Jeb Listens
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The WA7 + WA7tp & LCD-2.2F : DAC shoot-out & power supply tube guide.
** This review has also now been updated with a tube guide part 2 on page 4 of this thread **
Part 1: The WA7 DAC/AMP
Rather than re-hash what has already been said about this nice little amp, I was more interested to assess the performance of the onboard WA7 Fireflies DAC by comparing it with the other few I have at my disposal. However it is important to remember that I am only judging the WA7 against the very few amps and DACs that I own, which is not the same as placing it in the landscape of all the other headphone equipment out there. Please keep that in mind and carry out your own research & demonstrations.
All Comparisons done with LCD2.2-Fazors.
WA7 Dac vs a portable DAC: Fostex HP-P1
The HP-P1 (+/- £500 rrp) is a pretty nice and smooth DAC with a relatively (for a portable) expansive 3D soundstage. I’ve previously tested the Fostex in a few set-ups, including my modest 2-channel set-up and have been quite impressed.
I found the HP-P1 and the WA7’s DAC to have a largely similar presentation – neither one too forward nor too relaxed, presenting the music with acceptable realism and coherence.
There are many, many passages within my chosen albums where the disparity between the DACs was completely negligible. It took a good 20-30 minutes of intense concentration on just a couple of small passages of music to begin to discern a few minor differences. Even though the Fostex and WA7 DACs share a similar width and depth of soundstage, I did begin to notice that the Fostex DAC provides a slightly better degree of instrument separation and imaging than the WA7. In addition, there is an extra sparkly and airy quality to the treble via the Fostex that sees the WA7 lagging (slightly) behind.
It seemed as though the smaller details of atmospheric tracks were perhas being lost via the WA7 DAC. Listening to the climax of Hey Now by London Grammar, both DACs did a great job of rendering the vocal but with the Fostex I felt a little more micro-detail was being retrieved resulting in an extra soaring quality that was more enjoyable to me.
I would say overall both DACs share a similar level of transparency. However, using the WA7 Dac there is unfortunately a touch of grain in the vocals at times. I noticed this the very first time I used the units and can now trace it to the DAC rather than the Amp. In terms of overall smoothness, I would probably again give the nod to the Fostex, which is slightly more relaxed through the mid section. The Woo is livelier, more dynamic and agile than the more laid-back Fostex – the latter plays more to my personal tastes and prevents the sound from feeling strained.
WA7 vs an entry level desktop DAC - Schiit Modi ~£90
The Modi performed admirably through the WA7 amp. Yet, on returning to the WA7’s on-board DAC there was something immediately more pleasing about the presentation. Guitar strings had more life, more elastic and the music in general had a greater degree of coherence and engagement-factor than the Modi, which felt altogether more restrained.
The WA7 is by no means a “forward” or “in-your-face” DAC but I felt that through the Modi mids and vocals took a step further back sacrificing some of the immediacy and fun of the music.
Switching to John Martyn’s album One World, the WA7 DAC maintained the upper hand in its ability to balance a richness in the vocals with an enjoyable sparkle and delicacy in the high end. Further still, the WA7 DAC soundstage is a little wider and deeper than the Modi. When I listened to the multi-effects track Big Muff by John Martyn I felt that details, atmospherics and note-decay were a little obscured in the Modi’s more congested presentation.
Where I had struggled to discern truly meaningful differences between the Fostex and the WA7, the latter seems a couple of steps up the ladder from the Modi. With further listening and comparisons I could appreciate the WA7 Dac’s ability to remain both dynamic and warm, despite it's other weaknesses.
WA7 DAC Vs a Mid-Fi desktop DAC - Rega Dac
I cannot comment that the Rega is a "great" or even a "very good" DAC but its the best one I have. Please keep that in mind.
The Rega Dac through the WA7 is pretty good! There’s a slightly wider soundstage, more sparkle and a richer tone throughout but what I enjoy most is the Rega's coherent sound. It has a head-nodding, toe-tapping rhythmical quality that creates a lifelike 3D musical image then pops you right in the front row.
