F5 needs a preamp for vinyl?

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Completed my F5 a few weeks ago. It sounds awesome. With CD's.

If I switch over to my vinyl rig it sounds like crap. My past experience has been opposite...my vinyl setup always sounds better than CD.

I am running nothing but a 25K pot in front of the F5. I tried a buffer after the pot but it did nothing good. Probably worse actually. I have 200ohm gain resistors in the F5 for a little more gain.

My vinyl setup has way less gain than my CD player. I can get enough volume out of it maxed out but it just seems to lack dynamics and soundstage. It is just lacking compared to CDs.

Again, with amps I've had in the past vinyl has always been better than CD. My vinyl rig is a Thorens TD145/Denon 110/Le Pacific (Boozehound) JFet phono amp.

I can only assume that I need more gain or output out of my vinyl setup to make it work well with the F5. I know a lot of people are runniong B1s in front of F5's but all signs are telling me this amp needs a preamp or a hot source to sound good.

Any ideas? I could do up a Jfet BOZ I guess. Or I could start buying CDs again.
 
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matter of perspective

if you're having gain/authority issues using your vinyl rig , comparing to CD rig ....... then your vinyl rig demands decent line stage after ....... not that F5 demands line stage

B1 is 0db gain , so - go figure ; if you have SPL but not authority , B1 is the cure

if you lack SPL , find some line stage with gain
 
Congrats on the F5. You definitely need a phono preamp to amplify the TT to same levels as CD players. With an F5 under your belt, consider a Pearl 2 as your next project, fantastic phono preamp. You could a cheap Pyle phono preamp for $15 for the interim until you finish.
 
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Boozehound needs a pre-pre

From Site: Boozhound Laboratories JFET RIAA Phono Preamp Kit

If you have a MC cartridge you will need a pre-preamp

Denon 110 is hi-output cart, but you will see it still needs a nice boost, and that's the whole point.
I have the DL-110, use 1k loading. Of course you should test for yourself the difference in sound between 47k and 1 k.

good luck!

Vince
 
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The Pearl 2, Mesmerize B1, and F5 make a fantastic combo. The Pearl has plenty of gain to drive the F5 to room-filling sound and then some.

+1, I am using Pearl 2 -> B1 -> F5tv2. No problem with gain levels. I get equal volume level for my Maranz CDP and Pearl 2 with HOMC cart, Denon DL-110. With LOMC cart DL-103 I need to raise volume beyond 12'o clock position.
 
As a test, I hooked up an old Carver C1 preamp I have lying around. The preamp line gain stage is fried but the MC section works. Using the tape out I can use it a a phono stage.

The additional gain of the MC stage vs. the Boozehound seems to be helping. I loaded it at 47K, I have tried different loading w/the Denon 110 but I always seem to end up at 47K. It's a little too late tonight (kids and wife are sleeping) for critical listening but so far so good.

So, I could get some extra gain in my phono stage or use a preamp instead of passive pre. Does it really matter at which point I add the gain? Any advantage to adding gain before the phono stage (example: step up transformer) or after phono stage(preamp)?

So, I really like my Boozehound phono stage, except not enough gain for the F5 w/passive pre. So he's selling these "pre-pre" MC gain Jfet gain stages:

Boozhound Laboratories: JFET Moving Coil Pre-Preamp lit

I am thinking about putting these in front of my Boozehound phono stage to get more gain. I track down a schematic (it's actually a bit different but almost the same)...looks pretty close the the jfet BOZ. In fact, other than some resistor and cap value changes it is the Jfet BOZ.

So should I go the hotter phono preamp option or Jfet BOZ? That's the question.

Regarding the B1, I can see it's value with some amps but I don't see the need for impedence matching w/the F5. I tried a tube buffer after the passive pre. No change in dynamics. In fact, may have been worse. I have using Tripath amps in the past that were sensitive to input impedence and the buffer helped tremendously. Not with the F5. I would rather not have the extra caps/etc. involved with a buffer in the signal if it's not serving a function.

I do think this is a input voltage/gain situation and not a SPL/volume situation. I have enough volume. It's the dynamics that are missing.
 

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I cobbled together a jfet boz. Vinyl sounds awesome. F5 needs a preamp i think. Everything is better. My expeience is that the f5is a bit handicapped without a preamp likes input gain. Some may disagree but i cant see how a buffered passive pre is the right combo for an f5. Thanks for the help guys.
 
It all depends on what's driving the preamp. The F5 needs some gain, but give it too much and you're going to be clipping it. It's only 25w per channel after all.

I'm listening right now with a 2.5mv cartridge into a Pearl 2 with about 60db of gain, into a DCB1 then the F5. That's right in the sweet spot between not enough and clipping, and the sound more than fills the room.:D:D
 
It all depends on what's driving the preamp. The F5 needs some gain, but give it too much and you're going to be clipping it. It's only 25w per channel after all.

