Tube Preamp Buffer - TOUR!

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tortugaranger

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Re: Tube Preamp Buffer - TOUR!
« Reply #40 on: 22 Mar 2017, 08:40 pm »
While not part of the tour per se we're starting to get feedback from tube buffer customers. Here's one that came in today on a balanced buffer used together with our LDRxB Balanced Passive Preamp.

Quote
There is an unmistakable quality of "you are there" in the room or hall with the musicians using this unit. It ups the ante in that regards from the preamp alone which was great to begin with. This makes for the first "active" preamp I've ever had that doesn't color the sound in some way. This is why I went to passives long time ago (ModSquad Linedrive) or later to integrated amps. Mission accomplished is right -  in spades.  (Randy Brown)

glynnw

Re: Tube Preamp Buffer - TOUR!
« Reply #41 on: 11 Apr 2017, 05:54 pm »
Just shipped the buffer off to next person.  Having used only a passive preamp for several years, I realize I was wrong in thinking any electronics at this stage would hurt the sound.  I really liked the sound from this piece.  I am not a good reviewer.  I really don't listen for any particular aspects of the sound.  In this case, it just all sounds noticeably better.  Every thing sounds fuller - more fleshed out if you will.  After almost 50 years in this hobby, I have reached the point that all I care about is if it makes me happy.  This buffer does that in spades.

Randy

Re: Tube Preamp Buffer - TOUR!
« Reply #42 on: 11 Apr 2017, 10:02 pm »
Slow moving tour.

tortugaranger

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Re: Tube Preamp Buffer - TOUR!
« Reply #43 on: 12 Apr 2017, 12:31 pm »
Slow moving tour.

I sent the buffer back to the barn for some upgrades and then shipped it out again. That ate up a couple of weeks.

tortugaranger

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Re: Tube Preamp Buffer - TOUR!
« Reply #44 on: 22 Apr 2017, 01:18 pm »
Hi All,

Here's an update on the tour. We started off moving along nicely and then I called the buffer back for an upgrade which ate up a couple of weeks. Now it's bogged down with a couple of participants taking a couple of weeks each. Ozarktom promised to ship it onwards yesterday (4.21.17) but have no confirmation that happened.

dburna you are up next.

Also, finally had an opportunity to build a buffer unit using the optional Vishay metal-foil resistors in the signal path. To my ears it raised the bar just that much higher with a sweeter clarity. Pricey little buggers and frankly I had my doubts but the first few notes of music really got my attention.

1) golfrod - CA
2) 33na3rd - WA
3) konut - WA (moved to end of tour due to DAC being unavailable)
4) dracule1 - TX
5) glynnw - LA
6) ozarktom - MO
7) dburna - IL
8 ) tjhub - WI
9) mitch2 - MI
10) wirenut - OH
11) rklein - OH
12) rustyjefferson - MD
13a) konut - WA 
13b)
slefley - WA

Standby folks in case someone drops out:
1) keven1031
2) skakeydeal
4) JerryM
5)

tortugaranger

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Re: Tube Preamp Buffer - TOUR!
« Reply #45 on: 26 Apr 2017, 12:33 pm »
The buffer is now with dburna in IL for the next few days.
tjhub in WI you are next!

1) golfrod - CA
2) 33na3rd - WA
3) konut - WA (moved to end of tour due to DAC being unavailable)
4) dracule1 - TX
5) glynnw - LA
6) ozarktom - MO
7) dburna - IL

8 ) tjhub - WI
9) mitch2 - MI
10) wirenut - OH
11) rklein - OH
12) rustyjefferson - MD
13a) konut - WA
13b) slefley - WA

Standby folks in case someone drops out:
1) keven1031
2) skakeydeal
4) JerryM
5)

dburna

Re: Tube Preamp Buffer - TOUR!
« Reply #46 on: 2 May 2017, 06:14 pm »
I was the most recent person to have the Tube Buffer in my system.  Just shipped it off to the next AC member today.  I was also fortunate to have the ifi ITube2 in my system for a short while for a head-to-head comparison.  It wasn't close -- the Tortuga has it all over the iFi....which it really should at 5x the price.