When comparing the WA7 DAC to the Rega Dac there’s an extra silkiness to the Rega and the scale of the experience feels greater. It also somehow manages to feel more intimate and engaging - when necessary - than the Woo. I found myself connecting with the music and getting lost in it significantly more often with the Rega DAC. With the WA7 I could categorise the sound as being smaller, thinner and more “metallic” than with the Rega, with which everything feels as though it is more liquid. Music feels bigger, smoother and richer through this DAC.
While the WA7 DAC cannot offer this richness of sound it is marginally more lively and dynamic in presentation. I must admit, the Rega again plays more to my tastes and is an engaging DAC in its own way.
When I cued up Blood Orange’s most recent album Coastal Grooves there was a depth and extension to the bass that the WA7 DAC could just not live with although it did a reasonable in its own right.
Rega Dac & Schiit Asgard vs WA7 Dac/Amp
Keeping the Rega Dac as the front end, I hooked up an Asgard 2 from Schiit and started to compare with the WA7 Dac/Amp unit as a whole. The Rega/Schiit/ set-up would be the cheaper option, coming in under £800, while the WA7+TP is more like £1200 once you factor in VAT/import etc to the UK.
For me, the Rega DAC combo with the Asgard 2 cannot compete with the WA7. The Asgard is outstanding value for money and a very proficient amp but in comparison with the WA7 I feel it suffers from the same problem as the Modi – that is to say a bit of “dullness” to the sound; the Asgard is more mechanical. One thing to bear in mind is that some people believe that in practice the Asgard does not possess the power to properly drive the LCD-2s, although 'on paper' I believe it does - at least for my own listening levels.
The Schiit did a good enough job that I was still appreciate the benefits of the Rega-DAC. The pairing retains the warmth, immediacy and richness of the Rega bit it also suffers from feeling like the music is compressed and is having some of the life knocked out of it. By contrast, the quality of the WA7 Amp is perhaps able to elevate its lesser DAC to an overall more enjoyable package.
It wasn’t all sunshine with the WA7 amp+DAC. Again, the amp reveals a degree of grain and strain in the sound of its on-board DAC. As much as the music flowed better than through the Rega/Schiit pairing, there’s sometimes a slight thinness and hollowness that detracts from the experience. The WA7 can certainly benefit from a better DAC than its own on-board unit but that raises a separate value question.
Conclusions
So how good is the WA7 DAC? Well, at least compared to the others I own, it proved its worth as part of the total package. For whatever reason, with my own gear I don't see as big a disparity between the performance of the amp and the DAC as some people. Within my comparisons with the small selection of equipment available to me, I had found it to sit right in the middle ground between a good entry-level DAC (modi) and a better quality mid-fi desktop unit (Rega). The on-board DAC would probably serve many of its users perfectly well, especially if they are starting out.
However, despite its abilities I can understand that the DAC’s performance - and many forum discussions could leave its users somewhat in a no-man’s land with the knowledge that to get the very best from their unit they will need a DAC upgrade right off the bat. In this sense, the WA7 is a victim of having a good amp section and also somewhat proves the point of many that all in one units are usually a compromise of some sort. Yet, the fact that the WA7 can scale well with a better DAC, but that the DAC is also acceptable to many, means it may be endgame to some and a convenient stop-gap to others.
As funds permit you could explore a different DAC – but it would be important to retain good perspective about how much is reasonable to spend on a DAC to feed a £1000 amp and whether it might be better to rejig the whole set-up once you have outgrown it.
Part 2: Tube Guide.
Before we begin- I need to state that for those looking to simply maximise sonic fidelity, excessive tube-rolling in the WA7 or over-paying for many unobtanium tubes, especially in this instance, is usually an extremely inefficient use for your money.
Many people are quite passionate about trying many different flavours and I respect that -it can be fun, but I would not want to give the impression that spending multiple-hundreds of pounds on rare tubes is sensible vs simply upgrading your headphones or other equipment in your chain. Changing your headphones is almost always the best way to bring the biggest changes and these tube-rolls will be unlikely to turn a headphone you dislike into one you love.
