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A Very Compact Hybrid Amp - Page 55

post #811 of 2204
Quote:
Originally Posted by nux View Post
Finished casing the first one up, hooray! You can see another three in the background ready to be cased up.
SNIP
Case only gets slightly warm after an hours use, so hopefully I wont have to drill any ventilation holes.
Very nice to see some production builds coming together.

Good to hear it's not getting too hot - the large hole around the tube should help. I'd still do a hole over the 24V reg, but if it's staying cool - you're probably fine.

Seems there has been a bit of different experience with heat across the proto builds. Mine gets pretty warm with a full perf top, depending on tube choice.

What tubes are you using?
post #812 of 2204

Cavalli CTH Impressions

I am not doing a full blown review of the Cavalli CTH (compact tube hybrid) - but I will post my impressions so far of its sound and a few comparisons.

I have spent a couple of days with the CTH/Mullard short-plate and find it to be a nice detailed and warm powerful tube hybrid, with above average soundstage and no glaring negatives or complaints in the sound. My main complaints are the lack of a power switch, no RCA input on the rear, and less transportability due to the protruding 12AU7 through the top cover.

I spent some time comparing it vs my Head-direct EF1/stock RCA clear-top 12AU7. One observation was with Giovanni Mirabassi "Prima O Poi" the song Symphomaniax - With HD600 the CTH presented more body to the trumpet, the piano was smoother/refined and more up front, and the sound was mellower overall and slightly darker. But, the sound was also fuller and more refined like you would expect from a bigger amp. In general listening to the CTH was more engaging than the EF1 with stock tube, which seemed a little more distant and presented a slightly less solid image of the instruments.

Switching the EF1 RCA clear top to a Mullard long-plate in the EF1 resulted in the two amps coming much closer together. The EF1 picked up more body and refinement, and became more engaging as well. With the Mullard in the EF1 the treble did become a little more recessed than with the RCA, but not lacking. At this point I cannot pick one amp over the other as the two sound very similar. The volume control on the CTH is much better than the EF1, and I am now convinced that I need to send the EF1 back to have the volume control looked at.

I also compared the CTH to the ALO/RWA Amphora which seems to have a little bit more transparency and detail and yet still has a fairly rich tube-like sound similar to the Cavalli. Yes, sound signatures are somewhat similar but they are not exact. I have not been able to compare their soundstages or bass/treble extension with test tones yet, but I can say the Cavalli has a little too much bass with the Sennheiser IE8 which sound better on the Amphora. I still don't think I would change anything about the Amphora or CTH with most headphones. With the Grado RS-1 the CTH, EF1 and Amphora also seem to come closer to each other in sound. (can't use the IE8 on the EF1 due to the volume control).

Most of the listening has been with my iMod and portable Vcap dock as source (using Soloz 12-strand Litz-braid mini-RCA or my ALO SXC mini-RCA). The RSA P-51 Mustang was velcro'd to my portable Vcap dock, so I tried it out in comparison too. The P-51 has slightly more treble presence than the CTH or EF1 with Mullards or the Amphora, so it's not quite as mellow as them, but that is about the biggest difference. The other thing you notice is the P-51 is a little more forward and energetic or aggressive sounding, but not in a bad way. The CTH, EF1 and ALO Amphora are a little less aggressive and more refined sounding than the P-51, but the P-51 holds up well against them.

The CTH is a good sounding amp and well worth the money and time to build one, and that is all that matters. I (and others) hate ratings, so I am going to nip the requests for one in the bud. Don't ask me. As you can see from my comparisons, it competes well vs other amps costing more, and as an added bonus it can be used with IEM while my son's Millett SSH and my EF1 cannot, due to poor volume controls. (Millett SSH not compared directly this time around)
post #813 of 2204
Quote:
Originally Posted by HeadphoneAddict View Post
I am not doing a full blown review of the Cavalli CTH (compact tube hybrid) - but I will post my impressions so far of its sound and a few comparisons.