I'm not going to rehash what has been said already except to mention that I agree with it a great deal.  I have a SS system that is very dialed in to provide a high degree of neutrality/accuracy, but it is not cold or sterile in any way.  The Tortuga Tube Buffer provided just a bit more liquidity and image depth to the sound but without much/any sacrifice in detail.  If anything, at times I felt it might have been less distorted than my SS system, but I think that was largely because I was enjoying the midrange so much.

Over time, I feel like maybe -- maybe -- there was a slight softening of transients at both the low and high end.  However, it was a small price to pay in terms of overall musical involvement and presentation.  The engineering behind this is top-notch.  The use of the 6H30 "supertube" provides a dark background and a very clean presentation, even on my 96dB speakers. 

Morten, you have (another) winner on your hands.  I very much appreciated my brief time with the Tortuga and I'm pretty sure it will make the next AC listener a pretty happy camper.

Best regards,  -dB

konut

Re: Tube Preamp Buffer - TOUR!
« Reply #47 on: 3 May 2017, 02:40 pm »
I have been reluctant to post my impressions of the buffer because I only had it for 2 days before I sent it back to Morten and wanted to get my Bryston DAC back before I posted a full review.   dburnas' review prompted me to change my mind. I too had the iFi tube buffer in for review. Both units added a substantial fullness to the presentation that I ascribe to the buffering. What the Tortuga added was quite extraordinary. My system, without a buffer, was like listening from the 50th row. The iFi moved me to the 5th row. The Tortuga moved me to the 1st row. Each instrument took on a 3D  quality whereas I could hear micro-dynamics and intimacy I had never experienced before. dburna called it "image depth". I fully agree. I look forward to getting the unit back to reconfirm this experience.

tortugaranger

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Re: Tube Preamp Buffer - TOUR!
« Reply #48 on: 6 May 2017, 02:07 pm »
The buffer is now with tjhub in WI for the next few days.
mitch2 your are next!

1) golfrod - CA
2) 33na3rd - WA
3) konut - WA (moved to end of tour due to DAC being unavailable)
4) dracule1 - TX
5) glynnw - LA
6) ozarktom - MO
7) dburna - IL

8 ) tjhub - WI
9) mitch2 - MI
10) wirenut - OH
11) rklein - OH
12) rustyjefferson - MD
13a) konut - WA
13b) slefley - WA

Standby folks in case someone drops out:
1) keven1031
2) skakeydeal
4) JerryM
5)

mitch2

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Re: Tube Preamp Buffer - TOUR!
« Reply #49 on: 13 May 2017, 06:07 pm »
I have enjoyed my short time with the Tortuga Audio Tube Preamp Buffer.
It arrived on Wednesday without any issues and I appreciated the solid, no-nonsense design.
Unfortunately, when I saw it was single-ended only, I knew I was going to have trouble integrating it and making the most of my audition since I run all balanced connections and my amps only accept balanced inputs.

My system consists of;
Antipodes DX Level 3
Metrum Pavane DAC Level 3 (Adagio without the volume control)
SMc Audio buffered unity-gain line stage with AN Tantalum resistors (essentially the VRE-1)
Clayton M300 Class A monoblocks
Aerial 9 speakers
Aerial SW12 subwoofers (2 each)

Although I have been interested in Tortuga Audio’s LDR passive preamps, I do not own one.  In addition to my main preamplifier listed above, I have a Goldpoint balanced passive preamplifier, using their latest SMD resistors and also a pair of balanced Endler Attenuators using Yageo metal film resistors.  I mainly used the Tube Preamp Buffer with the Goldpoint passive preamp.

