Wow! Thanks. I'll check it out.
Different gain on 2 amps.
I never posted before. OK, here's the deal. I have a new VAC preamp that has no tape monitor output. Only outputs are after the volume control. I want to feed the output of the preamp into 2 separate amplifiers. One to feed my listening room speakers, and the other to feed a second power amp to drive some nice MB Quart speakers in my kitchen. I have done this before using the tape monitor out to a second preamp, then to the second amp and on to the kitchen. Separate volume controls, no sweat.
Now I have a very nice VAC Phi 200 tube power amp for the listening room. Gain is 37 DB for Single ended RCA's. The other amp for the kitchen is a solid state CJ amp with a gain of 27. So I connected these 2 amps to the 2 outputs from the VAC preamp. Everything works, except the volume in the listening room is way louder due to the difference in gain of the 2 amps. As we all know, putting the signal into another preamp is no help.
2 questions:
1. Any ideas on how I can boost up the preamp output from the VAC preamp to the CJ power amp so as to equalize the volumes in both rooms?
2. Anyone know a reasonably priced amp with a gain of 37 or close to that?
BTW, I don't/can't just buy another VAC tube amp for the kitchen. Way too big, way too expensive.
Now I have a very nice VAC Phi 200 tube power amp for the listening room. Gain is 37 DB for Single ended RCA's. The other amp for the kitchen is a solid state CJ amp with a gain of 27. So I connected these 2 amps to the 2 outputs from the VAC preamp. Everything works, except the volume in the listening room is way louder due to the difference in gain of the 2 amps. As we all know, putting the signal into another preamp is no help.
2 questions:
1. Any ideas on how I can boost up the preamp output from the VAC preamp to the CJ power amp so as to equalize the volumes in both rooms?
2. Anyone know a reasonably priced amp with a gain of 37 or close to that?
BTW, I don't/can't just buy another VAC tube amp for the kitchen. Way too big, way too expensive.
13 responses Add your response
Front end: My source the VAC phono stage included in the Ren 5 preamp. I have an SME model 10 table with a series V tonearm and a second arm which is a 309. Ortofon MC Anna Cartridge on one arm and a Kiseki Purple Heart on the other. Analog all the way. 1200 vinyl records. I must point out that I love to cook (is that so wrong?) so I want, must have, good sound in the kitchen. I like to make rack of lamb with Pinot Noir sauce. The sauce takes one hour to make, mostly stirring. Jazz, classical and great vinyl rock. For me, good sound in the kitchen is a big deal. |
I should have asked that. What IS your source anyway? You would find a much easier time with a Roon enabled player or something that had nothing to do with your main pre-amp/amplifier. at all. I use this kind of arrangement with Logitech Media Server. I can keep the music in sync in my living room and home office digitally. Best, Erik |
1. Any ideas on how I can boost up the preamp output from the VAC preamp to the CJ power amp so as to equalize the volumes in both rooms?Like I said put a Schiit Sys passive on the amp/speakers that's loudest, and drive the passive with the Vac pre, so you can equalize both when driven by the Vac pre. Cheers George |
The Schiit Sys is a nice passive volume control, but a Lightspeed attenuator is more transparent. Shameless plug for George who makes them, but I've tried both and if you need to lower volume in your main system you want something better than a Sys considering the quality of your amp. The Lightspeed is a couple hundred dollars more than the Schiit Sys. I find it to be extremely transparent and the price point is very good. |
Thanks everybody. I was hoping that could do something to the signal going to the lesser amp rather than messing with what is going to the VAC Phi 200. I saw a device at Amazon called an iBoost 800. Wondering if anybody has seen/used one of these? https://www.amazon.com/iBoost-800-Stereo-Amplifier-Booster/dp/B00CVDN2O0/ref=sr_1_1?ie=UTF8&qid=... The diagram shown on the Amazon website shows it used to boost the signal for a very long run of cable. Also, the comments show that some people use it to boost signal to a subwoofer. These devices are pretty cheap and I will probably try the Shiit Sys and the iBoost. |
The issue is more than gain of the amps, but also sensitivity of the speakers. :) In typical audiophile fashion, you should get less sensitive speakers for your listening room. :D :D :D One thing to watch out for though is tube preamps don't like to split their output. You could be doing your listening room a disservice by trying this. Best, Erik |
@otto1234 Just use a Shiit Sys for $49 on the input of the highest gain amp. That way you can balance them both perfectly to your own ear. http://schiit.com/products/sys Cheers George |
Yes, consistent with Alan’s suggestion consider putting a pair of Rothwell 10 db attenuators at the inputs of the Phi 200. More than a few members here have used them, with some (including me) having found them to be very transparent, although some others have reported them to result in compromised dynamics or other sonic issues. My suspicion is that a reason for the discrepancies in these reports is differences in the input impedances of the components with which they are used. While the input impedance of the Phi 200 doesn’t appear to be specified, I suspect that it is high, which figures to increase the likelihood of success with passive attenuators such as these. Regards, -- Al |
