Newbie to tubes - need general advice on pre-amps

[ktm_2000]

Hi All,

I am looking for a pre-amp and would like to expand my horizons into the tube arena.

A bit of the problem I am trying to solve. I've enjoyed audio for years starting in college where I purchased B&W DM620s and a Yamaha amp. I still have the B&Ws and they are the mains in a home theater setup but have gone through a few generations of yamaha surround sound amps and primarily use my stereo for surround sound.

Lately I've gotten on a kick of going to thrift shops as a source to get items to feed one of my other hobbies and have come across a few finds. Here's the my thrift store finds and what I would base the the setup on

KEH Reference series model 1402 - ugly cases, but still sound good, one of the woofers needs to be re-foamed - stupid lucky found them for $30
Acoustic Research LS78 - thought I got a screaming deal for $15 - took it home and tested them and the foam on the woofers disintegrated - would probably stick with the KEH speakers.
Lexicon 412 Amp - Again stupid lucky, found it for $25 - fuses were blown and didn't power up, seems to work great after new fuses.

I've had the KEH/AR speakers for over a year now swapping them out with my B&W on my home theater, my recent find is the amp, I've temporarily setup my yamaha as a pre-amp and run the lexicon amp and have been blown away with its performance.

I would like to have a 2nd pure listening setup - plain 2 channel stereo, listen to cds, potentially add a DAC and turntable

I realize I need to spend a bit more on the pre-amp to get something quality but don't want to spend much more than 1k and looking for recommendations on the lower end of tube pre-amps.

Am I better off looking for an old tube setup or something new like the schiit freya, or is building one's own from a kit a reasonable way to go without breaking the bank?

I when it comes to tubes, I am a complete novice and assume I don't know anything

Suggestions to start looking? recommendations?

Thanks in advance

 

[Erhard-Audio]

first, welcome to the never ending story of tube audio gear!
There certainly are endless choices out there, and it can be a bit overwhelming for the newbie. In any case, I have sent you a 'pm'.
There are a lot of good members here, so get ready for an onslaught of kind!

 

[kappclark]

Good luck in your quest -- lots of good gear out there ...

the only separate tube preamp I have owned i the simple FX-Audio Tube-03.with the GE tubes. just wanted to see what it sounded like with a decent Parasound power amp --- a pleasant surprise..and under $100

Here's a Youtube review

 

[Erhard-Audio]

do note, most of these small preamps, which is wall power packs to runt hem, the tubes are really not doing much at all, at best, they are used as buffers, at worse, they do nothing at all, only the filaments are connected to 'pretend' they are doing something!
Most noval preamp tubes need to run at 150VDC and up, in order to operate properly at their design specs. In cases like these, you get what you pay for!
They may sound OK, but that is achieved using either transistors or small op-amps.

 

[ktm_2000]

I listened to my new to me amp with the KEH speakers for a couple hours tonight with my yamaha as a pre-amp on pure direct, crappy cables and a cheese-ball DVD player as the source. The KEH driven by that amp is quite amazing. The sound is crisp and very clear, There isn't as much of a soundstage effect as my B&Ws so I think a tube amp is the way to go but I would like to hear one in person to know its the right thing for me.

I've been reading the threads about the @$300 china pre-amps - most of the folks seem to like them. Along with kappclark's suggestion, it has got me thinking of the concept of miss right now versus miss right, as I've bought a lot of turds in my audio buying career, I may want to research this quite a bit more before I plunk down a good amount of cash. I haven't gone into an audio shop in years and may want to do so, if they let people in these days. <$100 for a model like kappclark mentioned or $300 for a china model won't hurt the wallet and let me listen while I figure out what I like.

 

[opnly bafld]

@ktm_2000

What are KEH speakers?
The only thing I find is Pioneer car speakers.

 

[StepheK]

do note, most of these small preamps, which is wall power packs to run them, the tubes are really not doing much at all, at best, they are used as buffers, at worse, they do nothing at all, only the filaments are connected to 'pretend' they are doing something!
Most noval preamp tubes need to run at 150VDC and up, in order to operate properly at their design specs. In cases like these, you get what you pay for!
They may sound OK, but that is achieved using either transistors or small op-amps.

This 100%. So many of these just put the filaments in a voltage path so it looks like they are doing something, and removed it doesn't work, so people believe they are tube devices.

Honestly, real tube pre-amps are tough to get quiet, especially a phono stage, and most designs have multiple coupling capacitors, which being in the audio path need to be high quality to sound good. I'm not sure a cheap china made one is gonna fit that bill. Also know most of the "ChiFi" tube gear has transformers wound for 110V, which can be a problem when used with a 120-125V outlet.

Don't mean to discourage you, but do your research!

 

[FlaCharlie]

do note, most of these small preamps, which is wall power packs to runt hem, the tubes are really not doing much at all, at best, they are used as buffers, at worse, they do nothing at all, only the filaments are connected to 'pretend' they are doing something!
Most noval preamp tubes need to run at 150VDC and up, in order to operate properly at their design specs. In cases like these, you get what you pay for!
They may sound OK, but that is achieved using either transistors or small op-amps.

While there certainly are some Chinese preamps that fit your description, the FX and its cousins are actually preamps whose tubes produce gain.

Although they are often referred to as "buffers" when listed for sale, they are not, they have gain. In fact, the most common issue that users seem to have is that there is too much gain, which limits the useful range of the volume control. Of course, most modern amps don't need a preamp at all, they can usually be driven to full power directly from a line level source, so all that is really needed is a volume control aka "passive preamp".