Find a balance and be realistic about the magnitude of the changes you can expect - in my experience, during typical, relaxed listening sessions, the changes will be nowhere near as big as you imagine them to be when you are 100% focused on the differences between tubes. Remember that the changes I am describing are also changes relative to the other tubes.
Hopefully this guide will help you zero in on one or 2 tubes to try and be happy with.
1. Bang for Buck - Sylvania JAN 5814A
I think the first thing many WA7 owners will notice when making this change is a warmer, fuller, meatier sound that is simultaneously cleaner while also providing an improvement over the slightly grainy and one dimensional stock 12au7s.
Using the WA7 Dac the JAN 5814As helped to mop up some of the thinness I had heard earlier. The sound was a little richer. Since the WA7 DAC and Amp are both pretty lively and agile, adding in a bassier and warmer tube like the JANs is a nice way to balance the sound and put a little more meat on the bones.
The JANs can occasionally get a bit bloomy in the low-end but certainly not at all as much as I expected them to. All in all, they were a more balanced fit with the WA7 stock DAC, which placed the music right in the sweet spot. The top end is mostly well focused and always stops short of ever sounding too “hot”.
On a tight budget, at approx. £8 per tube, It’s probably one of the best and easiest upgrades you could ever make for the WA7, especially if you will be using the on-board DAC. These tubes will help smooth over a major gripe with the WA7 Dac, which is the grain and hollowness that appears in vocals.
2. Cifte 12AU7.
A quirky looking set of 1962 military-spec 12AU7s tubes from Cifte. There’s a huge price jump from the JANS with these tubes going for around £70 a pair. I believe some of these tubes may also be branded “Mazda” but I cannot confirm if they sound the same.
Just as the Sylvanias did, the Ciftes smooth over the grain of the WA7 Dac and make the sound more substantial but they do it with a superior degree of finesse and with less body overall. The sparkle in the top-end is really excellent at times.
The air, separation and precision of this tube is its major strength.
For me, these tubes are bang on for balance and poise. However, I do wonder if via the WA7 DAC/Amp you might find yourself craving a little more body to the music.
3. Best all-rounder: the Mullard CV4003
This is a mid-priced military spec ex-RAF tube that can be obtained from anywhere between £35 and £60 a tube, so at best the same price as the Ciftes.
These tubes pack a good punch and are a solid rather than airy sounding tube. Again there is more body to the sound than with the stock 12AU7s. Where they differ from the JANs is their superior degree of naturalness and realism in instrument and vocal timbre and tone.
The CV4003’s don’t possess the magical sparkle and top-end of the Ciftes, but there is a pleasant warmth and richness to their sound. Mids and vocals have a different tone than the Ciftes –full bodied, smoother, but slightly less wide, soaring and airy and resolved in the treble. One element that really stands out is the note-decay on instruments (particularly guitar strings and piano) which have a noticeable realism. They have a slightly mid-centric, sometimes overly-warm sound which isn't for everyone.
In terms of value, the Mullard CV4003s are now hitting heights of $100 per tube, 10x the price of the Jan 5814as – and they are not 10 times better.
NOTE: a few people have posted about recent poor quality/untested/used/possibly fake CV4003s with high-failure rates showing up on eBay but being sold as NOS. ...be cautious and do your due-diligence, as ever. You can always check with the Head Fi'ers over on the WA7tp thread for advice.
4.New Production - Psvane 12au7
The Psvane 12AU7, a current production tube from China with a mixed reputation. These are not “cheap” at around £70 for a matched pair.
In certain areas, these tubes continued to impress. The soundstage vs the Mullards was improved, which was most welcome for the LCD-2s. Likewise, instrument separation was a bit bette. The Psvanes did a better job of creating a wider holographic experience.
I think where these tubes fall down is they go too far the other way from the Mullards and can sound too thin and metallic in the mids and vocals. They also sound too aggressive for my tastes. Even switching to the Rega Dac couldn’t smooth out some of these issues. This is a tube that gets a bit tiring to listen to after a while. Probably not a good match for the WA7 stock DAC, I have to say.
