Pre/Power Amp Issues

[JohnNB]

I've have an old Rotel RA-01 integrated amp brought back to life and noticed it had a pre-amp out facility so I coupled it to my Roksan K2 integrated, using this as the power amp. I'm really pleased with the results. The sound quality seemed to move up a gear or two - louder, more responsive, more clarity and generally more umph. I have been discouraged from going down the pre/power route in the past by my local dealer, but I'm so impressed with the improvement I would like to understand what's actually happening sound wise. Am I listening to the Roksan power section only, with the Rotel providing the input and controls etc, or is the sound produced by a combination of the two amps? It would appear to be the later. The Roksan delivers 120w a channel, so more than adequately drives my speakers, but together they push the power way beyond my speakers capabilities. I therefore seem to be driving them with more control to good effect.

I can't imagine going back to an integrated amp now and I'm looking ahead to replacing the Rotel with a more modern and versatile pre-amp, i.e. one with digital inputs. Advice and guidance on whether people think I'm going in the right direction and are there any potential pitfalls I should be aware of, for instance, have I got lucky with my pairing and would some combinations not work so well. Eager for your thoughts.

[struth]

Hey if it's sounding great why change. I you might not get the same synergy again. I at a guess the pre output may well be higher than the rocsans own pre

[Light Dependant Resistor]

Hi John
Similarly I am a firm believer in the separate pre /power amp approach. Like you I tried a old Rotel RA611 by stripping almost everything out of it
other than its transformer - I then built it up as a dedicated preamp. It was far better than other combinations... but that was over 12 years ago.

Since then I have dedicated most of my time to attenuation as a serious subject using Light Dependent Resistors. Marco has one of these builds,
awaiting a review.

If you can suggest you try a passive preamp - the reasons are that there is much higher chance of your source component providing what it can
rather than its Left and Right signal enroute to your power amp being changed by other electronics disguised as a preamp.

Ldr's present a exciting form of passive as they remove the mechanical wiping or switching of audio signals seen with switched attenuators
and potentiometer based passive volume controls.

[ReggieB]

For me, the pre/power vs integrated is all about budget. That is a good integrated is better than a poor pre/power and on a tight budget it is easier to find a good integrated than a pre/power combo that would better it.

Of course the next question is what constitutes a tight budget. Personally, if buying new, I'd suggest less the £1000 as a finger in the air estimate. That is, if you have an £800 budget and want to buy new, you're likely to find what you want by going the integrated route. With some of the latest American kit (Schiit and Emotiva for example) that ceiling drops a little.

Second hand things get a little more interesting. I'd suggest it's roughly around £400.

Of course there are exceptions (very good expensive integrated, and some second hand bargains if you're willing to search at the opposite end). Also if you hunt around a passive pre-amp can be picked up remarkably cheaply, but they don't suit everyone - or every power amp/sources. It really all depends how much effort you put into it.

Another factor is whether you want to go down the valve route. Valve power amps bump the ceiling up significantly.

And the opposite is that if you have a large budget, it's easier to find a good pre/power combo. Ultimately, pre/power is better - mainly I believe because they don't share the same power supply.

Lastly pre-power can add more flexibility - more inputs, a variety of inputs that match your sources (digitial, line level, and phono).

[JohnNB]

Thanks Guys. As usual, the 'can of worms' is bigger and more wriggly than I expected, which leads me to agree to some extent with Grant in that I love the sound I'm now getting - and I'm getting it on the cheap as the cleaned-up Rotel is about 20 years old and cost £250ish back then. But hi-fi perfection is a merciless and ever restless mistress!! Also, I would like to add digital inputs to a pre-amp as my 8 year old Arcam rDac has recently packed up and Arcam are suggesting it's not worth fixing. So I've lost the ability to play my cd player and dab tuner through an external dac. They sound ok directly fed into the Rotel, but better through the rDac - and it would free up the RCA inputs of which I'm currently using all 5.

In response to Rob; I'm happier using the Roksan as a power amp rather than as an integrated. I found the volume control tricky and unresponsive til it got to about 12.30 on the dial, but in power mode it's the beast I wanted it to be! I'm thinking a £300 or £400 hundred region spend on a new or second hand pre if I could find one with a minimum of 5 RCA inputs, 1 Co-axial and 1 Optical. Since reading your replies I've had a quick look online and found prices from 20 to 3,500 quid! Then, reading Chris's response, the LDR issue is yet another temptation. The technical stuff is way beyond me Chris, and I therefore discount anything involving DIY. None of the for-sale pre-amps I looked at had digital inputs, or mentioned LDRs, so any suggestions of LDR pre-amps with RCA and digital inputs around that price range?
Thanks again.
John

