Help choose best amp/preamp combo?

I did try it plug in the wall power jack but I still don"t feel any different.What is you guy think?

Hi every one
I need some advised or opion from you guy.That I heard some one said that if you plugs in power cord from Amplifier to wall power jack will produce very good sound compared to if you plugs amp power cord to condition power cleaner filter.Is this right?

Hi lucky, glad you found a solution for you system, and yes, the P7 sounds very good with the A21.  I would say it's on the warm side a little.  Recently I upgraded my car system and can hear highs/cymbals more clearly in the car, so it is a little brighter in the car, but not harsh.

I'd love to try the JC pre one day!

I'm glad that you had a great experience with the JC2!  Enjoy!

Finally I want to Thanks and Appreciate to all Audiogon member and special Thanks to Auxinput,213 runnin, frozen tundra Andrei_nz and Erik_squires for helping me at the begin until I found a right preamp for A21.You guy are awsome.Bye Guy.

A21 +Jc2 vs Rotel 1582 Mk2 +Jc2 side by side test I would say both of them have a different sound.Both have warm sound ,Detail ,clear, tight bass..,Only the different is A21 sound is more wide open and juicy compare to 1582.but I do love the sound from both of them.Both A21 and 1582 Mk2 is very good amp to own.that is my opion.

I did test A21 + Jc2 couple days ago and I would say: JC2 is perfect matches with A21.It is really made my 805 speaker sing. Sound too good to be true. I can"t image that a preamp is so important in sound field until I got Jc2. Sound is clear transfarent , warm sound but sweet.sound very detail and juicy especially in bass is very tigh and powerful.I am in heavens now.JC2 is worth every penny I spend.

Helo 213runnin my system below:
Para A21 + Jc2 and pair B&W 805 + JBL se2500 (400 watts) sub.Oppo 103 DVDs player.Iused RCA Mit cable branch for the system and sound good.how about your A21 +P7 ? Is this good match? Does it sound warm?

Please give me time.I will do side by side test on A21 +Jc 2 vs rotel 1582 + jc2 and 1582 + xsp1 vs A21 + xsp1.so far I test Rotel 1582 + xsp1 vs A21+xsp1 there is no big different but 1582 produce a warm sound compare to A21.I would say 1582+xsp1 is good matches.sound warm and comfort sound.i like it better than A21.

luckyrainbow - hopefully you have resolved the volume issue with the sub.  Have you had a chance to form an opinion on the Parasound JC2?

I do used xlr cable for amp and used Rca cable for sub.because my Jbl es2500 subwoofer not carry xlr in/out put.rca only.

"best amp/preamp combo?"

The best combo for amp/preamp should be designed and engineering by the same team.  Made by the same manufacture, same generation and same era.

Lucky, good find on the JC2!  I've got the A21 with a P7 from Parasound.  I concur with auxinput that you only use the Main outputs of the JC2 for the A21.   

Hopefully you have XLR cables to go from the JC2 output to the a21 inputs?  They look like this:  
https://www.amazon.com/AudioQuest-Diamondback-audio-cable-stereo/dp/B000ETSYUK/ref=sr_1_3?ie=UTF8&am…
Also, could you list what brand speaker and RCA cables you are using now?

Lucky:

You are not so lucky looking for the warm, lush and full sound.
I am working on that issue currently & it's a whole big learning curve

My thoughts are to start with cheaper options first

1st)  try electrical outlet upgrade and/or power cable upgrade
        It really does make a difference $200_$500
2nd) try a good high end OF between other and power amp
        $300 or,so 
         SPEAKER CABLES GET REAL PRICY

Then evaluate the changes, you will be surprised!

Ps: Just got a Pass Lab class a from a class d amp ( the class d actually sound like a parasound) The pass really does what people say and gives you the full & tonally rich sound

Good luck, you'll need it

Jeff

No.  Do not use the "Record Out'.  Only use the "Main Outputs".  I took a look at the manual and it looks like there are 2 Main Outputs.  One XLR and one RCA.  You should be able to use both.  XLR for the amp and RCA for the sub. 