I worked around the connection issue by first connecting the Tube Preamp Buffer inputs directly to the single-ended outputs of the Metrum DAC and then sending the buffer outputs to the inputs of a pair of Jensen transformers that convert single-ended signals to balanced signals.  There is an impedance penalty associated with the conversion but since the input impedance of my Clayton amps is 100K ohms, using the transformers typically works just fine, and much better than rca/xlr adaptors.  The balanced outputs from the transformers were sent to the Goldpoint passive preamp and the balanced outputs from the Goldpoint were sent to the amps, so the attenuation occurred after the buffer.  All the ICs used were 1M or less in length but the set-up was still more complicated than I had hoped.

The good news is that there didn’t seem to be any penalty for the complications.  The Tube Preamp Buffer sounded great.  As others have pointed out, the buffer is absolutely quiet, and surprisingly so since it uses two tubes.  I heard a clean, clear sound, with nice body, nice tone, and realistic dimensionality.   If there were any trade-offs, I thought I noticed a slight softening of the bass, leaning toward roundness and fullness instead of detail.  These effects were not to an extent that detracted from the overall enjoyment of listening to the buffer, which always sounded musical.  Without trying a more direct set-up using the balanced version of the buffer, I will never know what impact the extra cables and transformers had on the sound.

To verify what I was hearing, I took the Tube Preamp Buffer out of the signal chain so the only thing between the DAC and the amps was the Goldpoint passive preamp.  The sound became a touch more dynamic and detailed but also a bit harder, sharper, and overall a little less musical.  In my experience, the clarity of a passive preamp is initially attractive but over time I typically begin to notice a slightly flatter image, less body and tonal color, and maybe a bit less dynamic impact, so I have always gone back to whatever good linestage I had in my system at the time.  The effect seemed a little less pronounced when I had an autoformer unit in my system (the Acoustic Imagery Jay-Sho) but I still liked the sound of my SMc preamp better.    I believe that using an active stage or buffer (which is basically a unity gain active stage) improves impedance matching and optimizes signal delivery to the amplifier.

In a comparison between the Goldpoint/ Tube Preamp Buffer combination and my SMc unity-gain buffered preamp, I preferred the SMc unit and believe it displayed a bit better clarity, definition, dynamics, and tone without giving up dimensionality and fullness, and without displaying any hardness or sharpness.   I have owned close to 30 really good preamps over the past 10 to 15 years and the SMc Audio preamp is the best of the bunch, so for the Goldpoint/ Tube Preamp Buffer combination to be anywhere close sonically is quite an accomplishment IMO. 

In summary, I found the Tortuga Audio Tube Preamp Buffer to be well-built, quiet and to do exactly what it was meant to do, which is to optimize the signal between a passive attenuator or preamp and the amplifier that is being driven.  When used in the signal chain with my Goldpoint passive preamp, it improved the flavor of the Goldpoint by providing a richer sounding tone and adding fullness and a touch of roundness that made listening to music more enjoyable.  While these differences were not like night and day, they were noticeable to the point where I believe I would be satisfied long-term with the sound of the Goldpoint preamplifier/ Tube Preamp Buffer combination, but not with the Goldpoint alone.  However, the Goldpoint/ Tube Preamp Buffer combination was not good enough to displace my SMc preamp.

I believe the Tortuga Audio Tube Preamp Buffer is a really good product that may be almost essential for people using passive preamps or attenuators alone.  At a minimum, folks using passives should at least try the tube buffer.   I would like to try the balanced version someday.  IMO, Tortuga Audio could turn a triple into a home run by combining the Tube Preamp Buffer with their LDR passive preamp for a unity-gain, buffered, one-box preamp solution.  Offer balanced and single-ended options with a volume display and remote and the result would be likely to compete with some really good preamps.

Thank you for the opportunity to audition the Tube Preamp Buffer. I plan to ship it out to wirenut on Monday.

tortugaranger

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Re: Tube Preamp Buffer - TOUR!
« Reply #50 on: 14 May 2017, 11:12 am »
mitch2 thank you for your thoughtful review.
The buffer is sooon on its way to wirenut in Ohio this week. 

