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Update on RF-5 to RF-7 Upgrade:


Doug C

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As posted earlier I had the RF-5's for about 6-months and upgraded to the RF-7's about a month ago. After extended listening I found the RF-7's to be just a tad grainy on the top compared to the RF-5's. Other than the added sensitivity provided by the RF-7 I was actually thinking that I had a slight preferance for the sound of the RF-5 (very slight preference).

Had been using my Marantz CD-17 CD player with both speakers and always considered this unit pretty good. For the heck of it I ordered a Bel Canto, DAC-2 outboard DAC from audioadvisor with 30 day return policy. The DAC-2 also upsamples to 24 bit 192kh before the analog conversion.

Based on the price of the DAC-2 ($1,300.00) I really had no intention of keeping this piece. Have to say however that after a week of listening it will be hard to return this little guy. Now the change is not dramatic or night and day. But that little bit of high end grain that I hear from the RF-7's (compared to the RF-5's) is gone with the DAC-2 with even more detail on the high end. This has led me to conclude that the RF-7's high frequency driver is capable of more detail compared to the RF-5. I believe now that the added grain I heard from the RF-7 was actually a weakness of my source and not the speaker.

The DAC-2 has also opened the soundstage further with more space and air. The most noticable improvement is in the low bass. Bass notes are better defined and more distinct with a very natural decay.

There has been another side effect that does not make much sense to me. Previously when routing the analog signal through my B&K preamp using direct pass-through there was a slight loss of detail as opposed to going direct from my CD player to the amp. With the DAC-2 I really can't distinguish any difference between the two hook-up methods. This may be due to different interconnects? I had been using 2 sets of 1 meter Homgrown Audio silver interconnnects. When I purchased the DAC-2 I also purchased two pair of .5 meter Silver Reference interconnects from Decware. Apart from the sound these interconnects are reasonably priced, thin so they don't take up much space on the back of my already congested preamp, very flexible and easy to work with.

With the DAC-2 in the mix there is no longer any doubt, I prefer the RF-7's over the 5's. The 5's are still great speakers. Since I'm using a 2 watt/channel tube amp the added speaker sensitivity is a big plus. The added volume output capability is significant (more than I was expecting).

Doug C

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Good point, No I have not tried the new interconnects with the DAC out of the system and will do that.

I did compare my DVD player connected via digital coax to the DAC versus my CD player connected via digital coax to the DAC and could tell no difference. Since my equipment rack is already crowded I've been listening the last few days using my DVD player as a transport. I've also tried optical to the DAC and hear no difference compared to the coax. The DAC-2 has coax and optical inputs with a push-button selection switch. I compared the two by switching on the fly using the selection switch.

I now have the DVD player connected via digital coax to the outboard DAC and DVD players optical output connected to my B&K Reference 30 preamp. I'm able to switch via the preamp between the analog out of the outboard DAC and the analog out of the B&K's onboard DAC. I have balanced the levels from both to within 0.5 dB. The sound qualities described in my original post are evident (the Bel Canto DAC-2 being better). With the outboard DAC there is an extra set of 0.5 meter interconnects (between DAC and preamp)compared to using the B&K onboard DAC where the only interconnects in the path are from the preamp output to the amp input.

I've always been a bit skeptical about interconnects having a significant impact on sound quality? Good quality connectors are a must but can't say I've ever really been able to attribute any sonic differences between different interconnects of good quality? But I will make a point to go back to the Homegrown Silver interconnects for a fair comparison.

Doug C

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Send back the DAC.

Leo and myself are in the process of rebuilding the crossover boards of our RF-7's.

Leo is going the route of Jensen PIO's for the series caps in the tweeter circuit. I, OTOH, after much trepidation and loud wailing -- I have decided to go with ICW's and Auricaps (yes, I can hear the moans from the forum gallery).

Leo is using the Wellborne Moondogs, and I am using the Wellborne Apollos. I'm using an active preamp, and Leo is using a passive. We also have somewhat different musical tastes. These things, as well as the insane prices of the PIO's (with no guarantee of overwhelming success) -- has led me into a different direction.

Before plopping down $1300, you might want to wait and see what Leo and myself report back as far as how the RF-7 responds to the crossover changes with out SET amps. $350 in crossover upgrades may take you further than that DAC.

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I would bet the problem with your RF-7s is just there extra efficiency bringing out the worst in your system. I bet the RF-5 just couldn't reproduce the harshness of the top end of your gear. This is why the upgraded Dac helped limit the harshness. The more efficient your speakers are the more your sources become a problem.