The Electro Harmonix Gold-Pin debate.
Right from the beginning, opinion on these tubes ranged from one of the most impactful tube rolls ever made to a complete red-herring, which contributed precisely nothing. A quick email exchange with the Tube technician at Sovtek explained that the tubes have the same “electrical specs and operating parameters”. However, I don’t believe that measurements are everything.
The tubes look almost identical in construction with a few notable exceptions. Though both have a halo getter, the EH halo is significantly smaller and is solid in the centre. Thirdly, on the Sovtek there is a tiny wire that leads from the centre of the top plate to one of the pins that supports the getter. This is totally absent on the EH 6C45 Gold Pin tubes.
With my listening, right from the start I can tell that *if* there is a difference in sound it is far more subtle than the tube rolls in the tube power supply.
Over time, I felt I began to detect very minor differences. The EHs have slightly more air, sparkle, separation and clarity. Although each of these improvements are individually very slight, when taken together they contribute to much more of a precise/airy quality than the Sovteks, which now sounded a little more “blunt” and “bloated” in their delivery.
Summing up:
As the sun began to set on my journey with the WA7+TP, I found myself asking the question – where next?
I think perspective is really important.
If you add a better class of DAC to the WA7 and a pair of CV4003s to the power supply you are really at the end of taking the set-up as far as it can go. Further tube rolling could be considered for squeezing out the last few % of performance or tuning the sound to your taste... or else it is mostly for pleasure, vanity, madness or obsession rather than for a really significant performance return for your cash.
If money or space is an issue don’t worry or obsess about the DAC. It’s fine to start and you can use your time with it and the WA7 amp to see if this is going to be your long-term amp or if it will just be another step on the way. I recommend to replace the stock 12AU7s in the TP. There’s not one single easier or cheaper thing you could do to elevate the WA7+TP than to remove them and pop in some $10-15 Sylvania JAN 5814a tubes.
On reflection, the WA7+TP had struck a nice balance between being a no-fuss, no roll amp OR one that would serve as a gateway to grander amps.
You can now find Tube Guide PART 2 on page 4 of this thread: more 12AU7s tested
** This review has also now been updated with a tube guide part 2 on page 4 of this thread **
Part 1: The WA7 DAC/AMP
Rather than re-hash what has already been said about this nice little amp, I was more interested to assess the performance of the onboard WA7 Fireflies DAC by comparing it with the other few I have at my disposal. However it is important to remember that I am only judging the WA7 against the very few amps and DACs that I own, which is not the same as placing it in the landscape of all the other headphone equipment out there. Please keep that in mind and carry out your own research & demonstrations.
All Comparisons done with LCD2.2-Fazors.
WA7 Dac vs a portable DAC: Fostex HP-P1
The HP-P1 (+/- £500 rrp) is a pretty nice and smooth DAC with a relatively (for a portable) expansive 3D soundstage. I’ve previously tested the Fostex in a few set-ups, including my modest 2-channel set-up and have been quite impressed.
I found the HP-P1 and the WA7’s DAC to have a largely similar presentation – neither one too forward nor too relaxed, presenting the music with acceptable realism and coherence.
There are many, many passages within my chosen albums where the disparity between the DACs was completely negligible. It took a good 20-30 minutes of intense concentration on just a couple of small passages of music to begin to discern a few minor differences. Even though the Fostex and WA7 DACs share a similar width and depth of soundstage, I did begin to notice that the Fostex DAC provides a slightly better degree of instrument separation and imaging than the WA7. In addition, there is an extra sparkly and airy quality to the treble via the Fostex that sees the WA7 lagging (slightly) behind.
It seemed as though the smaller details of atmospheric tracks were perhas being lost via the WA7 DAC. Listening to the climax of Hey Now by London Grammar, both DACs did a great job of rendering the vocal but with the Fostex I felt a little more micro-detail was being retrieved resulting in an extra soaring quality that was more enjoyable to me.
