2. amps-preamps
  3. 191434-23267

What Power Amplifier Should I Buy?

I am looking to increase my system power. I currently am using a Bryston 2.5B cubed, which is specified at 135 Watts/CH. I am using Revel f208 speakers crossed over at 120 Hz to a 15" HSU sub. The f208 speakers have 88.5 dB sensitivity (Amir measured 88-89dB SPL at 1W into 8 ohms). I sit about 7.5 feet away from the speakers and listen up to 92 dB SPL, but mostly stay between 80-90 dB SPL at my listenin g location.

I have not had power issues. I've never seen a clipping light. I just want more oomph. I've never had a power amp with more power than the 2.5B cubed.

My budget is about $5K. I have been looking at some used 4b cubed amps.

My preamp is a vintage ML No. 38s. Digital from Bryston BDP-3/BDA-3 combo. Analog using Koetsu RS and Shelter 901 cartridges into an SUT (20x) followed by a very vintage Paragon System E used as a phono preamp (I have fully repaired this preamp, particularly the power supply).

I like the sound of the 2.5B cubed. I had a Cary 120 tube amp for some time, but grew tired of the heat and the continuous maintenance, including the insane prices for tubes. I did not experince that great "tube sound" that others rave about. I sold the Cary and went back to the 2.5B cubed.

Will the 4B cubed disappoint?

What other amps should I consifder, new or used?

Thanks for your help!

 

128x128Ag insider logo xs@2xkevemaher
kevemaher's avatar
Ag insider logo xs@2x
kevemaher OP
85 posts
 

@jaytor Yeah, I have always had concerns about the EQ. But some form of EQ is needed to help tame some of the FR variations from the room.

I have traps which are very effective. I don't need more, except for the floor to ceiling mode. But the "rules" prevent me from doing that. I have worked very hard at positioning the speakers and the sub to get the best FR, but there are still +/- 6 dB variations in the bass. I am restricted to near the present locations. I have tried a miniDSP Flex. It doesn't affect the time domain at all and is barely better than the analog EQ. I ditched that. And I enjoy the idea that I have an all analog signal path (except for the CD/DVD and music files).

So the dBx EQ is a somewhat "necessary" evil. I could live without it, but the engineer in me strives to have as perfect FR and TR (Temporal Response) as I can manage to obtain.

The XO does a very good job, far better than the Rane I once used. I don't like the idea of running the f208s full range and band limiting the woofer. However I haven't tried this in a while. Might be worth a shot.

Are you aware of any reviews on the Sublime XO?

Very helpful advice. Thanks.

jaytor's avatar
jaytor
761 posts
 

@kevemaher - I suspect the crossover is not the biggest issue. I actually own a Sublime K235 (their newer model) and it seems pretty good although I don't currently have in my system. The graphic equalizer has many more lower-quality op-amps and capacitors in the signal path, so I think this is probably the bigger issue. 

If you really need equalization, I'd suggest looking for a decent DSP preamp, such as the Anthem STR or DEQX Pre-4.

Another option is the Danville Signal DSP Nexus. This isn't quite as fancy from a case-work perspective, and the software is quite complex (but there is good support), but the sound quality is pretty good using the latest AKM DACs. I also have a DSP Nexus 2/8 that I've been playing around with. 

And then there are the Trinnov systems although I don't know if their products support a phono preamp or even analog input.

kevemaher's avatar
Ag insider logo xs@2x
kevemaher OP
85 posts
 

After all this discussion of power, I bought a Bryston BP-17 cubed preamp. I'll get it next week. This discussion has convinced me that I have enough power from my power amp. So I decided to see if the much newer BP-17-3 can outperform the aged Levinson #38s. I hope so.

More to discover