Anybody Not Using A Preamp?

[Cathedral Guitar 9]

I'm setting up a my 3-CH system using monoblocks to power my 3x La Scalas, and running them directly from a pro audio Metric Halo ULN8 DAC firewire interface. Anybody else running power amps w/o using a dedicated preamp?

[Edgar 1015]

I'm using one of these in a mostly-digital system: https://www.steinberg.net/en/products/audio_interfaces/ur_series/models/ur824.html.

[tube fanatic 1162]

If the input sensitivity of the amps allows the source to drive them to the needed output power all is well.  An ideal system has as little electronics in the signal path as possible.  Of course you would need to control the output voltage of the source for volume control.
 

Maynard

[Coytee 3338]

I was once doodling behind the rack with the rats nest of wires....

 

When I was done, I popped a CD in and was immediately impressed with the improvement of sound.  It was as easily discernable as night is from day.  I was floored....and went to turn the volume up to tap my toes a bit more....and nothing happened.

 

Long story short, the (solid state) amp had an input sensitivity of 1V and I had grabbed the wrong set of wires and had inadvertently wired my CD player directly into the amp instead of the preamp.  (oops)

 

It gave me a very quick and harsh lesson on how the electronics can influence the sound.....however, I needed the preamp for selection AND drive to higher volumes at times so bypassing it didn't work from a practical point of view (not to mention I later sold that amp....  a dbx BX-1)

 

Sounded great while I was directly hooked up.

[babadono 6616]

i use this

[Dave A 2363]

I run directly from my PC to my Crown XLI800 if I am feeding a set with passive crossovers. If I am feeding my main system it goes from my PC to the Xilica to two XLI800 amps  and to the bi-amped two way speakers. It sounds fine to me and I am a minimalist when it comes to feeding my speakers.

[SWL 1906]

i use this

Now we're talkin.....but is that all you got?

Sent from my SM-G950U using Tapatalk

[Schu 4939]

a simple attenuator is good...  either resistor ladder or like

[Panelhead 160]

 I have many preamps in the attic. Tube, solid state, and passive.  None in my listening room. A preamp and associated cables only degrade playback.

  Using pro interfaces that have four channel monitor output to drive main speakers and subs. Not many options out there for four channels with one volume control.. 

  Like Edgar mentioned, Lyngdorf has been selling these since the mid 2000’s. I first heard one at RMAF around 2007 or 2008. Bought one in 2009. Still have a couple. 

  Just hooked back up one one of the Focusrite Clarett 4Pre interfaces this week. Drives the amps and subs directly. Software based 64 bit crossover to set the filters.

[Shakeydeal 1098]

Resistor based passives are inferior to a transformer/autoformer type or an LDR. If your system is passive friendly, these devices can kick some high $$ preamps to the curb.

 

Think Tortuga, Sonic Euphoria, or anything with a Stevens & Billington transformer.

 

Shakey

[DALEDEEE 20]

I run streamer to DAC to crossover then to the amps.  Never had any problems and lots of volume.  Found this out when I needed to replace both my CD player and my preamp.  So in an effort to keep costs down, I tried this and it works great.   Streaming is all I do.

[Shakeydeal 1098]

8 minutes ago, DALEDEEE said:

I run streamer to DAC to crossover then to the amps.  Never had any problems and lots of volume.  Found this out when I needed to replace both my CD player and my preamp.  So in an effort to keep costs down, I tried this and it works great.   Streaming is all I do.

 

It's not just about having enough volume. Some DACs don't have a robust enough output stage to properly drive an amp. You end up with lifeless sound. And you might not recognize it for what it is until you insert a good active preamp.

 

If a system is passive friendly, low source output impedance coupled with high amp input impedance and sufficient input sensitivity, an active preamp might not be necessary. But remember that the attenuator used on any preamp, active or passive, is the heart of that device.

 

Shakey

[Edgar 1015]

9 hours ago, Panelhead said:

 Not many options out there for four channels with one volume control.

 

The Steinberg UR824 master volume control is digital (or so I'm told). A digital volume control is fine as long as its output is properly dithered. I don't know whether Steinberg dithers properly, or at all, so I do it myself in software. I'm using the UR824 to implement crossovers and lots of other signal processing anyway, so adding some dither is just another minor task.

[DizRotus 9138]

I do not use a preamp.  A balanced signal is fed directly from a Pono player to my DIY Texas Instruments TPA3255EVM based class-D chip amp, as well as a pair of iNuke1000dsp amps that each power a pair of DIY tapped horn subs.

 

The setup enables the track and volumes to be controlled from the Pono player.  It does not permit balance or tone control adjustments.  Overall, the compromises are worth it to me.

 

[Bubo 348]

I ran a CD player directly into a Yamaha MX-600 amp sounded great, the amp had gain control

Same CD player into a Yamaha DSP A-700 early Surround amp, which has a volume attenuater built in, sounded great.

Any amp that has pre amp in can be fed directly from your DAC, CD player or other.

There is also the direct button on lots of gear that bypasses all the pre amp tone and eq controls, sounds clearer.

On surround amps that have the direct feature, check the block diagram, decoding in the amps DAC then on the bus to the amp section sounds quite good

[DALEDEEE 20]

13 hours ago, Shakeydeal said:

 

It's not just about having enough volume. Some DACs don't have a robust enough output stage to properly drive an amp. You end up with lifeless sound. And you might not recognize it for what it is until you insert a good active preamp.

 

If a system is passive friendly, low source output impedance coupled with high amp input impedance and sufficient input sensitivity, an active preamp might not be necessary. But remember that the attenuator used on any preamp, active or passive, is the heart of that device.

 

Shakey

Thanks for the point.  The DAC has 2V RCA output and Pass amp has 47Kohm input impedance.  Is that good enough?

 

 

[Cathedral Guitar 9]

Here is a related question: a lot of simpler designs for tube integrated amps have just 1x volume pot, and 3-way selector switch. These generally have 2 input tubes, a rectifier tube, and the output tubes. On the other hand, many tube monoblocks also have the 2 input tubes, rectifier tube + output tubes -- but without a volume pot, and w/o the selector switch. So disregarding the multiple chassis / PSU of monoblocks, but is the only difference between an 'Integrated Amp' and 'Power Amp' the addition of a volume pot and a selector switch? 

[tube fanatic 1162]

1 hour ago, Cathedral Guitar said:

Here is a related question: a lot of simpler designs for tube integrated amps have just 1x volume pot, and 3-way selector switch. These generally have 2 input tubes, a rectifier tube, and the output tubes. On the other hand, many tube monoblocks also have the 2 input tubes, rectifier tube + output tubes -- but without a volume pot, and w/o the selector switch. So disregarding the multiple chassis / PSU of monoblocks, but is the only difference between an 'Integrated Amp' and 'Power Amp' the addition of a volume pot and a selector switch? 

In some cases only.  Integrated amps are designed for fairly low level sources while some power amps require much higher drive voltages.  The answer has to be considered for a particular unit in question.

 

Maynard

[juniper 203]

I dont use one, try to keep it as simple as possible. I use my CD player as one.....