I would say overall both DACs share a similar level of transparency. However, using the WA7 Dac there is unfortunately a touch of grain in the vocals at times. I noticed this the very first time I used the units and can now trace it to the DAC rather than the Amp. In terms of overall smoothness, I would probably again give the nod to the Fostex, which is slightly more relaxed through the mid section. The Woo is livelier, more dynamic and agile than the more laid-back Fostex – the latter plays more to my personal tastes and prevents the sound from feeling strained.
WA7 vs an entry level desktop DAC - Schiit Modi ~£90
The Modi performed admirably through the WA7 amp. Yet, on returning to the WA7’s on-board DAC there was something immediately more pleasing about the presentation. Guitar strings had more life, more elastic and the music in general had a greater degree of coherence and engagement-factor than the Modi, which felt altogether more restrained.
The WA7 is by no means a “forward” or “in-your-face” DAC but I felt that through the Modi mids and vocals took a step further back sacrificing some of the immediacy and fun of the music.
Switching to John Martyn’s album One World, the WA7 DAC maintained the upper hand in its ability to balance a richness in the vocals with an enjoyable sparkle and delicacy in the high end. Further still, the WA7 DAC soundstage is a little wider and deeper than the Modi. When I listened to the multi-effects track Big Muff by John Martyn I felt that details, atmospherics and note-decay were a little obscured in the Modi’s more congested presentation.
Where I had struggled to discern truly meaningful differences between the Fostex and the WA7, the latter seems a couple of steps up the ladder from the Modi. With further listening and comparisons I could appreciate the WA7 Dac’s ability to remain both dynamic and warm, despite it's other weaknesses.
WA7 DAC Vs a Mid-Fi desktop DAC - Rega Dac
I cannot comment that the Rega is a "great" or even a "very good" DAC but its the best one I have. Please keep that in mind.
The Rega Dac through the WA7 is pretty good! There’s a slightly wider soundstage, more sparkle and a richer tone throughout but what I enjoy most is the Rega's coherent sound. It has a head-nodding, toe-tapping rhythmical quality that creates a lifelike 3D musical image then pops you right in the front row.
When comparing the WA7 DAC to the Rega Dac there’s an extra silkiness to the Rega and the scale of the experience feels greater. It also somehow manages to feel more intimate and engaging - when necessary - than the Woo. I found myself connecting with the music and getting lost in it significantly more often with the Rega DAC. With the WA7 I could categorise the sound as being smaller, thinner and more “metallic” than with the Rega, with which everything feels as though it is more liquid. Music feels bigger, smoother and richer through this DAC.
While the WA7 DAC cannot offer this richness of sound it is marginally more lively and dynamic in presentation. I must admit, the Rega again plays more to my tastes and is an engaging DAC in its own way.
When I cued up Blood Orange’s most recent album Coastal Grooves there was a depth and extension to the bass that the WA7 DAC could just not live with although it did a reasonable in its own right.
Rega Dac & Schiit Asgard vs WA7 Dac/Amp
Keeping the Rega Dac as the front end, I hooked up an Asgard 2 from Schiit and started to compare with the WA7 Dac/Amp unit as a whole. The Rega/Schiit/ set-up would be the cheaper option, coming in under £800, while the WA7+TP is more like £1200 once you factor in VAT/import etc to the UK.
For me, the Rega DAC combo with the Asgard 2 cannot compete with the WA7. The Asgard is outstanding value for money and a very proficient amp but in comparison with the WA7 I feel it suffers from the same problem as the Modi – that is to say a bit of “dullness” to the sound; the Asgard is more mechanical. One thing to bear in mind is that some people believe that in practice the Asgard does not possess the power to properly drive the LCD-2s, although 'on paper' I believe it does - at least for my own listening levels.
The Schiit did a good enough job that I was still appreciate the benefits of the Rega-DAC. The pairing retains the warmth, immediacy and richness of the Rega bit it also suffers from feeling like the music is compressed and is having some of the life knocked out of it. By contrast, the quality of the WA7 Amp is perhaps able to elevate its lesser DAC to an overall more enjoyable package.