I have spent a couple of days with the CTH/Mullard short-plate and find it to be a nice detailed and warm powerful tube hybrid, with above average soundstage and no glaring negatives or complaints in the sound. My main complaints are the lack of a power switch, no RCA input on the rear, and less transportability due to the protruding 12AU7 through the top cover.

I spent some time comparing it vs my Head-direct EF1/stock RCA clear-top 12AU7. One observation was with Giovanni Mirabassi "Prima O Poi" the song Symphomaniax - With HD600 the CTH presented more body to the trumpet, the piano was smoother/refined and more up front, and the sound was mellower overall and slightly darker. But, the sound was also fuller and more refined like you would expect from a bigger amp. In general listening to the CTH was more engaging than the EF1 with stock tube, which seemed a little more distant and presented a slightly less solid image of the instruments.

Switching the EF1 RCA clear top to a Mullard long-plate in the EF1 resulted in the two amps coming much closer together. The EF1 picked up more body and refinement, and became more engaging as well. With the Mullard in the EF1 the treble did become a little more recessed than with the RCA, but not lacking. At this point I cannot pick one amp over the other as the two sound very similar. The volume control on the CTH is much better than the EF1, and I am now convinced that I need to send the EF1 back to have the volume control looked at.

I also compared the CTH to the ALO/RWA Amphora which seems to have a little bit more transparency and detail and yet still has a fairly rich tube-like sound similar to the Cavalli. Yes, sound signatures are somewhat similar but they are not exact. I have not been able to assess soundstage or bass/treble extension yet, but I can say the Cavalli has a little too much bass with the Sennheiser IE8 which sound better on the Amphora. I still don't think I would change anything about the Amphora or CTH with most headphones. With the Grado RS-1 the CTH, EF1 and Amphora also seem to come closer to each other in sound. (can't use the IE8 on the EF1 due to the volume control).

Most of the listening has been with my iMod and portable Vcap dock as source (using Soloz 12-strand Litz-braid mini-RCA or my ALO SXC mini-RCA). The RSA P-51 Mustang was velcro'd to my portable Vcap dock, so I tried it out in comparison too. The P-51 has slightly more treble presence than the CTH or EF1 with Mullards or the Amphora, so it's not quite as mellow as them, but that is about the biggest difference. The other thing you notice is the P-51 is a little more forward and energetic or aggressive sounding, but not in a bad way. The CTH, EF1 and ALO Amphora are a little less aggressive and more refined sounding than the P-51, but the P-51 holds up well against them.

The CTH is a good sounding amp and well worth the money and time to build one, and that is all that matters. I (and others) hate ratings, so I am going to nip the requests for one in the bud. Don't ask me. As you can see from my comparisons, it competes well vs other amps costing more, and as an added bonus it can be used with IEM while my son's Millett SSH and my EF1 cannot, due to poor volume controls. (Millett SSH not compared directly this time around)
Hey Larry, find a Siemens E82CC or 5814A double or triple mica, you will hear details you didnt know was in your music. The German Siemens tube is that good. It wont have the coloring of the long plate mullard, its linear like a 7316 but the sound stage is huge and it is not just ahead of the others in detail, its waaaay ahead of the others for detail retrieval. More detail than your Cleartop and smoother at the same time. I have one now and I just bought 2 from cryoset. eBay has some but they wont be the ruggedized 5814A version. Only one I see on eBay has the triple mica's.

http://www.cryoset.com/catalog/produ...57b38e15e647ae
post #814 of 2204
Quote:
Originally Posted by olblueyez View Post
Hey Larry, find a Siemens E82CC or 5814A double or triple mica, you will hear details you didnt know was in your music. The German Siemens tube is that good. It wont have the coloring of the long plate mullard, its linear like a 7316 but the sound stage is huge and it is not just ahead of the others in detail, its waaaay ahead of the others for detail retrieval. More detail than your Cleartop and smoother at the same time. I have one now and I just bought 2 from cryoset. eBay has some but they wont be the ruggedized 5814A version. Only one I see on eBay has the triple mica's.

Cryoset Online Store
How about you sell me one of yours? For less...