It's a basic anode follower circuit, no transistors are used, at least in the audio portion of the circuit. The original version (01) had no op-amps. The more recent ones use op-amps for the tone controls that were added in some of the later models.

Unlike the cheap Chinese tube amps, they don't have power transformers. Power is supplied by a wall wart or many people upgrade to an external linear PS.

I don't own one but when I was breadboarding a preamp a while back I tried the same tube and circuit using both the (low) voltages found in the stock FX and more normal voltages, as outlined in the tube data sheets. It sounded much better at normal voltages but it wasn't too bad at the stock FX voltages, better than I expected. They have a large and loyal following.

There's a huge thread on them here:

https://www.audiokarma.org/forums/index.php?threads/fx-audio-6j1-tube-preamp-a-31-wonder.848535/

 

[Erhard-Audio]

While there certainly are some Chinese preamps that fit your description, the FX and its cousins are actually preamps whose tubes produce gain.

Although they are often referred to as "buffers" when listed for sale, they are not, they have gain. In fact, the most common issue that users seem to have is that there is too much gain, which limits the useful range of the volume control. Of course, most modern amps don't need a preamp at all, they can usually be driven to full power directly from a line level source, so all that is really needed is a volume control aka "passive preamp".

It's a basic anode follower circuit, no transistors are used, at least in the audio portion of the circuit. The original version (01) had no op-amps. The more recent ones use op-amps for the tone controls that were added in some of the later models.

Unlike the cheap Chinese tube amps, they don't have power transformers. Power is supplied by a wall wart or many people upgrade to an external linear PS.

I don't own one but when I was breadboarding a preamp a while back I tried the same tube and circuit using both the (low) voltages found in the stock FX and more normal voltages, as outlined in the tube data sheets. It sounded much better at normal voltages but it wasn't too bad at the stock FX voltages, better than I expected. They have a large and loyal following.

There's a huge thread on them here:

https://www.audiokarma.org/forums/index.php?threads/fx-audio-6j1-tube-preamp-a-31-wonder.848535/

no doubt, there are some good Chinese amps and preamps out there, yet still, many use cheap parts, especially capacitors and transformers. I personally have no interest in buying such units, for obvious reasons ;-), but the better Chinese units are a good way to get into tube audio without having to spend big $!

 

[Lavane]

I've seen those cheap motor run film caps for things like ceiling fans used in Chinese gear.

 

[FlaCharlie]

I am looking for a pre-amp and would like to expand my horizons into the tube arena. . . . I would like to have a 2nd pure listening setup - plain 2 channel stereo, listen to cds, potentially add a DAC and turntable

I realize I need to spend a bit more on the pre-amp to get something quality but don't want to spend much more than 1k and looking for recommendations on the lower end of tube pre-amps.

Am I better off looking for an old tube setup or something new like the schiit freya, or is building one's own from a kit a reasonable way to go without breaking the bank?

I listened to my new to me amp with the KEH speakers for a couple hours tonight with my yamaha as a pre-amp on pure direct, crappy cables and a cheese-ball DVD player as the source. The KEH driven by that amp is quite amazing. . . .

I've been reading the threads about the @$300 china pre-amps - most of the folks seem to like them. Along with kappclark's suggestion, it has got me thinking of the concept of miss right now versus miss right, as I've bought a lot of turds in my audio buying career, I may want to research this quite a bit more before I plunk down a good amount of cash.
. . . <$100 for a model like kappclark mentioned or $300 for a china model won't hurt the wallet and let me listen while I figure out what I like.

If you like the sound of the SS amp you just found and want to try it with a tube preamp, I'd suggest you pick up one of the little FX units. They're so cheap that, even if you end up replacing it with something better, you're unlikely to regret the purchase.

Then, take your time and decide if you need something more expensive.

I haven't gone into an audio shop in years and may want to do so, if they let people in these days.

IMO, that would be the best way to proceed . . . if you're determined to spend much more than you really need to.

There isn't as much of a soundstage effect as my B&Ws so I think a tube amp is the way to go but I would like to hear one in person to know its the right thing for me.

That would be my suggestion - forget about SS and go all tube. I'd suggest a vintage integrated amp. The quality of the transformers (the heart of any amp) is usually excellent and, unlike new gear, vintage gear actually appreciates in value.

 

[peguinpower]

A used Jolida Fusion preamp can be had from 400-750. Ive had one and its a great starter that comes with remote.

I solde my Inspire LPA tube pre for about 800. An excellent preamp with no remote.

Theyve gone up in price but the Conrad Johnson PV-10A was going for 700-800 before COVID.

These are some Ive owned under 1000.

If you are flexible, sell all your amps and preamps and buy a Willsenton R8 integrated. Its an excellent amp for 1250

Good luck.

 

[ktm_2000]

I appreciate everyone's advice. I am thinking that more research is needed no matter what

here's a link to the speakers I am using - https://us.kef.com/explore-kef/kef-museum/1980s/reference-series-model-1042-1984-96

yes - I am a knucklehead and can't read anymore KEH /KEF, my in close vision is shot and I definitely need glasses for close up reading

the lexicon 412amp is 120w x4 the research I've done states that is very underrated. I would agree with that as the yamaha rxv-1500 surround sound amp I have for surround sound is supposed to have the same wattage but there is a night and day difference between the 2.