 2.5 cubed. But, at least you are covered for the future. 

[Elizabeth]

The biggest plus might (might?) be tighter bass slam.
Bigger amps usually have more control over speaker excursion.
And depending if the op speakers are 4 ohm or 8 ohm nominal impedance ..If 4 ohm the speakers might sound more dynamic. particularly high impact moments.
If 8 ohm I don't know if any difference would be noticed.
Also with lower efficiency speakers the difference would be more apparent. Higher efficiency speakers I think less noticeable.

Detail and such should remain the same.

(one other point that it may be your dealer just wants some 7B3 as 'used' trade in equipment?)

[CanadianMaestro]

Dealers sell gear. That's their mission in L-I-F-E. More $$$ inflow, the better (for them).
period.

[john1970]

The client was using different speakers and surprised the dealer how different the amps were, hence commented that with the PMC mb2 se would respond if not the same but even better.

Forgive me, I am relatively new in HiFi and the 7b3, I thought were plenty enough to drive the Mb2Se but question what I would gain with the 28b3 ..?

I did not want to go down the route of a demo for say a few weeks if the gain was not worth the effort and expense.

So seeking advice.
 

Along the line with what others have said, I doubt you would hear a difference.  My advice is save the money or put it towards something else (a nice vacation, buy some more music, etc.).

[TJ-Sully]

I have PMC MB2 SE speakers with 7b3 amps and considering an upgrade to 28b3 power amps.
I do not push my current amps as they never get warm what would I expect to gain from the larger amps if I were to upgrade..?

Clive101, i'm on the opposite side of the fence on this one. In my view, you own one of the most beautiful pair of speakers in the world - and they should be paired with the best amps possible. If you can afford the trade-up to the 28 cubes then you should definitely do it. I agree with Elizabeth's point regarding the bass...especially since the MB2's dip down to the 20Hz range.
My goodness...i get chills just imagining the sensation of those lovely speakers with 28's powering them. You only live once, might as well light it up!

Here's a little vid posted just yesterday on the PS Audio site - on this particular topic.
http://www.psaudio.com/askpaul/high-power-amps/

Good luck 

TJ

[CanadianMaestro]

Better discussion of speakers/power, more rigorous:

https://www.crownaudio.com/how-much-amplifier-power

[clive101]

Thank you for the link but I think it is more to do with volume ( which I have plenty ) .
My issue is the sound quality and the gains from having a larger amp and not the volume, but interesting.

I have been looking a the specification of the Active version of my speakers.

https://pmc-speakers.com/products/consumer/se-series/mb2-se-active

Amplifier Power per Channel: LF 325W
MF 150W
HF 150W

Total 625 watts just wondering would that be the same as my 7b3 per channel ( 600 watts ) or does it not work that way as speaker cables etc

Need a bit more power to off set the speaker cable..? Separate amps in active speaker vs one amp..?