1) golfrod - CA
2) 33na3rd - WA
3) konut - WA (moved to end of tour due to DAC being unavailable)
4) dracule1 - TX
5) glynnw - LA
6) ozarktom - MO
7) dburna - IL

8 ) tjhub - WI
9) mitch2 - MI
10) wirenut - OH
11) rklein - OH
12) rustyjefferson - MD
13a) konut - WA
13b) slefley - WA

Standby folks in case someone drops out:
1) keven1031
2) skakeydeal
4) JerryM
5)

WireNut

Re: Tube Preamp Buffer - TOUR!
« Reply #51 on: 14 May 2017, 12:59 pm »
mitch2 thank you for your thoughtful review.
The buffer is sooon on its way to wirenut in Ohio this week. 

1) golfrod - CA
2) 33na3rd - WA
3) konut - WA (moved to end of tour due to DAC being unavailable)
4) dracule1 - TX
5) glynnw - LA
6) ozarktom - MO
7) dburna - IL

8 ) tjhub - WI
9) mitch2 - MI
10) wirenut - OH
11) rklein - OH
12) rustyjefferson - MD
13a) konut - WA
13b) slefley - WA

Standby folks in case someone drops out:
1) keven1031
2) skakeydeal
4) JerryM
5)


I'm ready  :thumb:

WireNut

Re: Tube Preamp Buffer - TOUR!
« Reply #52 on: 16 May 2017, 08:34 pm »
The buffer arrived safe and sound today :thumb:. I like the build quality, Solid and Heavy.
I will be swapping it out with my 2 Yaqin CD3 tube buffers that use 6SN7 tubes.
I use one buffer after my phono stage, and a second buffer after my Dac.
The rest of my system is solid state, bi-amped.

I've already hooked it up to my phono stage and listened to 1 Robert Plant tune.
Glorious :o, much better then the Yaqin's right off the bat. Even with nice tubes in the Yaqin.

More about that later in a review. I'm off for some listening time.

Steve.

tortugaranger

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Re: Tube Preamp Buffer - TOUR!
« Reply #53 on: 16 May 2017, 10:02 pm »
The buffer arrived safe and sound today :thumb: . I like the build quality, Solid and Heavy.
I will be swapping it out with my 2 Yaqin CD3 tube buffers that use 6SN7 tubes.
I use one buffer after my phono stage, and a second buffer after my Dac.
The rest of my system is solid state, bi-amped.

I've already hooked it up to my phono stage and listened to 1 Robert Plant tune.
Glorious :o , much better then the Yaqin's right off the bat. Even with nice tubes in the Yaqin.

More about that later in a review. I'm off for some listening time.

Steve.

I've tried 6CG7 tubes (9 pin equivalent to 6SN7 octals)  in the buffer and can confirm that they worked with no noticeable issues. Their gain was probably different but not so you'd notice right off compared to the 6H30's.

WireNut

Re: Tube Preamp Buffer - TOUR!
« Reply #54 on: 19 May 2017, 11:49 pm »
 A couple years ago the need for a new furnace forced the sale of my audio research / sonic frontiers tube gear and since then I’ve put together
a less expensive vintage SS system with the addition of 2 Yaqin CD3 tube buffers. Using tube buffers has added to the enjoyment and I’ll be keeping
my setup this way for a long time.

As mentioned earlier I use one Yaqin tube buffer after my Vista phono-2 and a second after my DAC.
A lot of time rolling 6SN7 tube’s in the Yaqin’s I've found some pretty good ones.

Installing the Tortuga tube buffer in place of the Yaqin after my phono stage was an eye opener.
Sound stage, channel balance, instrument definition, treble and mid range now have more energy and detail.

At first, I thought the added treble and midrange definition was a bit much but after more listening I came to enjoy it.

A couple of questions / thought’s I’d like to ask Morten.

First, as can be seen in my setup it’s easy to turn on the rear power switch but in a different setup a switch located on the front would be better.

Second, and this is probably not possible, since I have so many 6SN7 tubes is it possible to use them with an adapter in the Tortuga?