Actually, I am not sure I want to invest that much into the EF1, and I have to return the CTH when I am done.
post #815 of 2204
Quote:
Originally Posted by HeadphoneAddict View Post
How about you sell me one of yours?
The Siemens tubes have become my favorite and I will be selling off a lot of my tubes in the near future. But Siemens wont be one of them. Its hard to get a nice bassy tube with dark headphones like the 650 and most of them make for a combo that is too slow. The Siemens really opens them up. Especially if your dumb enough to have a stock cable on your Senn's. Come on Larry, get your credit card out and go to cryoset, you know you want one.
post #816 of 2204
Quote:
Originally Posted by olblueyez View Post
The Siemens tubes have become my favorite and I will be selling off a lot of my tubes in the near future. But Siemens wont be one of them. Its hard to get a nice bassy tube with dark headphones like the 650 and most of them make for a combo that is too slow. The Siemens really opens them up. Especially if your dumb enough to have a stock cable on your Senn's. Come on Larry, get your credit card out and go to cryoset, you know you want one.
I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb....
post #817 of 2204
Oh, forgot one thing, got some RCA 5814A's in the mail today, another amazing tube. Also linear but more closed in that the Siemens but this sucker has lots of weight across the board. Very nice compliment to the Siemens when you want a change. They go cheap on eBay and would pair especially well with brighter headphones, not that they dont go well with the 650, Im listening to one now and its sweet. It doesn't have any weird coloring, just even and heavy and smooth. I am convinced RCA was the only US tube maker worth a damn. If its not RCA or European then I have no interest.

EDIT: The Gold Brand Sylvanias would be the exception to this rule, very nice tubes. Reminds me, the 5814 Sylvania GB is sweet as hell and its got a nice hump in the bass. Be a good tube for the 701.
post #818 of 2204
Quote:
Originally Posted by HeadphoneAddict View Post
I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb, I will not succumb....
You know how all the tube sellers have "This is the best 12AU7 ever made"? The Siemens really was the best. I have not tried the mucho bucko Tele's, I wont spend that much but aside from that I have tried them all (for the most part) and the Siemens kills them all.
post #819 of 2204
Quote:
Originally Posted by olblueyez View Post
You know how all the tube sellers have "This is the best 12AU7 ever made"? The Siemens really was the best. I have not tried the mucho bucko Tele's, I wont spend that much but aside from that I have tried them all (for the most part) and the Siemens kills them all.
dammittohell...
post #820 of 2204
Quote:
Originally Posted by HeadphoneAddict View Post
dammittohell...
After you hear the Siemens you will feel like taking the RCA cleartop and putting it under your wheels and rolling over it. That will be the first tube to go when I put some tubes up for sale.
post #821 of 2204
Quote:
Originally Posted by olblueyez View Post
After you hear the Siemens you will feel like taking the RCA cleartop and putting it under your wheels and rolling over it. That will be the first tube to go when I put some tubes up for sale.
Well, the RCA cleartop was already relegated to the drawer by the Mullard Long-Plate. I'll let you know what I think about the Siemens next week, don't rub it in, or else...
post #822 of 2204
Quote:
Originally Posted by HeadphoneAddict View Post
Well, the RCA cleartop was already relegated to the drawer by the Mullard Long-Plate. I'll let you know what I think about the Siemens next week, don't rub it in, or else...
The mullard is a good tube but it was too warm and slow for my 650's, especially if your going to upsample your music. The Siemens really was a breath of fresh air.
post #823 of 2204
Quote:
Originally Posted by olblueyez View Post
The mullard is a good tube but it was too warm and slow for my 650's, especially if your going to upsample your music. The Siemens really was a breath of fresh air.
Well, like I said, the Mullard is a little darker than the RCA, or the P-51 and Amphora. But slow it wasn't, despite it's thickness.
post #824 of 2204
I just want ot add that the Sylvania GB 5963 blows the RCA 5814 away. Smoother, more bass weight and more open in the highs. I dont want anyone going lookin for the RCA when you could look for the GB.
post #825 of 2204
12AU7 and 12AU7 Variant Tube Sale!!!

http://www.head-fi.org/forums/f44/tu...8/#post5614946
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