I'm listening right now with a 2.5mv cartridge into a Pearl 2 with about 60db of gain, into a DCB1 then the F5. That's right in the sweet spot between not enough and clipping, and the sound more than fills the room.:D:D

True. But the 60db pearl is really meant to be used w/a LOMC cart. So you are getting your gain w/the high output cart (2.5v) and the relatively massive 60db of gain.

I was thinking about going that route too...I have a 1.6v output denon cart. But I figured my phostage was 40db plus the 20ish db of the jfet boz was pretty much the same thing. Actually, I probably have less overall gain than you, due to the lower output cart.

I haven't noticed any clipping yet. And it's about as loud as I can stand. And the dynamics are back. Agreed though, you want the amp to clip right at max output.
 
I am running Pearl 2 with F5, using Yamaha receiver Direct sound preamp outs with my Rega table. It crushes the CD and Sonos. Looking to replace the Yamaha with a Pumpkin/Shunty. Check Zen Mods signature.

Nice idea - I will need an interim Pre to run my F5 until I can build a Pearl2 / B1 combo. Forgot I could possibly use my Sony surround receiver for that. It has a phono stage also. Just trying to think through how this will work.... Any gotchas you can think of? My front speakers are decoupled from the receiver via a Niles DPS-1 amplifier selector, so I can have them wired to either the receiver or the F5 at the push of a button (at the moment I have a Sansui AU-101 as the alternative amplifier, to be replaced by the F5)

So this is what I am thinking:

  • Wire pre-outs from receiver to F5
  • Wire turntable into Receiver Phono inputs
  • Alter output for Phono to "pre out" in receiver OSD? This is the bit I can't get my head around...
  • Select Phono output on receiver
  • All audio should be sent to the pre-outs only?
  • Receiver correctly doesn't output sound to centre speaker (I have no surrounds / sub)
  • Select Niles DPS-1 to connect front speakers to F5

Expected Result: Record is being RIAA equalised and phono-pre-amplified by Receiver phono stage, with gain added by Receiver pre-amp. Sound is amplified by F5 and output to speakers.

Reckon this will work?
 
Nice idea - I will need an interim Pre to run my F5 until I can build a Pearl2 / B1 combo. Forgot I could possibly use my Sony surround receiver for that. It has a phono stage also. Just trying to think through how this will work.... Any gotchas you can think of? My front speakers are decoupled from the receiver via a Niles DPS-1 amplifier selector, so I can have them wired to either the receiver or the F5 at the push of a button (at the moment I have a Sansui AU-101 as the alternative amplifier, to be replaced by the F5)

So this is what I am thinking:

  • Wire pre-outs from receiver to F5
  • Wire turntable into Receiver Phono inputs
  • Alter output for Phono to "pre out" in receiver OSD? This is the bit I can't get my head around...
  • Select Phono output on receiver
  • All audio should be sent to the pre-outs only?
  • Receiver correctly doesn't output sound to centre speaker (I have no surrounds / sub)
  • Select Niles DPS-1 to connect front speakers to F5

Expected Result: Record is being RIAA equalised and phono-pre-amplified by Receiver phono stage, with gain added by Receiver pre-amp. Sound is amplified by F5 and output to speakers.

Reckon this will work?

That would work, The preamp out should send all the signal through the preamp amp. Think of it as disconnecting the preamp from the amp in the reciever. Usually there are preamp outs for each channel, use the one labelled "front".

You wont be able to use the receivers power amp section though. Theoretically you would be able to unplug the rca's from the preamp out, switch it back to "normal" on the osd, flip the switch on the speaker selector and use the receivers speaker outs again.

It might be just me but this setup would make me nervous. That Niles amp selector would make me worry. The f5 won't like shorted outputs, has no dc protection and in general has no safety mechanisms like some of the new consumer stuff. Mess up and your Sony receiver will go into "protect" mode. Mess up with an F5 and your speaker cones might exit the building.

I'd make sure all amps are off before doing any speaker switching.

Also, snotty audiophiles like me would poo-poo that speaker selector. It's likely current limiting/bottleneck.

Last question: Why can't you just set the reciever to 2 channel mode? That should kill output to the center and you won't need to use that speaker selector. Just hook up "front" preout to the f5. That's it. Assuming you have pre outs for each channel.

Also, you could run the turntable into the sansui's phono stage, use the tape out (makes it into a phono stage) and put a pot before the F5. That's the poor man's Pearl/B1.
 
True. But the 60db pearl is really meant to be used w/a LOMC cart. So you are getting your gain w/the high output cart (2.5v) and the relatively massive 60db of gain.

I was thinking about going that route too...I have a 1.6v output denon cart. But I figured my phostage was 40db plus the 20ish db of the jfet boz was pretty much the same thing. Actually, I probably have less overall gain than you, due to the lower output cart.

I haven't noticed any clipping yet. And it's about as loud as I can stand. And the dynamics are back. Agreed though, you want the amp to clip right at max output.


Good thought. ;)
Just keep in mind it's mV, not V. :D
Most HOMC carts should be more close to 1 mV than 2.5 V.
 
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