When the time comes to replace my above buffer’s I’ll be thinking “Tortuga”.

I really like the Tortuga tube buffer and would like to thank Morten for this opportunity.

I’ll be shipping the buffer off to rklein next Wednesday the 24th.

Enjoy and thank you,
Steve 





tortugaranger

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Re: Tube Preamp Buffer - TOUR!
« Reply #55 on: 20 May 2017, 12:25 pm »
Hi Steve,

Thank you for participating in the tour and for taking the time to post your thoughts.  :D

Regarding your two questions:

1) No Switch On Front Panel
- I agree this would be convenient. The reason there isn't one entirely a practical matter of there being no room for one within the constraints of our standard extruded enclosure. We packed quite a bit of hardware into that little black box. On the other hand, we did provide an indirect work-around to this limitation. While not present/functional in the prototype version out on tour, the final version of the tube bufffer has a 12V Trigger input jack in the rear which when plugged into the 12V Trigger output of any of our LDR passive preamps makes the turn on/off of the tube buffer fully automatic. When initially turned on via the 12V Trigger input, the front panel light will blink for approximately 10 seconds during which time the output remains muted and the tube heaters warm up. At around 8 seconds, the plate voltage is turned on and at 10 seconds the muting is turned off. This ensures no speaker "bumps" or sonic artifacts while the tubes power up. Similarly, when turned off the buffer output immediately mutes.

2) 9 pin to octal tube adapter -  While the tube buffer can accept alternative tubes like a 6CG7 (9 pin equivalent to the octal 6SN7), using an a 6SN7 directly would require a 9 pin to octal adapter that also fits into the 1" diameter tube hole in the enclosure. While there are numerous examples of octal-to-9-pin adapters to be found, there are very few 9-pin-to-octals adapters available. There may well be one out there but a quick search suggests otherwise. 

Cheers,  :thumb:
Morten


A couple years ago the need for a new furnace forced the sale of my audio research / sonic frontiers tube gear and since then I’ve put together
a less expensive vintage SS system with the addition of 2 Yaqin CD3 tube buffers. Using tube buffers has added to the enjoyment and I’ll be keeping
my setup this way for a long time.

As mentioned earlier I use one Yaqin tube buffer after my Vista phono-2 and a second after my DAC.
A lot of time rolling 6SN7 tube’s in the Yaqin’s I've found some pretty good ones.

Installing the Tortuga tube buffer in place of the Yaqin after my phono stage was an eye opener.
Sound stage, channel balance, instrument definition, treble and mid range now have more energy and detail.

At first, I thought the added treble and midrange definition was a bit much but after more listening I came to enjoy it.

A couple of questions / thought’s I’d like to ask Morten.

First, as can be seen in my setup it’s easy to turn on the rear power switch but in a different setup a switch located on the front would be better.

Second, and this is probably not possible, since I have so many 6SN7 tubes is it possible to use them with an adapter in the Tortuga?

When the time comes to replace my above buffer’s I’ll be thinking “Tortuga”.

I really like the Tortuga tube buffer and would like to thank Morten for this opportunity.

I’ll be shipping the buffer off to rklein next Wednesday the 24th.

Enjoy and thank you,
Steve 




WireNut

Re: Tube Preamp Buffer - TOUR!
« Reply #56 on: 20 May 2017, 04:53 pm »
The Tortuga buffer has spoiled me. I removed it and put back in the Yaqin buffer and it sound's like crap.  :(

tortugaranger

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Re: Tube Preamp Buffer - TOUR!
« Reply #57 on: 20 May 2017, 10:22 pm »
The Tortuga buffer has spoiled me. I removed it and put back in the Yaqin buffer and it sound's like crap.  :(

Got a solution for that Steve.  :thumb:

rklein

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Re: Tube Preamp Buffer - TOUR!
« Reply #58 on: 8 Jun 2017, 03:07 pm »
I received the Tortuga Tube Buffer and had the pleasure of it in my system for about 6 days.  I had to put the buffer between my Holo DAC and the Bent TAP passive pre I am using.  The reason for this is that the XLR to RCA adapters that I bought for this purpose were too tight a fit on my NORD One Up Monos.