You mean use Y splitter in order to split in 2 then I apply both "rec out" instead of one rec out like what I do right now?

The "record out" on the JC2 is not meant to be a normal preamp output.  It is outputting the signal at full level.  There is no "volume" adjustment for this.  The "record out" is meant to be used by a recording device (like tape recorder).  I missed the fact that you are using a JBL sub.  You will probably have to buy a "y splitter cable" so that you can use the same output on the JC2 for both the sub and the A21 amp.  It's best to get an XLR splitter cable, and then get an XLR-to-RCA cable for the sub.

I did fixed the problem by adjust the "gain knob" from rear a21 to 12 o'clock and sound back to normal but bass still powerful. I have to adjust the knob from sub to 9 instead of 12 like normal from xsp1.

I just hook up a21 to jc2. I don"t know some thing wrong on it.I hear the huge bass from sub coming out and sound from both BW 805 so small like sound sinking? I hook up sub cable to rec out on rear Uc 2 is this wrong? Some one help pleasant.

Hi luckyrainbow.  I have the B&W 805 Diamonds and they are excellent.  They are very warm and full bodied.  Also, a lot of bass for such a small speaker!

I would be interested to see what you think of the Rotel rb1582.  The Rotel equipment is like an Emotiva that has higher quality components (capacitors, op amps, etc.). I suspect that the Parasound A21 is going to sound warmer then the Rotel because the FET input stage is fully Class A and the output stag is biased into Class A for the first 8 watts.  The Rotel is only Class AB.  THe Parasound also has bigger power supply.

Now I have Rotel RB1582MK2 just bought and not test yet.and my Emotiva Xsp1 gen 2 need to get rid.1582 mk2 is 4 months old and  Emotiva xsp1 is two months old.Any one need it just shoot me email luckyrainbow63@yahoo.com Thank you you guy

Thank You for your good advised Auxinput & Andrei_NZ I will listen to two of you guy by keeping A21 and Just found a good deal on JC2 for 2060 used.the Jc2 will deliver on this Friday.I will test it and let you guy know the result.Thanks again

If you want to know what a preamp is and what one can do for you, read on. You’ll find answers to all your questions about how preamps works, the various types that are available, and which preamp will be best for you, your budget, and your music.

Usually any impedance over 10k is considered high and acceptable by most preamps. The more sensitive preamps will start to roll off high frequencies as the amplifier impedance drops or the volume control is changed.

This statement is not correct! For example ARC recommends the amplifier input impedance be no lower than 30K. In any event, if the preamp does not like the input impedance because its too low, bass will suffer at any setting of the volume control.

This is moot if the Parasound stays and I agree with others that it is the better amp over a Rotel! It has a high enough input impedance that most tube preamps will be fine with it. There are balanced line tube preamps; we make some, so does BAT, ARC and others.

I will also vote for a new preamp.  Many people suggested tube.  I would suggest looking at a Class A preamp (Krell or maybe Pass Labs, maybe even Parasound JC2).  The FET preamps may have more of a lush sound then the bipolar Krell stuff (which is typically more clean sounding).  All of it should be tight and crisp, but would give you a lot more warmth and body then the Emotiva XSP.   Tube may be good here too (also McIntosh), but the tube or mac stuff may be too slow if you like crisp sound.

Whatever you do, keep the Parasound.  I agree a tube pre-amp is a good way to go.  Have a look for example at Rogue Audio.  Also the Doge pre-amp (I nearly bought one).

One other thing to try of course is the treble control.  I would try turning it down a couple of notches.  This depends on how it's implemented though. They aren't all shaped the same.

Usually any impedance over 10k is considered high and acceptable by most preamps.  The more sensitive preamps will start to roll off high frequencies as the amplifier impedance drops or the volume control is changed.  Look at a couple of reviews at Stereophile. In the measurements you'll see this effect.