Craig

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I'm a babbling idiot. You and Craig have surmised correct, and the additional sensitivity of the RF-7 is surely the reason for this.

I was just thinking there will be several new topics in the near future regarding SET and modded RF-7's, and that other users of SET might want to hang on before spending a small fortune on component upgrades. There will surely be lower distortion levels, as well as a slight voicing change that might influence the way downward components are perceived.

Of course, I'm assuming the changes will be positive, and that RF-7 users will be begging Leo and myself to rebuild their boards for them. Of course, then there would be RF-3's, RF-3 II's, RB-5's, RB-5 II's, RC-7's, RF-35's, RF-75's, etc...

...and at that point, Leo and myself would have to pay Kelly to build us a webpage, which would result in us spending our remaining days happily sucking solder fumes.9.gif

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The RF-7 is real detailed in the highs. Any source or amp problems up there are real obvious. But, when it's right, it's very realistic. I'm struggling with CDs myself. I found myself doing most of my Moondog checks using records because I just don't trust the sound of CDs. Maybe a super DAC would help.

leok

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CD's isn't that the truth I was listening to a FM classic rock station today and foreigner came on and I thought man I haven't listened to that CD in years. Okay I know but I grew up with it !! But anyways I popped the CD in and turned it up and wow I thought my system went to sh!t !! Good old 80's CD's !!!

Craig

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I have very few CD's from the 80's I can even listen too. As a general rule, I dont' buy anything on CD from that era unless it has been remastered with 22 bit or higher, and remixed.

Now, newer recordings are something completely different. I have yet to hear anything in the last 10 years that doesn't sound at least as good as the vinyl I listened to in the 70's and early 80's -- and some stuff, goes WAY beyond.

I think we just need to voice our systems based on what we typically listen to as far as source and material goes.

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Now, newer recordings are something completely different. I have yet to hear anything in the last 10 years that doesn't sound at least as good as the vinyl I listened to in the 70's and early 80's -- and some stuff, goes WAY beyond.

Dean

Correct me if I'm wrong , But I think your statement suggests that to you, current made cd's sound as good as vinyl?

Tom

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Hmmm, well, it would be tough to make a blanket statement like that, as I've never heard a $1K table with a $1K MC (Dynvector) -- but GENERALLY speaking, yes, I think newer CD's sound as good as most vinyl if not better. In reality however, pick your poison, because both have problems. Again, largely a matter of taste. I prefer the additional slam and speed of digital.

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I have heard some newer bands recordings on vinyl and I think that as far as slam and speed goes they don't really give up anything to the CD crowd.

Two albums I have been listening to lately are Less than Jake "goodbye blue and white" and Blonde Redhead "Melody of certain damaged lemons".

The blonde redhead album is on the electronica side of things and I think exibits some very "precise" attack and detail.

I also can't get over how good cymbals sound on vinyl, they are(imho)so much more defined then on CD.

Oh well, just some thoughts of mine.

Peace, Josh

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Dean,

Fair enough, I agree in regards to the slam & speed issue, but unfortunatley at the expense of it sounding digital. I perfer the smooth, warm & true presence sound of vinyl. Regarding your statement of having to spend 2 grand to obtain quality vinyl sound, not. It can be had for a fraction of that used of course. With all due respest I'm not questioning your preference, I just feel vinyl defenitly outclasses cd's in more ways than one, and it's truley addictive if the correct sources are in place. Just my personal opinion.

Thankx

Tom

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Dean, you have a long way to go in the understanding of dynamic range with vinyl vs Digital. Remember the learning curve with tubes vs solid state? Now add in PP tubes vs SET. Soon, it will be vinyl vs digital... although I hesitate recommending this to those that don't have a record collection. Dementia and gnashing of teeth with commence. Believing in the Lord will not help, either.

Suffice to say, good vinyl reproduction actually has more uncompressed dynamics and perceived dynamic range that good digital. Once again, in many ways, it mirrors tube vs solid state sonics.

Of course, mediocre vinyl playback can be a real downer. But quality vinyl playback makes digital look like a connect-O-dot drawing in many ways. That is obviously an exaggeration but made to drive the digital bits home.

kh

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"...good vinyl reproduction actually has more uncompressed dynamics and perceived dynamic range that good digital."

Lot's to learn for sure, but this one is tough. Vinyl has compression applied in the recording process, AND playback. Even the medium itself has limitations in this area.

Of course, I have never heard a very high quality vinyl playback system -- so I am a bit out of my realm here. As a matter of fact, I think I'll just stop talking now.

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