The ohm meter across does not work. I tried, one answer was "all you are measuring is the woofer dc load". All I can say is it does not work.
If you like Bryston, I don't think you can go wrong with the 14b sst. If you clip this, you need help.
Honestly thou, this does not make much sense to me but, I was talking with a Bryston Dealer who also sold Simaudio and he said that he has clipped a 14b but never a large Sim model. I dunno, larger profit margin?
Marty |
Thanks for all the info...
My Kefs 104.2 are rated at 4 ohms,92 db,can I not put a ohm meter across the posts,on one speaker at a time,and measure the actual ohms while playing at different volumes?
This would certainly help eliminate some of the guess work.
The red light appears at 1-2 o'clock position.Never do I go above 2 o'clock.
Why so loud you ask,when we entertain and are in the kitchen ,this volume is needed to maintain the party atmosphere in the kitchen,some distance away.
The volume is loud but not earth shattering.
My speakers are 16 years old..
Maybe a dedicated outlet...
I am going to sell the 4B ST and buy a 14B SST,for sure.
That is as good a place to start as any.Don,t you think?? |
Weird, I started to have this same basic problem with a 9B. I went round and round with Byrston, my dealer and the speaker manufacture. Conclusion, I was under powered. I still think this was bull.... But hey, they know more than I do. The drop in speaker impedance was always in the back of my mind, just nobody said this could happen. They suggested I physically inspect the crossover, looks for burn marks, no luck. A 4b is a much larger amp, thou.
I doubt their is anything wrong with the amp. One interesting comment form Bryston was the their amps either work, or they don't. No middle ground. I also think their amps work great, in their design parameters. The 9b is stable to 4 ohms, not 3.9999 ohms. The speakers I am using stay under 4 ohm for everything under 650hz, a major fundamentals section of the spectrum. The 4b should be stable down to 3 ohms(their quote).
Also the "cleaner" the power I feed the amp the higher I could push the unit. Dedicated line, ps ultimate outlet and Richard Gray seamed to help raise the limits, but did not fix the issue. So I bought a Simaudio Titan, I no longer have an issue.
Another 4b is cheaper, but I once heard that a bridged amp never sounded "better" than an unbridged amp. Plus I don't know how much a 4b bridged would like a 4 ohm load.
Good Luck,
Marty |
Check your AC voltage, it may be too low. |
I've owned the 4bst and 7bst and found that the former could play very loud without red lighting. I liked the sound and punch better with the 7bst regardless of usual listening volumes. I can't recall turning my preamp up more than the 1 o'clock position since it got really loud much before that.
It didn't occur to me before, but you said that the problem is only recent. Two questions: 1) Does your orange (or is it yellow?) light come on before the red does? 2) Does everything sound the same before as it does now? Maybe your warning light system is bad. If you are listening at the same volumes (both position on the dial and perceived db level) as before and the only difference is that the red light comes on now, maybe it's the light. You might want to ask Bryston about that. Also, you might want to carry the 4bst to a friend's place or your dealer and plug it into his/her system. See if and when the light comes on there? If the amp's OK somewhere else, maybe the speakers have a problem and the impedence has dropped. Just a few thoughts. |
First of all how hard are you driving the system? Do you turn you volume above 3 o'clock?
Did you check if your speakers can handle 600W/ch(I believe that bridged Brystons 4b-st through such wattage in 4Ohm or even more)? |
Bryston replied "very unlikely that there is a fault.Amps usually work or they don.t.
I guess I'm under powered or need hearing aids. |
Yep, the truth is there that your unit needs to be checked.
Good to have 20yrs transferable warranty though! |
My speakers are Kef 104.2..92 db..4 ohm and they have a single binding post only.
I have contacted Bryston,regarding this problem,on the off chance there is a technical fault.
Haven't heard anything yet.
Thanks ,so far, for the info. |
Richard,
First we've got to make sure that the author's speakers are bi-wirable. Second we need to know what kind of speakers are we talking about that even Bryston 4b-st doesn't have enough current to swing a woofer(is it some 1000W woofer??)
7b-st as suggested by Ozzfly is basically the same thing as 4b-st but made as a pure monoblock and certainly sounds better than bridged pair of 4b-st. Thus in the case with Bryston and with most brands it's much better to go for dedicated monoblocks instead of using bridged pair.
And at last the question:
If I have amp 1W/ch and I want to use a bridged pair will I add 3dB to the volume?
I guess not! The whole different issue when you double 250W/ch or 200W/ch isn't it? |
I disagree with Markanetz's general statement concerning monoblocks being better than bridged. Different brands act differently.
Although not knowlegable about Bryston, when you bridge them, they kind of become monoblocks. I personally am familiar with the now discontinued Cello products, and in my opinion, the bridged set of the Performance amps blew away the nonbridged setup.
I think I would TRY biamping with another 4B ST stereo amp. You could try horizontal or verticle biamping as well as bridging them.
Also remember double your power only adds 3 db to the volume. If you amps are clipping, this probably won't solve the problem.
Good luck and have fun.
Richard |
I was in the same situation in that I also wanted more power from my 4BST. My speakers were PSB Stratus Gold Is. I went with a Spectron Musician II (500 watts per channel) and could not be happier. Not only did I have more power, the sound quality was far superior. I found the 4BST too bright, unnatural sounding and less detailed in comparison. I have since upgraded my speakers to Silverline LaFolias and the Spectron is a perfect fit.
Unlike Bryston, Spectron had some prior production problems which gave them some bad press. I have had mine for 8 months and have had no problems. I hear that the newer Spectrons have better quality control. I was willing to trade off built like a tank Bryston, but not nearly as musical, for a Spectron Musician II that didnt have quite the same build quality as my Bryston, but sounded far superior.
Finally, I have no affiliation with Spectron. Im just a very happy customer who would like to share my thoughts. Good Luck! Happy Listening!!
Jim |
If you are happy with the 4B-ST, I too would suggest a pair of used 7B-ST's (what the heck, a 20 yr warranty). The 4B-ST will not give the same performance level on a bridged basis. If you like to listen loud, you will be hard pressed to find more performance for the dollar (i.e., quality reproduction, not just volume). I am also not affiliated with Bryston but sure do enjoy their stuff. Happy listening! P.S. I didn't know about their SST series so can't comment on that (thanks for the heads up Pbb). I guess their next upgrade will be SSST ;-) |
What do you mean "It doesn't have to be Bryston". Keep Canada green, get Bryston. 7B STs is the way to go. Why, anything else (unless it's Simaudio. etc.)simply isn't Canadian.
No I have no relation with Bryston, other than being a satisfied customer. They no have an SST series BTW, for those who must have the latest. Don't forget the music. Good day. |
Do you mean that your 4B-st were clipping??? With what speakers???
Dedicated monoblocks will definitely do the job better than bridged amplifier.
If you somewhay sacrifice quantity over the quality you won't go too far away towards higher budjet over getting another 4B-st.
For example most-likely if you get VTL MB225 you will stay with the same power and you won't be red-ligtning. |