No modern solid state amplifier should care however, and many if not most can tolerate down to 600 Ohms.

The differential input impedances of amplifiers is a product of their design and what brings this on is beyond my scope of understanding. I do believe that this differential, in consideration alone, has little value in determining which amplifier is 'best' for a particular system.

What is of most importance is that the ratio of the amplifier input impedance be at least 10X (some say 20X) that of the output impedance of the driving preamplifier. What is the output impedance of the preamp? It is likely that it is low enough that the ratio would be met by all the aforementioned amplifiers.

I agree with those who suggest trying a tube preamplifier. Hope you enjoy the Rotel amplifier. 

Thank you for very good advised Erik. I just check out the in put impedance from 2 amp + 1 preamp below: Parasound a21: 33k unbalance , 66k balance (xrl) input impedance and input sensitivity 1 volt. Rotel RB1582 MK2 (just bought not try yet) input impedance : 12k unbalance 100k balance (xlr)and input sensitivity: 1.9 volt (Rca) 3.0 volt (xlr).my Emotiva xsp1 input impedance: 50k ohms.my question is how come all input impedance from 3 unit are all different? And are they effect to sound quality or performing?Which amp is matching with my Emotiva preamp?

Rotel and B&W do business together, but I don’t think they a particularly good match, any more than Krell is (yeah, that’s my opinion).

Given the usual tonal balance of the B&W nautilus line, I’d say you probably need genuine tone controls such as from a DiracLive or miniDSP type of solution. This being Audiogon no one wants to hear that, so let’s stick with the really expensive options.

Parasound amps are very neutral to a touch warm. I lived with a pair of the A23s and really liked them.

If I had to change the sound with changing equipment I would say change your preamp. The Parasound P5 should be skipped in favor of the P7 or JC2 if possible. Neither is a tube pre-amp but the P7 is neutral and open without actually being warm or cool with built in bass management. If that’s not warm enough, try out a modern Audio Research, Conrad Johnson (old or new) or any other tube pre.

I would experiment, but of course doing so in your system if at all possible is what I would try.

Again, back to solutions that are pretty expensive for the benefit, Wireworld speaker cables will also warm up the sound and help perceived imaging. Stick to the low to midrange cable for the warmest options. The good news is I think a place like the Cable Company will lend them to you.

Of course, something else that will affect the perceived tonal balance is room acoustic treatment. The more mid to high frequency damping you have, the more it will lower the perceived treble and warm up the sound, as well as improve imaging. GIK Acoustics is a great place for products and advice. 


Best,


Erik

I have a pair of 805's and love them.  I have a NAD receiver hooked to them and its pretty warm.  Its my HT system but does sound awesome.  

I may try looking for Mcintosh tube Pre-amp like c2200 see how it's work. If I try tube Pre-amp it must be Mac.I won't try the other brand tube Pre-amp because they look so ugly.I do like both warm sound and beautiful appearing like Mcintosh tube Pre-amp.It is just my though or my dream because Mac stuff is so expensive.

Thank You for all your help.I will try Rotel rb1582Mk2 and see how the sound going.I do loved my B&W 805 so much and I won't change it.If I do change it I will upgrade it to 805 D2 or D3.my rb1582mk2 will arrive next week and will let you guy know how it is work.Audiogon forum is very helpful and wonderful place to learn audio gear.Thanks again to all you guy for helping me.

have you considered buying different speakers?

not a B&W fan myself so I have a bias...

good luck

A21 is a very nice amp; not sure I'd ditch it for a Rotel. A tube preamp as mentioned above will probably do the trick and there's plenty to choose from so hopefully you have a local dealer that will let you drag one home first. Cables will make a big difference, especially a nice power cord on your amp. Lastly play with room treatments as your room might just be hot to begin with.

The A21 is a very nice amp with solid reputation. I’d look into a tube preamp that has the tonality you want. If you are willing to go used, a quick search shows these choices all under 1k. Be sure to check output impedance to ensure compatibility with the A21.