RMAF: The Interocitor Saved My Life

[garylkoh]

Gary

Here is how I integrated the Tube Buffer into my system

http://forum.audiogon.com/cgi-bin/fr.pl?vaslt&1049587927&openflup&584&4#584

Excellent!! That is a brilliant solution to ensure that a second output from the Ref 3 does not degrade the primary output chain. If the Lamm has 41k input impedance, I'm sure you heard the insertion loss when you connected the Gothems with their 10k input impedance. In this case, the 470k Ohm input impedance of the Tube Buffer solves that problem.

See? I learned something every day.

 

[Steve Williams]

Indeed I did even though the techs from JL Audio said I wouldn't need one

 

[microstrip]

Indeed I did even though the techs from JL Audio said I wouldn't need one

I received a similar answer about connecting a JLAudio sub to my REF40 from their technical department . But I have tried loading the ARC REF5 with a 20kohm load in parallel using the second XLR output and the sound lost some freshness. I looked for audio step down transformers but all the quality ones also had around 10 kohm input impedance. Perhaps the Interocitor will do the job perfectly, but is is overkill to use it for such application.

As the inputs of the sub are buffered I am almost sure that a few resistors and a soldering iron can solve the problem ...

 

[garylkoh]

I received a similar answer about connecting a JLAudio sub to my REF40 from their technical department . But I have tried loading the ARC REF5 with a 20kohm load in parallel using the second XLR output and the sound lost some freshness. I looked for audio step down transformers but all the quality ones also had around 10 kohm input impedance. Perhaps the Interocitor will do the job perfectly, but is is overkill to use it for such application.

As the inputs of the sub are buffered I am almost sure that a few resistors and a soldering iron can solve the problem ...

Microstrip, if you are using it only for subwoofers, try the Rane Balance Buddy - that's what I used in my home theater system for LFE, and I didn't notice any degradation. The Interocitor is way too expensive for this application.

 

[garylkoh]

This is the one I have:

http://www.rane.com/bb44x.html

 

[Gregadd]

Is the glass half full or half empty?

You arrive at the show and lo and behold you are sharing a room with the guy that has the perfect solution to your unexpected problem.

Go buy a lotto ticket.






powerball ticket.

 

[microstrip]

Microstrip, if you are using it only for subwoofers, try the Rane Balance Buddy - that's what I used in my home theater system for LFE, and I didn't notice any degradation. The Interocitor is way too expensive for this application.

Gary,
Thanks. I have now received a pair of Jensen JT-10KB-DPC step downs - they look quite similar to the device you are referring. This type has an impedance of 42 kohm loaded with 4k3 ohm - and the impedance will increase when loaded with 20k . I still have to mount and measure them when used in atypical conditions - I will report after I reach some conclusion about them.

 

[garylkoh]

Gary,
Thanks. I have now received a pair of Jensen JT-10KB-DPC step downs - they look quite similar to the device you are referring. This type has an impedance of 42 kohm loaded with 4k3 ohm - and the impedance will increase when loaded with 20k . I still have to mount and measure them when used in atypical conditions - I will report after I reach some conclusion about them.

That should work well - although if you don't need the step down and are only using it for subwoofers, JT-112P-2HPC might arguably be better.

 

[LL21]

Excellent!! That is a brilliant solution to ensure that a second output from the Ref 3 does not degrade the primary output chain. If the Lamm has 41k input impedance, I'm sure you heard the insertion loss when you connected the Gothems with their 10k input impedance. In this case, the 470k Ohm input impedance of the Tube Buffer solves that problem.

See? I learned something every day.

ACtually, i am a bit remedial here...my CJ GAT is SE only and runs SE outs to the Velodyne DD18 (47kohm impedance) and Gryphon amp (20kohm impedance). The output impedance of the CJ is 100ohms. Am i okay here?

 

[garylkoh]

ACtually, i am a bit remedial here...my CJ GAT is SE only and runs SE outs to the Velodyne DD18 (47kohm impedance) and Gryphon amp (20kohm impedance). The output impedance of the CJ is 100ohms. Am i okay here?

I think that you might have had the same problem as Steve had without the tube buffer. The addition of the Velodyne would degrade the sound of the Gryphon. It won't be as bad, but 47kOhm and 20kOhm are too close.

 

[LL21]

Interesting and good to know...i have not tried the system without the sub. i am expecting my Gryphon to come in on Friday (just using a loaner amp right now...20 yrs old and dont even know what its input impedance is)...i will try with and without sub hooked up to CJ pre and report back. thanks. (BTW, what is supposed to happen when i put sub in the system?)_

 

[garylkoh]

Interesting and good to know...i have not tried the system without the sub. i am expecting my Gryphon to come in on Friday (just using a loaner amp right now...20 yrs old and dont even know what its input impedance is)...i will try with and without sub hooked up to CJ pre and report back. thanks. (BTW, what is supposed to happen when i put sub in the system?)_

Soundstage shrinks, you lose clarity and detail.

 

[LL21]

Eeeks...thanks Gary. FWIW, i did not notice any major changes to soundstage/clarity/detail when i would turn off the sub (but leave it connected to the preamp). If anything, i felt the soundstage was superior with the sub in-place and playing. Do i actually need to unhook the SE RCA between the Pre and Sub (even if i turn off the sub)?