Anyway, listening in this configuration was very pleasing to me.  With the buffer in place, there was a change for the better in regards to the tone and tambre of orchestral instruments.  Woodwinds, strings and even brass had a bit more depth.  I played some complex orchestral pieces and with the buffer in the chain, I was further drawn into the sound being reproduced than sans the buffer.

The Tortuga buffer did not add a bunch of "tube goodness" to the sound.  Rather, it enhanced the presentation by bringing the artists a bit closer to you.  If you are running a SS system and listen to classical, this piece is worthwhile to try in your system.

My room is 14' by 14' with a drop ceiling.  I have to be in a near field configuration with the speakers pulled out a good four feet from the front wall and three feet from the side walls with my listening position 7 feet from each speaker in a trilateral setup.  This being the case, amplified bass on R&B, rock, even some jazz pieces sounded too loud and a bit unrefined in my smallish room.  This could absolutely change if listening in a larger room.  However, I have what I have and this problem did not rear it's ugly head on most acoustical recordings.

I don't have other tube buffers to compare the Torgtuga to but overall I was pleased with the changes the buffer brought to my listening experience.

The shipping box was a bit beat up so I had FedEx double box the unit and sent it off to Rusty in Maryland who received the unit yesterday.

Thanks for allowing me to participate in the tour!  :thumb:

Regards,

Randy

Rusty Jefferson

Re: Tube Preamp Buffer - TOUR!
« Reply #59 on: 17 Jun 2017, 06:40 pm »
I had the pleasure of using the Tortuga buffer last week in my system as part of this tour.  Thanks to Morten for giving me the opportunity to audition one of his components in my system.  Very generous, indeed.

I tried using a buffer in my system for the first time about a year or so ago when I became concerned that bi-amping with 2 solid state amplifiers that had moderate input impedance, and a tube preamp with normal moderately high output impedance, was holding back dynamic performance. Sure enough, as soon as I installed it (original iTube buffer) between preamp and amplifier, the system just came to life. Improved bass punch, dynamics, drive, etc.  I then replaced my tube preamp with a First Sound passive, as I didn't need the gain from the active and the tube circuit in the buffer was giving me the linear presentation I am after without being "tubey", but was also less "hard" compared to solid state preamps (which have low output impedance) I tried.  The noise floor with my 102db efficient speakers became virtually silent as a result. I have not tried any other brands of buffers until the last month when I tried the Tortuga buffer and the new iTube 2 as part of the tours.

The Tortuga buffer arrived set to (I believe) 6db of gain.  Morten says it is internally switchable to 0db, or 3db, also.  I didn't ask to change it. Like the Original iTube I'd been using, and the iTube 2, the low output impedance of the Tortuga buffer gave it the ability to drive both the amplifiers easily, giving me the big dynamic sound I enjoy.  It also has an exceptional midrange quality.  Very refined, and natural.  Instinctively, I was drawn to playing vocal tracks, and was impressed with the rich, textured presentation.  I used the supplied EH 6H30s, and a pair of 6H30-DRs, and also a pair of Tung Sol 6CG7s. I felt the DRs had the nicest midrange, and the 6CG7s had the best extension. 

For me, and in my system, there was a shortcoming however.  There was a small attenuation of high frequencies that made the presentation very smooth, but removed the micro detail and "air" I'm used to hearing, out of the system.  It is the classic "midrange magic" vs. "inner detail" debate. My preference is toward the detail side.  I want full frequency extension. A friend who listened with me last week preferred the Tortuga's silky smooth presentation over the iTube, and I preferred the clarity and extension of the iTube. 

I think this buffer could be an excellent addition for people looking for "tube magic" in their system without getting into tube amplifiers/preamps, as well as anyone bi-amping, who may benefit from better impedance matched components.