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rupertn
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Preamps

Hi

I'm in the process of upgrading to entry level high end.

I have appleTV running into a DAC, connected to a tube power amp.

Neither have manual volume control, nor does the appleTV remote, and I do not have access to the iPhone remote control app.

As I understand it, a preamp connected between the DAC and power amp will give me volume control.

But, I also want to connect my turntable, must I specifically use a phono preamp, or, at the budget end of the spectrum, will any quality preamp do a reasonable job? Thereby killing two birds with one stone; manual volume for all music, and, vinyl capability. 

Or, if I just install a phono preamp, when I'm listening to iTunes, will the phono preamp diminish the signal from the DAC, meaning I need two preamps, and switch between one for digital and one for vinyl?

 

Any help appreciated!

Thanks

R

JoeE SP9
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Preamp

I suggest a preamp with a built in phono preamp.

jackfish
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A phono preamp boosts the weak signal

produced by phono cartridges and adds RIAA equalization.  The regular line level inputs (CD,TUNER,AUX,TAPE,etc.) of a preamp or control amp will not accommodate that weak signal. Hence, a phono stage is necessary to use a turntable.  So, a preamp, receiver or integrated amp with a phono input has a phono stage.  If there is no phono input a separate phono preamp will have to be used between the turntable and a line level input. You will not need "two preamps" for digital and analog.  The DAC will convert to analog the digital signal from the AppleTV which can then be fed into a line level input.  Is that clear as mud? cheeky

rupertn
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H, thanks for

H, thanks for advice.

 

Yes, completely understand why preamp is needed for phono, and, yes, the DAC is connected to the line level input (by this I assume you mean the tube power amp).

 

But, I need something somewhere that will give me output (volume) control.

 

The only thing I can think of is either

 

a) a preamp between DAC and power amp

b) a new power amp with outout (volume) control.

c) buy an iTouch for the remote control app, but then that'll only work with iTunes and I've jailbroken the appleTV with Firecore software so I can use whatever media player I want.

jackfish
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Yes, you could use a preamp between the DAC and

the power amp.  It sounds like this would be your best solution considering your turntable is in the mix. So you also should consider a preamp with a phono input. Line level inputs are on a preamp, receiver or integrated amp and allow the use of sources like a CD player, tuner or tape deck. The preamp, receiver or integrated amp will have switches to select each source and a volume control.  Some will have treble and bass controls or a tape/processor loop.  What is your price range for this solution and what sources besides the AppleTV/DAC and turntable will you use?  What kind of tube power amp and loudspeakers do you have?

rupertn
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I have a AMC CVT 2100as power

I have a AMC CVT 2100as power amp, 80W into 4/8ohms (input sensitivity for 1W/80W into 8 ohms 138mV/1230mV - I've no idea what that signifies)

Speakers I'm in the market for, I just bought some Kimber Hero interconnects and Kimber 8VS speaker cable, so I need to find some speakers with relatively high sensitivity (I think?), to pair with my amp. Going to look at Quad and take it from there. 

Just turnatable and appleTV as source, althought the iDAC does have an iPod port too. 

A friend told me not to buy a preamp with phono built in, but get a seperate phono preamp and something like the Jolida9A for everything else, which is around $500....I don't know...that's a very expensive volume control. 

My budget is running out, I'm leaning towards buying some good used speakers for $1k-$1.25k and trying to figure out an acceptable preamp workaround, if I could find a tube preamp with phono built in and aux inputs I'd certainly carefully consider it, but, there don't seem to be (m)any out there.

 

Thanks! 

commsysman
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Preamp Voltage Levels and Phono Equalization

First, you need to understand that "line-level" outputs, from CD players, tape decks, tuners, and most other equipment are on the order of 200 millivolts to 1 volt.

A phono preamp does TWO jobs;First, it amplifies and brings the output of the phono cartridge, which is only a few millivolts or less, up to line level. A moving-coil cartridge needs more amplification than a moving-magnet cartridge.

Second, and equally important, it equalizes the signal recorded on the vinyl. The signal recorded on the vinyl is actually "rolled-off" before feeding the signal to the master cutting lathe as the frequency goes lower and lower, because otherwise the physical size of the low-frequency grooves would take up an unacceptable amount of space on the record (a 12-inch LP would only hold about 5 minutes per side, if that). Thus the phono preamp must boost the low freqencies back to normal, and this requires a very accurate low-distortion filter to reverse the effect of the opposite-slope  filter that was used to make the record master.