[Stryder5]

Thanks Guys. As usual, the 'can of worms' is bigger and more wriggly than I expected, which leads me to agree to some extent with Grant in that I love the sound I'm now getting - and I'm getting it on the cheap as the cleaned-up Rotel is about 20 years old and cost £250ish back then. But hi-fi perfection is a merciless and ever restless mistress!! Also, I would like to add digital inputs to a pre-amp as my 8 year old Arcam rDac has recently packed up and Arcam are suggesting it's not worth fixing. So I've lost the ability to play my cd player and dab tuner through an external dac. They sound ok directly fed into the Rotel, but better through the rDac - and it would free up the RCA inputs of which I'm currently using all 5.

In response to Rob; I'm happier using the Roksan as a power amp rather than as an integrated. I found the volume control tricky and unresponsive til it got to about 12.30 on the dial, but in power mode it's the beast I wanted it to be! I'm thinking a £300 or £400 hundred region spend on a new or second hand pre if I could find one with a minimum of 5 RCA inputs, 1 Co-axial and 1 Optical. Since reading your replies I've had a quick look online and found prices from 20 to 3,500 quid! Then, reading Chris's response, the LDR issue is yet another temptation. The technical stuff is way beyond me Chris, and I therefore discount anything involving DIY. None of the for-sale pre-amps I looked at had digital inputs, or mentioned LDRs, so any suggestions of LDR pre-amps with RCA and digital inputs around that price range?
Thanks again.
John

If you are running the pre out of the Rotel into a line input on the Roksan you using both pre amps to feed the power amp section of the Roksan.

This is not a pre amp/power amp situation.

You are using the gain and characteristics of the Rotel feeding into the gain and characteristics of the Roksan, hence your increase in volume.

Gary

[JohnNB]

Thanks Gary. I'm not running the Rotel through a line input on the Roksan. I spoke to someone at Roksan before I linked it to the Rotel and they advised that I can use the K2 as a power amo by connecting it to the bypass input on the K2, thereby bypassing the pre-amp function of the Roksan.

[Jazid]

New cheap DACs have come on in leaps and bounds, a fine converter can be had for £100 or so.

Re. Preamps my advice is the same as Struth's: if it ain't broke don't fix it. I know that temptation to buy very well, but also know that three or four hundred quid can be spent easily without any obvious upgrade, and the risk is all the greater since you have lucked out on the synergy front already.

For the money you could add/upgrade a streamer or NAS, or buy a new DAC and keep the change?

Sent from my BLA-L09 using Tapatalk

[Stryder5]

Thanks Gary. I'm not running the Rotel through a line input on the Roksan. I spoke to someone at Roksan before I linked it to the Rotel and they advised that I can use the K2 as a power amo by connecting it to the bypass input on the K2, thereby bypassing the pre-amp function of the Roksan.

Cool, always happy to be wrong :)

Gary

[ReggieB]

Yes, I agree with James, I'd spend the money on a DAC.

[JohnNB]

Thanks to all your words of wisdom I've decided against changing the Rotel improvised preamp and going for a new dac. I've looked at the Beresford Caimen and the Cambridge DACMADIC 100 and the MAGIC 100 Plus. The later uses upsampling, which I'm suspicious of, and the other Cambridge only plays up to 96kHz files, so I'm leaning towards the Beresford. Anyone got experience of any of these dacs?

John

[Macca]

Some DACs incorporate a pre-amp too so you could kill two birds with one stone.

[mikmas]

Thanks to all your words of wisdom I've decided against changing the Rotel improvised preamp and going for a new dac. I've looked at the Beresford Caimen and the Cambridge DACMADIC 100 and the MAGIC 100 Plus. The later uses upsampling, which I'm suspicious of, and the other Cambridge only plays up to 96kHz files, so I'm leaning towards the Beresford. Anyone got experience of any of these dacs?

John

Just making a left field suggestion but you might want to consider a Quad Vena as well ... it has a range of digital in/outs, 2 x analogue in, Bluetooth and can be used as a pre-amp or, on its own, as an integrated. I have one and the performance on all fronts is excellent. I have used it as a preamp with a Quad 405-2 .... phenomenal.

Quad have just brought out a new 'beefed-up' version with added Phone Stage so the original model is likely to be available 2nd hand fairly easily and at a reasonable price. One was sold on AoS just recently for £350, which will be about the going rate I would think.

https://images-na.ssl-images-amazon.com/images/I/61XBQxH8TUL._SX679_.jpg

[JohnNB]

I'll look out for a 2nd hand Vena Mike. Good suggestion