Hi DB, Your setup is fine. The PI models are what are known as input transformers, which have to be connected to the destination device (the device whose input they are connecting to) via a short length of cable, regardless of whether that cable is RCA or XLR. See the bold-faced statement near the bottom of page 1 of the manual, and the paragraph which follows it. Best regards, -- Al |
Al,
You wrote "That model would be located close to the amp, and connected to the amp via what must be a short XLR cable, and connected to the preamp with whatever length of RCA cable is required."
I have a pair of P1-XR ISOMAX units I've used to convert the XLR of an 18' cable from the processor to short RCA cable to a KEF KUBE near Proceed amps. My reasoning is to use XLR for the long cable run. Have I got that backward? The ISOMAXs removed an audible buzz encountered with a simple adapter. If I have it backward, then I'll just use RCA cables from processor to KUBE to amps.
db |
Following up on my previous post, based on the comments by Victor of BAT in this thread it appears that the concern I mentioned about possibly losing 75% of the amp's power capability when providing it with a single-ended input is not applicable to his designs, as they use differential stages, rather than independent paths for the two signal polarities. However, if you are providing the amp with a single-ended input via an adapter or adapter cable, you are reducing gain by 6 db, and you are most likely compromising sonics to a perceptible degree in several ways. The best way of interfacing your preamp and amp would be with a Jensen transformer, such as their model PI-2RX (similar to the model PI-2XX shown near the bottom of this page, except with RCA input connectors). Here is the datasheet. That model would be located close to the amp, and connected to the amp via what must be a short XLR cable, and connected to the preamp with whatever length of RCA cable is required. You should consult with Jensen by phone before finalizing selection of a particular model, though. Regards, -- Al |
If I'm not mistaken, your preamp has only unbalanced inputs and outputs, which does not seem ideal for use in conjunction with your fully balanced amplifier. For that matter, what is the means by which you are connecting the two components, as I believe the VK75SE does not provide unbalanced inputs?
If you are doing it with a simple RCA-to-XLR adapter or adapter cable, that is absolutely not ideal. Depending on the design of the amplifier, it might even result in putting no signal through one of the two balanced signal paths through the entire amplifier, for each channel. In that situation the result would be (among other things) a reduction of the amp's power capability that approaches 75%, reducing the amp's capability from 75 watts to less than 20 watts.
Also, a point to be aware of is that the 89.5 db specified sensitivity of your speakers is with respect to 2.83 volts, not 1 watt. 2.83 volts corresponds to 1 watt into 8 ohms, but it corresponds to 2 watts into the 4 ohm nominal impedance of the speaker, which means that their sensitivity is only 86.5 db for a 1 watt input. And as a tube amplifier, the BAT is not able to deliver significantly more power into 4 ohms than it can deliver into 8 ohms, being rated at 75 watts into either impedance.
Regards,
-- Al |
I'm puzzled. I don't see a separate DAC in this setup. If the DAC is what came in the Cary and thats circa 2001, then you are describing exactly the issue of an older CD player... same difference I hear comparing the analog outs of my Linn Genki (2001) vs the digital out from Linn to my DAC. Review makes the Cary sound like a wonderful transport so if it can feed digital to a DAC, that may be the cure. |
Im with Frogman. Good Luck |
To make sure you don't have impedance matching problems, try swapping in a SS amp with high input impedance and low output impedance and stable into 2 ohm loads.
However it is normal for music not to sound full and dynamic at lower than natural levels.
Play at correct volume or resort to mid-fi cures like equalizers or tone controls. |
How big is the room?
With a sensitivity of 89 dB and 75 wpc, plus 3dB for a stereo pair and another 2dB for room gain, this setup as is should be able to hit clean peaks around 112 dB at 1M away or 106 dB at 2M away. I like having 150 wpc or more, but I've heard very dynamic systems with middling sensitivity and 70 wpc in medium-sized (say 16x18) rooms. It helps when the system has a very low noise floor. |
Agree with Frogman...certainly worth a try first. some amps dont mono well...but most often those are the ones that are not designed to be used as such. sounds like the BATs might be designed for this, given that supposedly it is an quick internal switch/setup.
in any event, you should get some benefit from Frogman's approach...though if the BATs are designed for true mono...you should find that is even a step up (i am told...not actually compared myself on BAT). |
Sounds like a second 75SE is definitely worth considering. But, before
monoblocking them, why not try vertical biamping with two 75SE's; one
channel for the mid/low and the other for the tweet. Can't speak re these
amps specifically, and it sounds like Jfrech got excellent results, but it is
well documented than there are many examples of amps that when mono
blocked yield the benefits of the additional power, but also lose finesse
and purity. It may not be the case with these, but costs nothing to try first,
and is a simpler possible solution. And if you already like the sound of the
amps it can only be a step up; no risk of any losses. |
Broken,
Jfrech is one experienced guy, and sounds like he has actually done what i was suggesting with your amps. FWIW, i also have spoken to a former BBC engineer about my old CJ MV60s (55 watts/channel) when i was thinking of how to get more juice, and his description of what would happen exactly matches what Jfrech just described above...way, way better in all ways...more power, more control, superbly better bass damping, fuller soundstage, better macro and micro dynamics...
one to consider given that it sounds reasonably straight forward to do. |
Hi, yes the 75SE can be monoblocked to 150SE's. It's pretty easy, you can buy an internal kits (requires just a little basic soldering or external jumpers from BAT.
I did this a few years ago (I did post if you maybe search...sorry I don't have the links handy). I was feeling like my BAT 75SE was running out of gas with my Wilson Watt Puppy 6 and 8's at the time. It was distorting...more the soundstage collapsed some and dynamics (exactly what you're saying)
The second one is a big deal...it's not just more power, but it's better power..these amps now running each side of the amp in a balanced mode, lowering the noise floor, increasing the dynamics...it's just better + a lot more power and current.
If you love your amps, this is a good route to go...My issue was I live in Tx and my room upstairs couldn't handle the heat output....so I moved to Ayre MXR's. (another possible idea)
Hope this helps, good luck, you have a great system ! |
Can BAT75SE be monoblocked? you might ask...if so, try monoblocking them. depending on how the BATs respond to impedance, you could end up with 150-300 watts of power into your speakers. Some amps are designed for his, or are easily switched by a good audio tech...something to consider. |
More power baby!
My Dali Helicon 300 are powered with MC275 in mono-200 watts.
T |
to add to my post : more power would result in a tighter cleaner bass and mid bass which allows you to hear the great midrange more clearly on these speakers. I would highly recommend doing trials at home. |
The Dali 800 needs little power to get decent volume as they are reasonably efficient, but they sound better with powerfully amps controlling their bass drivers. Nice speakers in my opinion. |
Hi Broken
You have some very, very good electronics. The Cary, Audible Illusions and the BAT are all excellent pieces. I do not know the Dali, but read the specs.
It is a 4ohm speaker with 89db efficiency...and you are running 75 watts tubed. My guess is you could probably use a much more powerful amp and your speaker would probably respond well to it. Just a hunch...nothing more.
If you like your sound...but perhaps just need more fullness, dynamics, try a bigger BAT or you could try a big SS amp like a Pass amp. I think you might be very pleasantly surprised about how your speakers respond.
If you are looking for a serious ugprade which your system is capable of showing off...i would go for amp over power cords which are important but important as a 'finishing off' the system...they are not going to add something the equivalent of having 100-200 watts of more power. |