Without equalization filters in the phono preamp stage, the treble would be un-naturally emphasized and the bass volume level would be very very low, because that is how it physically exists on the record. The phono preamp amplifies the low frequencies much much more than the high frequencies in order to restore the normal balance of the recording.

                   ***********************************************

AS for EQUIPMENT; for $100, you can buy the Musical Fidelity VLPS phono stage/preamp, which is excellent; nothing else will touch it for 3 times the price, in my opinion. I have an Audio Research PH-5 phono preamp, which cost $2000, in one of my systems, and the VLPS in the other, and there is only a slight difference in the sound quality (although the PH-5 certainly has many more features).

For a low-cost PREAMP, you can buy the Parasound ZPRE 2, which is $400 and has 4 audio inputs, an RS-232 input, and switching for 4 video inputs. Details available for the above on the Audio Advisor website. These two units should do everything you want for $500 total, and give you a lot of flexibility for future configurations. To get a preamp with a decent phono stage built-in, plan on spending $2000 to $8000.

For speakers; you can't go wrong if you buy the PSB Image T6 speakers for $1300 per pair NEW! I have had them for a year now, and they really are excellent.

Read the review from Stereophile on the T6, and then read the one in The Absolute Sound. They both basically said that it is an incredible speaker, especially for that price. The T5 is nearly as good for $1000, and the Monitor Audio M6 towers are very good for $700/pair. I could live with any of those speakers; good stuff.

P.S.- The amplifier spec means you need a 1230 millivolt input signal to put out 80W of power to the specified load (speaker) impedance. Lower input signal levels will produce less power output, obviously. That amplifier should drive 95% of the speakers on the market; any speaker with an efficiency of 87 db/w/m or higher should be fine, which includes the ones I recommended above.

rupertn
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Thanks, greatly appreciated

Thanks, greatly appreciated info. 

One follow up question, I'm not sure about mixing the Parasound integrated preamp with a tube power amp, will research this but if you have any comments, again appreciated.

 

Thanks

jackfish
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Another possibility is

 the Emotiva USP-1 preamplifier which is in the Holiday Sale right now for $370 delivered.  It has a very good phono stage, 30-day in home trial and a 5 year warranty.

http://www.hometheaterhifi.com/preamplifiers/689-emotiva-usp-1-stereo-preamplifier.html

http://www.tonepublications.com/review/the-emotiva-usp-1-preamplifier-and-upa-1-amplifiers/

There should be no problem mixing a quality solid state preamp with a tube power amp.

commsysman
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SOLID-STATE /TUBE PREAMP

Actually, the tube amp you have would sound great with a good tube preamp. The trouble is, I don't know of a good one for under $3000 or so.

I have never heard the Emotiva USP-1 preamp, but it sure looks like a tremendous value for $369, and it does have a phono stage. I don't know of anything comparable for much under $1000.

That is an incredible price for a preamp with all of those features; I would sure try it out if I were in your shoes. If the phono stage doesn't turn out to be quite what you want, there is always the V-LPS for $100.

commsysman
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JoeE SP9
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Spam

I beiieve they call it spam!

commsysman
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AUDIO RESEARCH PREAMP

An Audio Research preamp would be a wonderful way to go.

I am currently using the AR LS-26, which is now discontinued; the LS-27 is the new model, and is essentially the same. They are $7000 now, however.

My previous one was the LS-2B, which is also excellent, and I see one for sale on Audiogon for under $1000. That is something you might consider. I usually would not recommend buying used, but AR gear is so reliable and rugged that it is safe to buy used.

 

 

 

 

[quote=rupertn]

Hi

I'm in the process of upgrading to entry level high end.

I have appleTV running into a DAC, connected to a tube power amp.

jgossman
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Lazarus

I have for years now used a Lazarus Preamp.  They aren't very expensive, but they are rare.  They have a fantastic phono stage and the line stage is about as good as it gets, albeit a little laid back.  If you use one, it will seem a little warm if you are used to many SS amplifiers/preamps, but go listen to a live show, and you will likely find it to be about neutral and most of all NATURAL and non-fatiguing.  To boot, they are easy to work on which is good, because if you find one for under 500.00, it will probably mean it's ready to be recapped.  Also uses about the most common tube around, the 12AX7.

Good luck.

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