 

[garylkoh]

Eeeks...thanks Gary. FWIW, i did not notice any major changes to soundstage/clarity/detail when i would turn off the sub (but leave it connected to the preamp). If anything, i felt the soundstage was superior with the sub in-place and playing. Do i actually need to unhook the SE RCA between the Pre and Sub (even if i turn off the sub)?

Turning off the sub without unplugging it might be even worse than having it on..... The soundstage is always superior with a well-integrated sub in place. It's the long wavelengths that give you the wide soundstage and ambience.

 

[microstrip]

I think that you might have had the same problem as Steve had without the tube buffer. The addition of the Velodyne would degrade the sound of the Gryphon. It won't be as bad, but 47kOhm and 20kOhm are too close.

Gary,
Although it is has tubes the cj GAT has a solid state buffer and is prepared to drive low impedance amplifiers - I think it will not have problems driving the parallel charge.

 

[LL21]

Thanks for helping out Microstrip...i am starting to get a picture of what you are all discussing with my very rudimentary understanding. Yes, i recall now that CJ has specifically stated that one advantage of the GATs design is exactly as you describe above in terms of the design's ability to drive to different cables, lengths, impedances, etc.

 

[garylkoh]

Gary,
Although it is has tubes the cj GAT has a solid state buffer and is prepared to drive low impedance amplifiers - I think it will not have problems driving the parallel charge.

Thanks, micro. That may explain why I've been reading over and over again that cj are sounding more and more solid-state. IMO a lot of the "tube sound" comes from the high output impedance of some tube preamps. My preferred tube pre and design reference is a 40lb transformer-output beast with high-impedance and low-impedance outputs. I learned a lot listening to the two outputs driving various input impedance on the power amp. It turned out super-high input impedance is not a good thing, and super-low output impedance is not a good thing either!

 

[garylkoh]

Thanks for helping out Microstrip...i am starting to get a picture of what you are all discussing with my very rudimentary understanding. Yes, i recall now that CJ has specifically stated that one advantage of the GATs design is exactly as you describe above in terms of the design's ability to drive to different cables, lengths, impedances, etc.

At that price level, the GAT might even have two output buffers if it has two outputs instead of just one buffer and a Y-splitter internally. If that's the case, then my comments don't hold water.

 

[MylesBAstor]

Thanks, micro. That may explain why I've been reading over and over again that cj are sounding more and more solid-state. IMO a lot of the "tube sound" comes from the high output impedance of some tube preamps. My preferred tube pre and design reference is a 40lb transformer-output beast with high-impedance and low-impedance outputs. I learned a lot listening to the two outputs driving various input impedance on the power amp. It turned out super-high input impedance is not a good thing, and super-low output impedance is not a good thing either!

Owning both, I would disagree Gary But something like the GAT is less forgiving than the ART preamplifier. In other words, one hears more of the individual character of each recording rather than all recordings sounding alike (something that I find many SET amps do).

Rather than sounding ss, the newest cj amps/pre sound more neutral and like music eg. they retain the tube sound while reducing the euphonic caramelish cj stereotypical coloration.The latest cj efforts are far more transparent and extended at the frequency extremes; OTOH, you still have that wonderful harmonic tube envelope, palpable three dimensionality of instruments as well as unsurpassed abilty to resolve recording space eg. ceilings and walls The magic is in part due to those Teflon caps. Beasts to break in but once cooked, sound wonderful.

 

[SMcAudio]

The Interocitor One saves the day again!

Hi Folks,

It's my first time on the forum, so I extend my greetings to all. Gary Koh was nice enough to start this thread (but then he's a very nice guy) when I brought the first prototypes of the Interocitor to RMAF. Since then I have developed the production design and brought the first production units to THE Show in Las Vegas where I demoed them in my exhibit room along with The Lotus Group (distributor for my VRE-1C preamp) and the WAVAC folks. This turned out to be the most expensive system I have ever worked with - on the plus side of $400K! It also turned out to be among the more complex arrangements of amplifiers I have encountered because of the tri-amped Granada G2 speakers from The Lotus Group. This is a phenomenal speaker that is driven by an active, 3-way, DSP crossover, with ICE power modules (500W each) included in the DSP box. All cabling was by Pranawire, and my VRE-1C drove the system, and was fed by a WAVAC phono stage, EAR Acute 3 disc player, and a file server connected to the EAR's USB input.

This system was quite complex and difficult to set up, and one of the problems was a ground noise issue caused by the multiple amplifiers and DSP box being connected (necessarily) to multiple AC circuits. Everyone involved did their best to come up with a connection arrangement that would eliminate the ground noise, but it resisted all attempts and the situation looked bleak for quiet operation. Interocitor One to the rescue! This is exactly what the Interocitor was designed for (one of its many uses) and it did the job perfectly. Grounding issues were eliminated and the system was dead quiet and sounded excellent - success! Joe Cohen (of The Lotus Group) decided that the Interocitor One was like a "Swiss Army knife" for high-end systems - meaning that it was a sort of general-purpose tool that could come in handy for solving a variety of problems. He's right!

I had hoped to include some photos of our show system and the Interocitor One in action, but I see that I'm not quite prepared for that yet. Feel free to contact me directly for more info, and of course I will do my best to answer any questions that may come up.

Best regards,

Steve McCormack
SMc Audio