It wasn’t all sunshine with the WA7 amp+DAC. Again, the amp reveals a degree of grain and strain in the sound of its on-board DAC. As much as the music flowed better than through the Rega/Schiit pairing, there’s sometimes a slight thinness and hollowness that detracts from the experience. The WA7 can certainly benefit from a better DAC than its own on-board unit but that raises a separate value question.
Conclusions
So how good is the WA7 DAC? Well, at least compared to the others I own, it proved its worth as part of the total package. For whatever reason, with my own gear I don't see as big a disparity between the performance of the amp and the DAC as some people. Within my comparisons with the small selection of equipment available to me, I had found it to sit right in the middle ground between a good entry-level DAC (modi) and a better quality mid-fi desktop unit (Rega). The on-board DAC would probably serve many of its users perfectly well, especially if they are starting out.
However, despite its abilities I can understand that the DAC’s performance - and many forum discussions could leave its users somewhat in a no-man’s land with the knowledge that to get the very best from their unit they will need a DAC upgrade right off the bat. In this sense, the WA7 is a victim of having a good amp section and also somewhat proves the point of many that all in one units are usually a compromise of some sort. Yet, the fact that the WA7 can scale well with a better DAC, but that the DAC is also acceptable to many, means it may be endgame to some and a convenient stop-gap to others.
As funds permit you could explore a different DAC – but it would be important to retain good perspective about how much is reasonable to spend on a DAC to feed a £1000 amp and whether it might be better to rejig the whole set-up once you have outgrown it.
Part 2: Tube Guide.
Before we begin- I need to state that for those looking to simply maximise sonic fidelity, excessive tube-rolling in the WA7 or over-paying for many unobtanium tubes, especially in this instance, is usually an extremely inefficient use for your money.
Many people are quite passionate about trying many different flavours and I respect that -it can be fun, but I would not want to give the impression that spending multiple-hundreds of pounds on rare tubes is sensible vs simply upgrading your headphones or other equipment in your chain. Changing your headphones is almost always the best way to bring the biggest changes and these tube-rolls will be unlikely to turn a headphone you dislike into one you love.
Find a balance and be realistic about the magnitude of the changes you can expect - in my experience, during typical, relaxed listening sessions, the changes will be nowhere near as big as you imagine them to be when you are 100% focused on the differences between tubes. Remember that the changes I am describing are also changes relative to the other tubes.
Hopefully this guide will help you zero in on one or 2 tubes to try and be happy with.
1. Bang for Buck - Sylvania JAN 5814A
I think the first thing many WA7 owners will notice when making this change is a warmer, fuller, meatier sound that is simultaneously cleaner while also providing an improvement over the slightly grainy and one dimensional stock 12au7s.
Using the WA7 Dac the JAN 5814As helped to mop up some of the thinness I had heard earlier. The sound was a little richer. Since the WA7 DAC and Amp are both pretty lively and agile, adding in a bassier and warmer tube like the JANs is a nice way to balance the sound and put a little more meat on the bones.
The JANs can occasionally get a bit bloomy in the low-end but certainly not at all as much as I expected them to. All in all, they were a more balanced fit with the WA7 stock DAC, which placed the music right in the sweet spot. The top end is mostly well focused and always stops short of ever sounding too “hot”.
On a tight budget, at approx. £8 per tube, It’s probably one of the best and easiest upgrades you could ever make for the WA7, especially if you will be using the on-board DAC. These tubes will help smooth over a major gripe with the WA7 Dac, which is the grain and hollowness that appears in vocals.
2. Cifte 12AU7.
A quirky looking set of 1962 military-spec 12AU7s tubes from Cifte. There’s a huge price jump from the JANS with these tubes going for around £70 a pair. I believe some of these tubes may also be branded “Mazda” but I cannot confirm if they sound the same.
Just as the Sylvanias did, the Ciftes smooth over the grain of the WA7 Dac and make the sound more substantial but they do it with a superior degree of finesse and with less body overall. The sparkle in the top-end is really excellent at times.
The air, separation and precision of this tube is its major strength.
For me, these tubes are bang on for balance and poise. However, I do wonder if via the WA7 DAC/Amp you might find yourself craving a little more body to the music.
