I don't know the details of course, but it is possible that the crossover's volume control is right at the input. This might mean that the setting you've found is a better load for your preamp (listed as having a 1000 Ohm output impedance - high enough to make loading issues a consideration), thus giving you better dynamics. At least you were able to find an arrangement that works well for you.
Burmester 911 mk3
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Hi Steve,
Yes, thankfully I was able to solve the issue without swapping gear. The sound was not bad before but this did help dynamics and punch a bit. After hearing your demo I realized my system was lacking some in the dynamics department. I do wonder how the SMc VRE-1C and the Burmester 100 phono stage would sound in my system, but even after selling my existing gear I would be quite short of funds if purchased new.
Best Regards,
Sean
Hi Gary - what does this mean in terms of Interocitor and its application to my system? CJ GAT to Gryphon Colosseum? At the moment, i have cables RCA-XLR terminated...and even compared to my old TA Ref ICs (which had a little buzz), these cables make the system dead silent even though my Wilson X1s are 95db efficient. i think the CJ gain is 28db and the Gryphon is 31db or something. So i feel very fortunate to have a dead silent system. Even with tubes about 700 hours...i need to stand directly in front of the tweeter (not off-axis which is silent) by about 7 inches to even begin to hear a slight whisper of tube. And in truth you really only hear it within about 3 inches.
Does this mean dont bother with Interocitor?
Loyd,
What are your typical listening volume settings with the GAT? IMHO you have to try - using the Interocitor you could connect the GAT to the XLR input of the Colosseum in true balanced mode - this can be great with some balanced inputs. But you would need the model with male XLRs.
Hi Lloyd -
Nice to hear that your system is working well. The GAT is an excellent preamp, and the Gryphon Colosseum is an extraordinary amplifier! But the Gryphon is another instance of an amp that has been designed to be driven with a balanced input signal. Your RCA-XLR terminated cables allow the system to operate, but you are running the amps with an unbalanced input signal. While this does work, it suggests that you may be missing some of the full performance potential of the Colosseum amps. The Interocitor / Flex-Connect allows you to create a true balanced connection between your preamp and amp. Another consideration is system gain. Both your preamp and amps have high gain and your speakers are fairly sensitive, so the -12dB attenuation of the 4:1 Flex-Connect model may actually help to optimize the preamp / amp interface and improve your system signal-to-noise ratio. Ground isolation can also improve low-level dynamic expression and the "blackness" of your background. Impedance matching does not appear to be an issue for you, so you would also be a candidate for the new, adjustable-ratio Flex-Connect model, set for (most likely) the 2:1 mode.
As you have pointed-out, your system is working well as-is and you may be perfectly happy. On the other hand, you have an exceptional system, and if there is a relatively easy way to take its performance to even higher levels, it might be worth exploring. One note about cables: if you do try the Flex-Connect, my suggestion would be to use a short pair of RCA-RCA unbalanced cables from the GAT to the Flex-Connect, and then whatever length of balanced XLR cables you need from the Flex-Connect to your amps.
garylkoh
WBF Technical Expert (Speakers & Audio Equipment)
Some Interocitation might still be beneficial as it sounds like according to joeinid the GAT sounds better working with the volume control at about 12 o'clock. I've found in general the vast majority of preamps sound better when the volume control is not at the extreme low (even those with stepped discrete resistor attenuators). May be someone who knows preamp design much better than I can chime in on why this may be so.
garylkoh
WBF Technical Expert (Speakers & Audio Equipment)
I absolutely love what Steve's Interocitor, err Flex-Connect, is doing for my GAT with the 911mk3's. It is even beneficial running between my GAT and CJ Premier 350 amp. I was immersed in the music last night enjoying the heck out of my system. I will not be without it now!
In my system, I get far more enjoyment from better sound with my Burmester 911 MK3 to Concert Fidelity CF-080LX using xlr-rca interconnects ( and Wadia S7i) than with my previous Burmester 089 (or 069) going direct XLR to my 911 MK3. More transparancy, detail and decay. Go figure.
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Direct quote from Audiogon and an A/V dealer:
"09-20-11: Clio09
I have just received some information regarding the output impedance of the Concert Fidelity CF-080 that should put the discussion to rest. According to the designer, the 33k ohm output impedance is an incorrect assumption. In addition to the tubes, the circuit design uses a capacitor and a resistor at the output to prevent harmful DC signal to be transmitted to the power amp.
So the actual measured output impedance, which depends on the frequency of the CF-080, is between 5.2k ohms and 900 ohms as measured between various points within a frequency range of 20Hz to 20kHz.
From this I would say that the CF-080 will match up just fine with most power amps out there. This includes the Concert Fidelity amps with 47k ohms input impedance. Not that this was ever in doubt from my perspective having heard the system multiple times and regarding it as one of the best I have heard.
I fully trust this information as it came from the designer himself. As such I don't feel there should be further debate on the subject."
Jim, what about going direct to the 911 with the Wadia? It seems to be up to the task of driving the power amp; the output voltage can be set to match the sensitivity of the system and it incorporates a well implemented digital volume control. I have read an account of someone who has tried 3 different preamps with this unit and prefered direct connection every time.
To most people that output impedance would cause some alarm bells to go off. But of course we have learnt that the impedance matching rule of 1:10 is not right.
Alarm bells? Much more than that - if we use the 1k RCA input impedance value measured by AndromedaAudio this means that when you connect the CF80 to the 911mk3 you get a variation of frequency response of 9 dB due to the output impedance of the preamplifier!
BTW, this so called "rule" does not cover preamplifiers with capacitor coupling, as they usually only specify the output impedance at 1kHz.
Because the Concert Fidelity CF 080LX is the best preamp I have ever heard, bar none. And partnered with a SS amp, cannot be beat in my system, including using Wadia direct to 911 MK3. This is all after extensive listening sessions.
Jim, how would you describe the differences between Wadia -> 911 and Wadia -> CF -> 911?
Yes, I sell it with a 2-week, money-back guarantee - you just cover the shipping if you decide to return it. I am in the process of finishing the production design change to the "Flex-Connect" name, along with a slight change to the chassis. The new model will be available shortly, in about 2 or 3 weeks. I do plan to make it available through retailers nationwide as soon as possible, but that is a process that takes some time. For the moment, it is available from me directly.
Nice! Looks like we should be in touch in about 2-3 weeks or so! That works for me...we've got a few things going on here anyway.
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