3. Best all-rounder: the Mullard CV4003
This is a mid-priced military spec ex-RAF tube that can be obtained from anywhere between £35 and £60 a tube, so at best the same price as the Ciftes.
These tubes pack a good punch and are a solid rather than airy sounding tube. Again there is more body to the sound than with the stock 12AU7s. Where they differ from the JANs is their superior degree of naturalness and realism in instrument and vocal timbre and tone.
The CV4003’s don’t possess the magical sparkle and top-end of the Ciftes, but there is a pleasant warmth and richness to their sound. Mids and vocals have a different tone than the Ciftes –full bodied, smoother, but slightly less wide, soaring and airy and resolved in the treble. One element that really stands out is the note-decay on instruments (particularly guitar strings and piano) which have a noticeable realism. They have a slightly mid-centric, sometimes overly-warm sound which isn't for everyone.
In terms of value, the Mullard CV4003s are now hitting heights of $100 per tube, 10x the price of the Jan 5814as – and they are not 10 times better.
NOTE: a few people have posted about recent poor quality/untested/used/possibly fake CV4003s with high-failure rates showing up on eBay but being sold as NOS. ...be cautious and do your due-diligence, as ever. You can always check with the Head Fi'ers over on the WA7tp thread for advice.
4.New Production - Psvane 12au7
The Psvane 12AU7, a current production tube from China with a mixed reputation. These are not “cheap” at around £70 for a matched pair.
In certain areas, these tubes continued to impress. The soundstage vs the Mullards was improved, which was most welcome for the LCD-2s. Likewise, instrument separation was a bit bette. The Psvanes did a better job of creating a wider holographic experience.
I think where these tubes fall down is they go too far the other way from the Mullards and can sound too thin and metallic in the mids and vocals. They also sound too aggressive for my tastes. Even switching to the Rega Dac couldn’t smooth out some of these issues. This is a tube that gets a bit tiring to listen to after a while. Probably not a good match for the WA7 stock DAC, I have to say.
The Electro Harmonix Gold-Pin debate.
Right from the beginning, opinion on these tubes ranged from one of the most impactful tube rolls ever made to a complete red-herring, which contributed precisely nothing. A quick email exchange with the Tube technician at Sovtek explained that the tubes have the same “electrical specs and operating parameters”. However, I don’t believe that measurements are everything.
The tubes look almost identical in construction with a few notable exceptions. Though both have a halo getter, the EH halo is significantly smaller and is solid in the centre. Thirdly, on the Sovtek there is a tiny wire that leads from the centre of the top plate to one of the pins that supports the getter. This is totally absent on the EH 6C45 Gold Pin tubes.
With my listening, right from the start I can tell that *if* there is a difference in sound it is far more subtle than the tube rolls in the tube power supply.
Over time, I felt I began to detect very minor differences. The EHs have slightly more air, sparkle, separation and clarity. Although each of these improvements are individually very slight, when taken together they contribute to much more of a precise/airy quality than the Sovteks, which now sounded a little more “blunt” and “bloated” in their delivery.
Summing up:
As the sun began to set on my journey with the WA7+TP, I found myself asking the question – where next?
I think perspective is really important.
If you add a better class of DAC to the WA7 and a pair of CV4003s to the power supply you are really at the end of taking the set-up as far as it can go. Further tube rolling could be considered for squeezing out the last few % of performance or tuning the sound to your taste... or else it is mostly for pleasure, vanity, madness or obsession rather than for a really significant performance return for your cash.
If money or space is an issue don’t worry or obsess about the DAC. It’s fine to start and you can use your time with it and the WA7 amp to see if this is going to be your long-term amp or if it will just be another step on the way. I recommend to replace the stock 12AU7s in the TP. There’s not one single easier or cheaper thing you could do to elevate the WA7+TP than to remove them and pop in some $10-15 Sylvania JAN 5814a tubes.
On reflection, the WA7+TP had struck a nice balance between being a no-fuss, no roll amp OR one that would serve as a gateway to grander amps.
You can now find Tube Guide PART 2 on page 4 of this thread: more 12AU7s tested